Patent Publication Number: US-10309114-B1

Title: Hand held building tools

Description:
This patent application claims priority to, and is a divisional of U.S. patent application Ser. No. 13/220,606, filed on Aug. 29, 2011, now U.S. Pat. No. 9,051,744, which is a continuation-in-part of U.S. patent application Ser. No. 12/837,707, filed on Jul. 16, 2010, now U.S. Pat. No. 8,286,297, which is a continuation of U.S. patent application Ser. No. 11/371,388, filed on Mar. 9, 2006, now U.S. Pat. No. 7,784,143, which claims benefit of U.S. Provisional Patent Application No. 60/660,460, filed Mar. 11, 2005. These prior patent applications are hereby incorporated herein by reference for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The present invention pertains to methods and various apparatus for building tools. For example, the invention involves methods and various apparatus for high quality durable building tools. 
     BACKGROUND 
     Various building tools have been known in the past for applying, molding, smoothing, and/or texturing material of a working surface with, for example, cement, adhesive, etc. to build, for example, a building. One particular type of building tool for applying, molding, smoothing and/or texturing materials is known as the trowel. Some types of trowels include, for example, a finishing trowel, a swimming pool trowel, and notched trowels of various kinds. These trowels are typically comprised of a blade that contacts the working surface and a handle attached to the blade for a person to grab and move the blade around on a working surface. The trowel blades have various different shapes that are designed for various applications (type of work). During use, the trowel may be used or moved at an angle relative to the working surface so that the outer edges of the trowel experiences friction and wear, such that the trowel edge may become worn out and no longer retain its original shape. Further, if the trowel is dropped the outer edges of the trowel blade may be bent so that in use the trowel does not make the desired working surface shape or result. Therefore, trowel blade durability is an important characteristic for determining the useful life of a trowel, and the durability of the outer edges of the trowel is particularly important. 
     SUMMARY 
     The present invention is directed generally to building tools that are high quality, durable, and strong. For example, various tools that have blades made of a material such as metal that wear through use may have the blades, or portions thereof, that are manufactured to be more durable and have a longer lasting useful life. For example, portions of the blades may be heat treated and cooled so as to harden or strengthen them for improved quality, durability, and strength performance. The invention is particularly useful for building more durable tools that have thin or flat blades. Such tools may include, for example, tools for the building trades including trowels, knives, and scrapers. In one embodiment, a texturing trowel may have one or more portions of its blade heat treated to improve the quality, durability, and strength performance. In one variation, the texturing trowel may have at least a first texturing edge or side of trowel blade heat treated to reduce blade wear or damage so that the quality, durability, and strength of the texturing edge is increased. In another variation, the texturing trowel may have at least a first texturing edge and a second texturing edge that are heat treated for reduced blade wear or damage, the first texturing edge and second texturing edge may be locate on opposite sides of the blade. The texturing edge may be in the shape of, for example, a square notch (or square tooth), a V notch (or triangle tooth), a rounded tooth with a semi-circle or square notch (semi-circle tooth), etc. In one variation, the blade may have various texturing edges of different shapes so that one texturing edge is a different shape than another texturing edge. In another variation, the entire blade may be heat treated and cooled. 
     In another embodiment, the tool may be, for example, a finishing trowel having one or more portions of the blade heat treated and cooled to harden or strengthen it. For example, the working edges of the finishing trowel blade may be flat, smooth and/or non-texturing edges that are heat treated and cooled to harden or strengthen the edge(s) so as to reduce blade wear or damage so that the quality, durability, and strength of the working edge is increased. In a still further embodiment, the tool may be, for example, a swimming pool trowel having one or more portions of the blade heat treated and cooled to harden or strengthen the blade where desired. For example, the working edges, that may include rounded ends of the trowel blade, may be heat treated and cooled to harden or strengthen the edge(s) so as to reduce blade wear or damage so that the quality, durability, and strength of the working edge is increased. In variations, the working edges of the swimming pool trowel may include texturing, may be rounded, and may be heat treated and cooled. Of course, the heating and cooling process of the present invention for hardening or strengthening blades may also be applied to other tools, for example, putty knifes, paint scrapers, notched margin trowels (V and/or square notches), notched taping knifes, brick trowels, pointing trowels, margin trowels, etc., which are made of a non-disposable blade construction preferably having the blade and working edge of the blade securely mounted to or integrally formed with a handle or a handle connecting mechanism. As such, these tools will last longer and will not need to be thrown away or have the blades reworked by, for example, sharpening (not replacing the blade) as often. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The objects, features and advantages of the present invention will become more readily apparent to those skilled in the art upon reading the following detailed description, in conjunction with the appended drawings, in which: 
         FIG. 1  illustrates a perspective view of a first texturing trowel, according to at least one embodiment of the invention; 
         FIG. 2  illustrates a top view of the blade of the texturing trowel shown in  FIG. 1 , according to at least one embodiment of the invention; 
         FIG. 3  illustrates a side view of the blade and handle of the texturing trowel shown in  FIG. 1  prior to assembly together, according to at least one embodiment of the invention; 
         FIG. 4  is a flow chart of a process for making a heated treated tool, according to at least one embodiment of the invention; 
         FIG. 5  illustrates a perspective view of a second texturing trowel, according to at least one embodiment of the invention; 
         FIG. 6  illustrates a top view of the blade of the texturing trowel shown in  FIG. 1 , according to at least one embodiment of the invention; 
         FIG. 7  illustrates a side view of the blade and a handle for a third type of trowel, according to at least one embodiment of the invention; 
         FIG. 8  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 9  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 10  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 11  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 12  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 13  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 14  illustrates the blade of another tool, according to at least one embodiments of the invention; 
         FIG. 15  illustrates another type of building tool, according to at least one embodiment of the invention; 
         FIGS. 16A-16G  illustrate another type of building tool, according to at least one embodiment of the invention; 
         FIG. 17  illustrates another type of building tool, according to at least one embodiment of the invention; 
         FIG. 18  illustrates another type of building tool, according to at least one embodiment of the invention; 
         FIGS. 19A and 19B  illustrate another type of building tool, according to at least one embodiment of the invention; 
         FIGS. 20A and 20B  illustrate another type of building tool, according to at least one embodiment of the invention; 
         FIGS. 21A and 21B  illustrate another type of building tool, according to at least one embodiment of the invention; 
         FIG. 22  illustrates another type of building tool, according to at least one embodiment of the invention; 
         FIG. 23  illustrates another type of building tool, according to at least one embodiment of the invention; 
         FIGS. 24A and 24B  illustrate another type of building tool, according to at least one embodiment of the invention; and 
         FIGS. 25A and 25B  illustrate another type of building tool, according to at least one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention is directed generally to tools that are high quality, stronger, and more durable. As such, the present invention includes various embodiments showing methods and apparatus for building tools that may be, at least in part, made of a material that is heat treated and cooled so as to make its working surface more durable and longer lasting. For example, various tools that have blades made of a material such as metal that wear through use may have the blades, or portions thereof, that are heat treated and cooled so as to harden or strengthen them for improved quality, durability, and strength performance. The invention is particularly useful for building tools with thin or flat blades with edges that will wear through use. The invention is also particularly beneficial to building tools having a texturing surface that is more likely to wear out and lose its original shape. As one skilled in the art will appreciate, the building tools described herein are formed of structures and with designs that are intended to have permanent non-disposable blades which is securely fastened to a handle and/or a handle connection means such that a user would rather throw the worn out tool in the trash when the blade is damaged or worn out to the point where it can not achieve its intended use, and get a completely new tool including a new handle, blade, and handle-to-blade connection mechanism. As such, the present invention of heat treating the blade of these building construction tools allows the blade to last 3-4 times longer without adding the complexity and/or risk of failure in use of a disposable blade mechanization system. 
     Referring to  FIGS. 1-3 , a texturing trowel  100  according to one embodiment of the invention is presented. The texturing trowel  100  may be a V notch trowel used to apply, for example, a cement or adhesive, to a building surface. The V notch trowel may include a blade  105  that may be made of a metal, for example, high carbon steel or other material suitable for acting as a blade  105  of the V notch trowel. The high carbon steel may be of a type ranging between, for example, AISI 1060 high carbon steel and AISI 1095 high carbon steel, which may be a rolled steel sheet that may be cut, punched, or machined to the size of the blade  105 . The AISI 1060 Steel may be an alloy including by weight percentage; C of 0.55-0.66, Fe of 98.35-98.85, Mn of 0.6-0.9, P of a maximum 0.04, and S of a maximum 0.05. The AISI 1095 steel may be an alloy including by weight percentage; C of 0.9-1.03, Fe of 98.35-98.8, Mn of 0.3-0.5, P of a maximum 0.04, and S of a maximum 0.05. The blade  105  may be relatively thin, having a thickness  140  that may be, for example, in the range of 1/16 to 1/64 an inch. The V notch trowel  100  may have a tang  110  made of a metal, for example aluminum, that is coupled to the blade  105  by, for example, welding, brazing, etc. A handle  115  made of, for example, wood, plastic, and/or rubber, may be couple to the tang using, for example a threaded nut  145 , bolt, etc. In this case, the trowel is a V notch trowel  100  and thus may have teeth, for example, teeth  120 , along one or more of its blade edges. In this case, the V notch trowel blade has teeth  120  along three of its four sides. There may be many different notch sizes that may result in many different total numbers of teeth on one or more sides of the trowel. 
     In use, the V notch trowel  100  may be placed at an angle, for example, a 45 degree angle relative to the working surface so that the teeth  120  may contact the working surface only at their points or apex. Used in this manner for spreading, for example, cement or adhesive, the working surface and the cement or adhesive have a textured material shaped in the shape of the V notch or grooves of the trowel. However, due to the friction of the teeth on the working surface or materials being spread on the working surface, the teeth, especially the points of the teeth may be worn down over time resulting in a thinner texturing than desired. As a result, the trowel  100  would need to be reworked or replaced by a new trowel. From this embodiment and this statement of the need to rework or replace the trowel more without using the present invention, one skilled in the art will clearly appreciate that the invention is particularly applicable to buildings tools that are designed and constructed to have a permanent blade, not designed or intended to use replaceable or disposable blades, so that when the blade wears out or looses its intended shape or performance for its intended purpose the entire tool (not just the blade) would need to be thrown away and a new one purchased, or the blade would have to be reworked through manual labor to conform with its original shape or sharpness to work properly for its intended purpose. So, to overcome this problem according to the present invention, at least a portion of the outer edges of the V notch trowel blade, e.g. the outer portion  130  including the teeth  120  may be heat treated and cooled so as to produce a hardened portion of the blade that is more resistant to wear during extensive use. Although the entire blade  105  may be heat treated and cooled to increase the hardness, strength and durability of the outer portion of the teeth  120 , testing has shown that in some cases heat treating the entire blade may result in a blade that is too brittle and breaks more easily if dropped, during the assembly process, for example, when attaching the tang  110  or handle  115  to the blade  105 , or under the pressure applied during repeated use. However, proper selection of the material used to make the blade  105  and the method used in heat treating the blade  105  may help to reduce or solve this problem. In any case, the teeth  120  are harder, stronger and more durable and may last longer within the desired height tolerance, for example up to 3 to 5 times longer. This approach is used in to solve the problems encounter in the art, in contravention to a disposable blade approach that may be used for some other devices where the blade wears out quickly and is far less expensive or integral to the device (e.g., disposable razor blades). Therefore, one skilled in the art will appreciate that the present invention and building construction tools, including the present embodiment related to a notched trowel, are according to the present invention made of a non-disposable blade construction preferably having the blade securely mounted to a handle or a handle connecting mechanism, such as a trowel tang, and these tools will last longer and will not need to be thrown away or have the blades reworked by, for example, manual or machine sharpening (not replacing the blade) as often. 
     In this embodiment, the heat treatment may be performed on, for example, the two longest sides so as to heat treat and harden only the two primary working edges of the trowel  100 . As shown more clearly in  FIG. 2 , the heat treatment may be performed on narrow areas, for example, areas  130   a  and  130   c  (width distance from the tip of the tooth  120  to the solid line) running along the length of the trowel blade  105 . Selecting to heat treat only two edge areas  130   a  and  130   c  may help to protect the most often used edges of the trowel and minimize the setup time and complexity for heat treating the desired portions of the trowel. Although in this case the distance  130   a  and  130   c  is shown to be greater than the height of the teeth  120 , the distance  130   a  and  130   c  may be less than the height of the teeth  120  as will be illustrated more clearly in a later described embodiment. The distances from the tip of the teeth  120  to the dotted lines  125   a  and  125   c  indicate areas where the trowel blade  105  may be cleaned prior to the heat treating process as described in more detail below. In one variation, the front edge (the b side) and/or the back flat edge (the d side) of the blade  105  may be cleaned (e.g., area  125   b ) and the heat treated  130   b  (not shown). 
     Referring to  FIG. 4 , a flow chart of a process for making a heated treated tool according to at least one embodiment of the invention is provided. First, at  405  a blade with or without notches or teeth is formed from a sheet of material, for example, a metal sheet. As mentioned above, the metal may be a high carbon steel such as AISI 1060 steel or AISI 1095 steel to name a few. The shape of the blade may be formed by, for example, stamping, cutting, forming, grinding, etc. Next, at  410 , at least an outer portion of the blade may be cleaned with a degreasing cleanser. The degreasing cleanser may be an alcohol base cleanser that removes dirt and grease to improve the possibility that the heat treating process may be capable of achieving a consistently higher hardness and strength of the material. Although the entire blade  105  may be cleaner at this step, for greater efficiency and lower cost, the area cleaned may be, for example, up to ½ an inch further into the blade than the area to be heat treated, e.g., the distance  125  to be degreased may be greater than the distance  130  to be heat treated. In any case, at least the area to be heat treated should be cleaned, i.e., at least a portion of the outer edge or working edge of the trowel. Next, at  415 , the blade  105  may be placed in a blade transporting and/or blade holding equipment and secured in an orientation desired for heating the targeted portion of the blade  105 . For example, the blade  105  may be held with a pneumatic clamp or other clamping device that allows the area  130   a  and  130   c  to be heat treated to remain exposed and may shield the rest of the blade  105  from the heat treatment. The blade  105  may be held in, for example, a parallel orientation to the heat treatment equipment that is located along either side (a and c) of the blade  105  so that both sides of the blade  105  may be treated simultaneously. 
     Next, at  420 , at least a portion of the blade  105 , for example, areas  130   a  and  130   b , are heated to a desired temperature to harden and strengthen the edge portions and/or teeth  120 . The heat treatment equipment may be, for example, an electric induction heating machine, a furnace, etc, that can heat at least a portion of the blade  105  up to the desired temperature. In the case of an electric induction heating hardening is done by heating the metal with a high frequency alternating magnetic field. Heat is generated by high frequency eddy currents and hysteresis currents on the outer surfaces to be hardened. The primary current may be carried by a water cooled copper electrode. The part to be hardened typically serves as the second electrode in the circuit. Induction heat treating is very fast. Induction hardening of trowel teeth may be accomplished by having the blade  105  stationary and activating the heat treatment equipment for a short period of time or by moving the blade  105  at the appropriate speed on, for example, a conveyor belt through the location where the heat treatment equipment is located. It is understood that those skilled in the art of induction heat treating will know that the range of operating frequency, heating temperature achieved, exposure time at temperature, and cooling rate will vary based on the type of material used to make the blade  105  (e.g., high carbon steel ranging from 1060-1095 steel), the original hardness of the material, the desired final hardness, and the specific geometry for the portions of the blade  105  that are being heat treated, e.g., the edges of the blade. Then at  425 , the blade  105  may be cooled to, for example, room temperature and/or ambient temperature rapidly as through, for example, water cooling. Room temperature may vary in a range of, for example, approximately 5 degrees C. to 36 C, depending on the season and/or conditions in the heat treating facility. Alternatively, the blade could be cooled to ambient or room temperature in a controlled temperature chamber to achieve different hardness and/or strength. Further, the blade may be exposed to a second heating and cooling cycle to temper the heat treated portion of the blade. Then at  430 , a confirmatory test may be performed on the edge or teeth to ensure that the proper hardness has been achieved by the heat treatment. For example, the target hardness may be in a range of approximately 57 to 61 HRC when using, for example, a heat treated blade  105  made of high carbon steel 1095. An untreated blade  105  made of high carbon steel 1095 may have a hardness target or, for example, 44-47 HRC. Other materials may result in different pre and post heat treating target hardness. The result is a blade that is harder, stronger and more durable, having a longer expected life. 
     After testing, as illustrated in  FIG. 3 , the tang  110  and handle  115  may be attached to the blade  105  by, for example, welding, brazing, screws, or any other attachment means that is available. Of course, the heat treating may be performed with the tang  110  and handle  115  already attached to the blade  105 . Although, this may complicate the manufacturing process or adversely affect the coupling between the blade  105  and tang  110 . In general, it is simpler and easier to heat treat the blade  105  prior to assembly with the tang  110  and handle  115 . This process may be applicable regardless of the type or style of blade  105  that is used. Although the process has been described as being applied to an example where two edges of the blade  105  are heat treated, one, two, three, four, or any number of edges, portions or the entire blade  105  may be heat treated to increase its hardness, strength and durability of the desired areas. 
     Referring to  FIGS. 5 and 6 , a perspective view and a top view (without the tang and handle) of a second texturing trowel  500  is provided. The second texturing trowel  500  may have a trowel blade  505  made of a material, for example, a metal. The metal may be, for example, a high carbon steel ranging between AISI 1060 steel and AISI 1095 steel to name a few. In this example, the texturing edge may be in the shape of, for example, a square notch or square teeth  520 . Further, the square notch or teeth  520  may be partially heat treated as shown by distance  530   a , or completely heat treated similar to the embodiments shown in  FIGS. 1-3 . In this case, the heat treatment  530   a  is shown along only one side or edge of the trowel blade  505 , side a. However, it is understood that the heat treatment may be applied to any and all areas of the trowel blade  505 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  505  material so that it is more durable, strong, and long lasting. As such, the blade  505  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  525   a  and/or  525   b , etc., prior to being heat treated. 
       FIG. 7  illustrates a side view of the blade  705  and a handle  715  for a third trowel, according to at least one embodiment of the invention. In this embodiment, the handle  715  is of a different design having two separate attachment points  750  and  760 . The handle  715  may be made of, for example, wood, metal, plastic, rubber, etc. and may be attached to the blade  705  using, for example, screws, molding, adhesive, welding, brazing, etc. The blade  705  may be made of the materials described herein, may have the shape and design as described elsewhere herein, and may be heat treated according to the methods described elsewhere herein. 
     Referring to  FIG. 8 , a top view (without the handle and/or tang) of another texturing trowel blade  805  is provided. This texturing trowel blade may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  805  made of a material, for example, a metal. The metal may be, for example, a high carbon steel ranging between AISI 1060 steel and AISI 1095 steel. In this example, all four texturing edges, a, b, c, and d, may be in the shape of, for example, a V notch or teeth  820 . Further, the V notch or teeth  820  may be partially heat treated as shown by, for example, distance  830   a , a distance more or less than distance  830   a , or completely heat treated, similar to the embodiments shown and described above. In this case, the heat treatment  830   a ,  830   b ,  830   c  and  830   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  805 , side a. However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  805 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  805  material so that it is more durable, strong, and long lasting. As such, the blade  805  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  825   a ,  825   b ,  825   c  and/or  825   d , etc., prior to being heat treated. 
     Referring to  FIG. 9 , a top view (without the handle and/or tang) of another texturing trowel blade  905  is provided. This texturing trowel blade may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  905  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, all four texturing edges, a, b, c, and d, may be in the shape of, for example, a square notch or teeth  920 . Of course a rectangular shape may also be used. Further, the square notch or teeth  920  may be partially heat treated as shown by, for example, distance  930   a , a distance more or less than distance  930   a , or completely heat treated, similar to the embodiments shown and described above. In this case, the heat treatment  930   a ,  930   b ,  930   c  and  930   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  905 . However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  905 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  905  material so that it is more durable, strong, and long lasting. As such, the blade  905  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  925   a ,  925   b ,  925   c  and/or  925   d , etc., prior to being heat treated. 
     Referring to  FIG. 10 , a top view (without the handle and/or tang) of another texturing trowel blade  1005  is provided. This texturing trowel blade may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  1005  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, all four texturing edges, a, b, c, and d, may be in the shape of, for example, a square notch or teeth  1020   a  and  1020   b  and a V notch or teeth  1020   c  and  1020   d . Of course a rectangular shape may also be used. Further, the square notch or teeth  1020   a  and  1020   b  and/or the V notch or teeth  1020   c  and  1020   d , may be partially heat treated as shown by, for example, distance s 1030   a ,  1030   b ,  1030   c , or  1030   d , or a distance more or less than distance any of these distances, or completely heat treated, similar to the various embodiments shown and described above. In this case, the heat treatment area(s)  1030   a ,  1030   b ,  1030   c  and  1030   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  1005 , side a. However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  1005 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1005  material so that it is more durable, strong, and long lasting. As such, the blade  1005  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  1025   a ,  1025   b ,  1025   c  and/or  1025   d , etc., prior to being heat treated. 
     Referring to  FIG. 11 , a top view (without the handle and/or tang) of another trowel blade  1105  is provided. This trowel blade  1105  is for a straight edge trowel and that does not typically texture a working surface. Rather, it is meant for smoothing surfaces. However, its straight edges may be heat treated to make them last longer with extensive use on, for example, abrasive work surfaces, and be more durable if dropped so that the straight edge remains straight longer. In any case, the blade  1105  may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  1105  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, all four of the edges, a, b, c, and d, may be straight and a portion thereof heat treated, as shown by solid lines with a distance of  1130   a ,  1130   b ,  1130   c , and/or  1130   d . One or more of these edges may be partially heat treated as shown by, for example, distance  1130   a , a distance more or less than distance  1130   a , or completely heat treated, similar to the embodiments shown and described above. In this case, the heat treatment area(s)  1130   a ,  1130   b ,  1130   c  and  1130   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  1105 . However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  1105 , as desired. The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1105  material so that it is more durable, strong, and long lasting. As such, the blade  1105  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  1125   a ,  1125   b ,  1125   c  and/or  1125   d , etc., prior to being heat treated. 
     Referring to  FIG. 12 , a top view (without the handle and/or tang) of another texturing trowel blade  905  is provided. This texturing trowel blade may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  1205  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, all four texturing edges, a, b, c, and d, may be in the shape of, for example, a square notch and rounded teeth  1220 . Of course a rounded shape notch may also be used. Further, the square notch and rounded teeth  1220  may be partially heat treated as shown by, for example, distance  1230   a , a distance more or less than distance  1230   a , or completely heat treated, similar to the embodiments shown and described above. In this case, the heat treatment  1230   a ,  1230   b ,  1230   c  and  1230   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  1205 . However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  1205 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1205  material so that it is more durable, strong, and long lasting. As such, the blade  1205  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  1225   a ,  1225   b ,  1225   c  and/or  1225   d , etc., prior to being heat treated. 
     Referring to  FIG. 13 , a top view (without the handle and/or tang) of another trowel blade  1305  is provided. This trowel blade  1305  is for a swimming pool trowel having straight edge sides a and c and rounded sides b and d, that does not typically texture a working surface. Rather, it is meant for producing smooth surfaces in, for example, a swimming pool. However, its straight edges (a and c) and rounded edges (b and d) may be heat treated to make them last longer with extensive use on, for example, abrasive work surfaces such as cement, and be more durable if dropped so that the straight edges (a and c) and rounded edges (b and d) remains straight longer. In any case, the blade  1305  may be couple to one of a number of handle designs (not shown attached thereto). The trowel blade  1305  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, all four of the edges, a, b, c, and d, may be straight and a portion thereof heat treated, as shown by solid lines with a distance of  1330   a ,  1330   b ,  1330   c , and/or  1330   d . One or more of these edges may be partially heat treated as shown by, for example, distance  1330   a , a distance more or less than distance  1330   a , or completely heat treated, similar to the embodiments shown and described above. In this case, the heat treatment area(s)  1330   a ,  1330   b ,  1330   c  and  1330   d  are shown along each of the four sides or edges (a, b, c and d) of the trowel blade  1305 . However, it is understood that the heat treatment may be applied to any and all of these or other areas of the trowel blade  1305 , as desired. In this case it may be particularly desirable to hear treat edges b and d since they are rounded. The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1305  material so that it is more durable, strong, and long lasting. As such, the blade  1305  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  1325   a ,  1325   b ,  1325   c  and/or  1325   d , etc., prior to being heat treated. 
     Referring to  FIG. 14 , a top view (without the handle and/or tang) of another trowel blade  1405  is provided. This trowel blade  1405  may be a multi-shaped tooth trowel having straight edge sides a and b and textured sides b and d. The textured sides b and d may have a plurality of different shaped teeth,  1440   c ,  1441   c ,  1442   c ,  1443   c , that may texture a working surface. This texturing trowel  1405  may have a trowel blade  505  made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel to name a few. In this example, the texturing edge may be in the shape of, for example, a repeating pattern of teeth, for example, four different shaped teeth in series that repeat to form a complete side of texturing teeth, for example sides c and d. Of course the repeating pattern may be of 2, 3, 4, etc. number of teeth. Further, the multi-shaped notches or teeth along side c may be partially heat treated or completely heat treated as shown by distance  1430   c . In this case, the heat treatment  1430   c  is shown along only one side or edge of the trowel blade  1405 , side c. However, it is understood that the heat treatment may be applied to any and all areas of the trowel blade  1405 . The heat treatment may be performed using, for example, any of the processes described above, or a similar process, for hardening the blade  1405  material so that it is more durable, strong, and long lasting. As such, the blade  1405  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example areas  1425   a  and/or  1425   c , etc., prior to being heat treated. Although, it would be understood by one skilled in the art that the invention may be applicable to trowels with blades and teeth having any of a number of shapes and combination thereof. Now, various other types of exemplary building tool embodiments of the present invention will be provided. 
     Referring to  FIG. 15 , a side view of another building tool, a putty knife or spackle knife  1500  is provided. This exemplary putty knife  1500  is used in the building and construction trades and may include a blade  1505  that may be permanently attached or coupled to a handle  1510  using, for example, rivets  1515  (with a opening in the center) and  1520 . The interface of the blade  1505  and the handle  1510  occur at line  1530 , and may be where they are in close proximity to each other when viewed from the side, having the hand composed of two separate pieces on either side of the continuation of the blade  1505  extending the entire length of the putty knife  1500 . In such a construction, the rivets  1515  and  1520  may be used to permanently secure the two handle sections (only one shown in this side view) together on either side of the flat elongated blade  1505  material. In one variation, the two handles may be permanently held together and to the blade using a two piece core and an over mold to hold the two pieces together (as shown in the next embodiment). 
     The putty knife handle  1510  may be made of one of numerous materials, for example, wood, cork, plastic, rubber, etc., that may be two hollow or solid pieces, or have a hole through the center to accommodate a means of attaching the handle  1510  to the blade  1505  in a permanent manner (e.g. welding, epoxy adhesive, etc.). The putty knife blade  1505  may be made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, stainless steel, etc., to name a few. In this example, the primary working edge of the blade  1505  may have a portion thereof heat treated, as shown by solid line with a distance of 1525. In variations of this theme, other edges or the entire blade  1505  of the putty knife may also be heat treated if desired. However, heat treating the entire blade  1505  may make the entire length of the flattened blade section more brittle and more subject to cracking or breaking at, for example, the area around the handle-to-blade interface  1530 . As such, it is preferable that at least the working edge may be partially heat treated as shown by, for example, distance  1525 , or a distance more or less than distance  1525 , rather than completely heat treated, similar to the various embodiments shown and described above. In this case, the heat treatment area  1525  is shown only along one of the edges of the putty knife blade  1505 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1505  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  1505  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1527 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the putty knife building construction tool, is made of a non-disposable blade construction preferably having the blade  1505  securely mounted to a handle  1510  and/or a handle connecting mechanism (e.g., rivets  1515  and  1520 , or structure welded to the blade and inserted into the handle) and the putty knife will last longer and will not need to be thrown away or have the heat treated working edge  1525  of the blade  1505  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. Therefore, using the present invention, standard putty knife designs like shown in  FIG. 15 , that typically do not have quick replacement blade designs or constructions, last much longer before the working surface of the blade  1505  needs reworked of the entire putty knife  1500  is thrown away and a new putty knife  1500  is purchased to replace it. 
     Referring to  FIGS. 16A-16G , a more detailed description of a molded over handle putty knife or spackle knife  1600  having a wider blade is provided. In  FIG. 16A , a perspective view of the putty knife or spackle knife  1600  is provided. This exemplary putty knife  1600  is typical of those used in the building and construction trades and may include a blade  1605  that may be permanently attached or coupled to a handle  1610  using, for example, a handle comprised of a two sectioned internal handle structure made of plastic (placed on either side of at least a part of the elongated flat blade structure) and a rubber over mold holding that hold the two sectioned handle structure to each other and the blade  1605 . Alternatively, the handle  1610  could permanently attached to the blade  1605  using two rivets. The interface of the blade  1605  and the handle  1610  occur at area  1624 . In any case, the over molded handle  1610  may be composed of three separate pieces on either side of the continuation of the blade  1605  extending the entire length of the putty knife  1600 , or almost the entire length with an end cap on its far end. In such a construction, the three component handle structure with rubber over mold may be used to permanently secure the two plastic handle sections (together on either side of the flat elongated blade  1605  material. 
     The putty knife blade  1605  may be made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, the primary working edge of the blade  1605  may have a portion thereof heat treated, as shown by solid line with a distance of  1625 . In variations of this theme, other edges or the entire blade  1605  of the putty knife may also be heat treated if desired. However, heat treating the entire blade  1605  may make the entire length of the flattened blade section more brittle and more subject the cracking or breaking at, for example, the area around the handle-to-blade interface  1624  or where a handle-to blade attachment means would be permanently attached to the blade  1605  (one may consider the portion of the flat metal from the blade area  1605  extending into the handle  1610  as being a handle-to-blade attachment mechanism or tang, as it performs the same function even though made integral to the blade in this example). As such, it is preferable that at least the working edge may be partially heat treated as shown by, for example, distance  1625 , or a distance more or less than distance  1625 , rather than completely heat treated, similar to the various embodiments shown and described above. In this case, the heat treatment area  1625  is shown only along one of the edges of the putty knife blade  1605 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1605  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  1605  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1627 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the putty knife or spackle knife building construction tool, is made of a non-disposable permanently attached blade construction preferably having the blade  1605  securely mounted to a handle  1610  and/or a handle connecting mechanism (not shown here) and the putty knife will last longer and will not need to be thrown away or have the heat treated working edge  1625  of the blade  1605  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. Therefore, using the present invention, standard putty knife designs like shown in  FIG. 16A , that typically do not have quick replacement blade designs or constructions, last much longer before the working surface of the blade  1605  needs reworked of the entire putty knife  1600  is thrown away and a new putty knife  1600  is purchased to replace it. It is noteworthy that if the blade  1605  is sufficiently wide, e.g., six inches or more, than this tool may be considered a taping knife rather than a putty knife or spackle knife. 
     Referring to  FIG. 16B , another variation of the invention with a perspective view is provided. In this figure, the putty knife  1600  includes a blade  1605  connected to a handles  1610 . As with  FIG. 16A , the putty knife  1600  handle  1610  may be comprised of three pieces, two opposing plastic pieces (e.g.,  1690 ) that are on either side of the extended blade  1605  or handle-to-blade connection mechanism, and a rubber over mold  1628  that holds the two plastic portions together or simply surrounds them. In one variation the plastic portion may be made formed permanently around the blade  1605  using an injection molding process. Alternatively, the handle  1610  may be a single piece having an elongated hollow hole at it center wherein an extended portion of the blade  1605  is inserted or an injection molded single piece of plastic (e.g.,  1690 ) that covers, surrounds, and holds to the handle  1610  to the extended blade portion. In the former case, an attachment means  1645  may be used to couple the blade  1605  to the handle  1610  and keep the blade  1605  from retracting from the handle  1610 , and/or attaching an end cap  1660 . The attachment means may be formed of, for example, metal or plastic, and may have a hole formed therein, appearing as an oversized and/or elongated rivet. Further, the putty knife  1600  may have an end cap  1660  that is securely coupled to the far end of the handle  1610 . Again, in this embodiment, the primary working edge of the blade  1605  may have a portion thereof heat treated, as shown by solid line with a distance of  1625  and the blade  1605  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1627 , prior to being heat treated. Also, as noted above, the handle may be affixed to the blade in what would be considered by one skilled in the art as permanently, and does not use a disposable or replaceable blade design, but provides longer useful life by heat treatment of the blade, at least in part because the relatively high initial cost of the entire putty knife  1600  and its respective replacement cost. For a relatively small amount of cost related to the heat treatment of at least the working portion of the blade  1605 , the life of the putty knife  1600  can be increased by approximately 3-4 times and the design is not complicate or made unnecessarily heavier by adding a removable blade feature. 
     Referring to  FIG. 16C , another perspective view of the putty knife or spackling knife  1600  is provided showing a better view of the end cap angle. 
     Referring to  FIG. 16D , provides a side plan view of the putty knife  1600 . From this view, one can appreciate the five or six main parts or areas of the putty knife  1600 . The putty knife handle  1610  may be comprised of, for example, four main pieces, a central housing  1690  made of, for example, a molded plastic that surrounds the handle end of the blade  1605  or handle-to-blade connection mechanism (only a small portion of  1690  next to end cap  1660  shows in this view), an over mold section  1630  that may be made of, for example, a plastic or rubber, a rivet  1645  having a hole therein  1650 , and an end cap  1660  that may be made of, for example, a durable plastic or a metal (so that it may be struck by a hammer or such). The blade  1605  once again, in this embodiment, includes the primary working edge of the blade  1605  that has a portion thereof heat treated, as shown by solid line with a distance of  1625  (and the blade  1605  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1627 , prior to being heat treated). 
     Referring to  FIG. 16E , another plan view of the putty knife or spackling knife  1600  is provided showing a side view of the putty knife  1600  from the end cap  1660  side. The putty knife handle  1610  may be comprised of, for example, an inner or central housing  1690  that extends in part to the exterior surface of the handle  1610 , and extends inward to surround the handle end of the blade  1605  or handle-to-blade connection mechanism (again, only a small portion of  1690  next to end cap  1660  shows in this view), an over mold section  1630  (to both the left and right), a rivet  1645  having a hole  1650  therein, and an end cap  1660  that may also have a hone or indent  1626  therein. Finally, the wider portions of the blade extend to the right and left of the handle portions. It is noteworthy from this view one can see that the putty knife is symmetrical about a center axis (see  FIGS. 16B-16D  also). 
     Referring to  FIG. 16F , another plan view of the putty knife or spackling knife  1600  showing a side view of the putty knife  1600  from either the left or right side. It is noteworthy that from this perspective one can see the clearly at the inward side  1624  of the handle  1610  that the inner or central housing portion  1690  is covered by the over mold portion  1628 . Further, the putty knife  1600  from this perspective is also symmetrical about center line XX ( 1632 ). 
     Referring to  FIG. 16G , a cross-section view of the putty knife or spackling knife  1600  is provided as taken along line  1655 A as shown in  FIG. 16D . From this view, one can most clearly see that the elongate blade portion  1605  that extends through the handle portion  1610  is almost entirely covered by the inner or central housing portion  1690 , which is locked therewith by in-part the material of  1690  being channeled through a hole  1695  in the end of the blade  1605  covered by the inner or central housing portion  1690 . The handle may also be secured to the blade  1605  or the handle-to blade connecting mechanism by the rivet  1645  and/or the end cap  1660  may be coupled to the handle  1610  by the rivet  1645  (note portions  1662  and  1656  of the end cap  1600  surrounding the through hole area  1650  of the rivet  1645 ). As can be seen from this view also, the majority of the inner or central housing portion  1690  may be covered by the over mold section  1630  from the blade  1605  connection entry side of the handle  1610  up corner or ridge  1619 . The blade  1605  once again, in this embodiment, includes the primary working edge of the blade  1605  that has a portion thereof heat treated, as shown by solid line with a distance of  1625  (and the blade  1605  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1627 , prior to being heat treated). Once again, the putty knife  1600  from this perspective is also symmetrical about center line XX ( 1632 ). 
     Referring to  FIG. 17 , a perspective view of another building tool, a taping knife or joint knife  1700  is provided. Taping knifes are made with particularly wide (e.g., 6-10 inch or more blades) and flexible blades for applying, for example, plaster or mastic material to tape that is used to cover, for example, joints between drywall boards in interior room wall and ceiling structures. Ideally, the blades of the are made of a flexible metal such as stainless steel or a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. This exemplary taping knife  1700  is used in the building and construction trades and may include a blade  1705  that may be permanently attached or coupled to a handle  1710  using, for example, rivets  1771  and  1777 , or an adhesive, welding, or brazing the respective parts together. The blade  1705  and the handle  1710  may be coupled together with a handle-to-blade mechanism  1715 , that may be made of, for example, a plastic or a metal such as aluminum. The handle-to-blade mechanism  1715  may be attached to the handle via a grove  1769  in a proximal end of the handle  1710 , and the blade  1705  may be couple to the mechanism  1715  via an elongated groove along the mechanism  1715 . The handle  1710  may be made of such materials as wood, cork, plastic, molded rubber over one of these materials, light weight metals such as aluminum or magnesium, etc. The handle  1710  may also have an end cap  1723  that is attached to the distal end  1721  of the handle  1710 . The taping knife handle  1710  may be attached to the blade  1705  in a permanent manner (e.g. welding, epoxy adhesive, etc.). The taping knife blade  1705  may be made of a material, for example, a metal. The metal may be, for example, stainless steel, a high carbon steel such as AISI 1060 steel, or AISI 1095 steel, to name a few. In this example, the primary working edge of the blade  1705  may have a portion thereof heat treated, as shown by solid line with a distance of  1725 . In variations of this theme, other edges or the entire blade  1705  of the taping knife may also be heat treated if desired. However, heat treating the entire blade  1705  may make the entire length of the thin flattened blade section more brittle and more subject the cracking or breaking at, for example, the area around the handle-to-blade  1715  interface with the blade  1705 . As such, it is preferable that at least the working edge may be partially heat treated as shown by, for example, distance  1725 , or a distance more or less than distance  1725 , rather than completely heat treated, similar to the various embodiments shown and described above. In this case, the heat treatment area  1725  is shown only along one of the edges of the taping knife blade  1705 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1705  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  1705  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1727 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the putty knife building construction tool, is made of a non-disposable blade construction preferably having the blade  1705  securely mounted to a handle  1710  and/or a handle connecting mechanism  1717 , e.g., rivets  1771  and  1777 , or structure welded to the blade and inserted into the handle-to-blade connection means  1715 , and the taping knife  1700  will last longer and will not need to be thrown away or have the heat treated working edge  1725  of the blade  1705  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. Therefore, using the present invention, standard taping knife designs like shown in  FIG. 17 , that typically do not have quick replacement blade designs or constructions, last much longer before the working surface of the blade  1705  needs reworked of the entire taping knife  1700  is thrown away and a new taping knife  1700  is purchased to replace it. 
     Referring to  FIG. 18 , a perspective view of another building tool, a taping knife or joint knife  1800  having a slightly different handle-to-blade connection is provided. In this embodiment, the blade  1805  and the handle  1810  may be coupled together with a handle-to-blade mechanism  1824 , that may be made of, for example, a plastic or a metal such as aluminum that is wrapped around the upper edge  1822  of the blade  1805 . The handle-to-blade mechanism  1824  may be attached to the handle via a grove  1840  in a proximal end of the handle  1810 , and the blade  1805  may be couple to the mechanism  1815  via an elongated groove along the mechanism  1824 . The handle  1810  may be made of such materials as wood, cork, plastic, molded rubber over one of these materials, light weight metals such as aluminum or magnesium, etc. The handle  1810  may also have an end cap  1844  that is attached to the distal end  1828  of the handle  1810 . The taping knife handle  1810  may be attached to the blade  1805  in a permanent manner (e.g. welding, epoxy adhesive, etc.). The taping knife blade  1805  may be made of a material, for example, a metal. The metal may be, for example, stainless steel, a high carbon steel such as AISI 1060 steel, or AISI 1095 steel, to name a few. In this example, the primary working edge of the blade  1805  may have a portion thereof heat treated, as shown by solid line with a distance of  1825 . In variations of this theme, other edges or the entire blade  1805  of the taping knife may also be heat treated if desired. However, heat treating the entire blade  1805  may make the entire length of the thin flattened blade section more brittle and more subject the cracking or breaking at, for example, the area around the handle-to-blade  1824  interface with the blade  1805 . As such, it is preferable that at least the working edge may be partially heat treated as shown by, for example, distance  1825 , or a distance more or less than distance  1825 , rather than completely heat treated, similar to the various embodiments shown and described above. In this case, the heat treatment area  1825  is shown only along one of the edges of the taping knife blade  1805 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  1805  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  1805  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  1727 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the taping knife building construction tool, is made of a non-disposable not replaceable blade construction preferably having the blade  1805  securely mounted to a handle  1810  and/or a handle connecting mechanism  1824 , e.g., rivets  1826 , or structure welded to the blade and inserted into the handle-to-blade connection means  1826 , and the taping knife  1800  will last longer and will not need to be thrown away or have the heat treated working edge  1825  of the blade  1805  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. In one variation, the handle  1810  may be permanently connected to the handle connection mechanism  1824  by molded over plastic and pins there through. 
     Referring to  FIGS. 19A and 19B , a perspective view and plan view, respectively, of a brick trowel or pointing trowel  1900  is provided. One skilled in the art would recognize that the structure of the brick trowel or pointing trowel  1900  may be essentially the same as the finishing trowel described above and may be constructed using the same materials and/or methods. However, the brick trowel or pointing trowel  1900  has a pointed blade  1905 . As such, the brick trowel or pointing trowel  1900  includes a handle  1910 , a handle-to-blade connection means or a tang  1920 , and a blade  1905  permanently attached together. The blade  1905  may be, for example, formed integrally with or welded to the tang  1920  at connection  1930 , and may be made of a metal such as those mentioned above. The handle may be made of, for example, wood, plastic, rubber molded over plastic, etc. The tang  1920  may be inserted into at least a portion of the handle  1910  through an opening  1935  in one end of the handle  1910 . The blade  1905  may be heat treated along one, two or more of its working surfaces as shown along the perimeter of the blade at a distance from the outside working edge inward shown as solid line  1925  to make the working edges more durable and longer lasting. However, because the working edges of a brick trowel or pointing trowel blade  1905  may have a slight bow or convex shape to them, that distance may vary along the lateral length as show by distance  1926  being less than distance  1925  from the working edge. A cleaning may be performed at a distance  1927  from the working edge as shown by the dotted lines.  FIG. 19B  shows an embodiment in which the handle  1910  may have and end cap(s)  1940  and/ 1945 , along with a heat treatment that has the same curvature or convex shape of the pointed blade  1905 . 
     Referring to  FIGS. 20A and 20B  illustrate a perspective view and a plan view, respectively, of another type of building tool, a corner trowel or corner finishing knife, according to at least one embodiment of the invention. One skilled in the art will recognize that the structure of the corner trowel or corner finishing knife  2000  is similar to the various trowels above in that there is a handle  2010 , a blade  2005 , and a handle-to-blade connection mechanism or tang  2020 , that may be constructed using the same materials and/or methods as described above. However, the corner trowel or corner finishing knife  2000  has a bent or angled blade  2005  that may, for example, have and angle between the two sides of approximately 90 degrees. The corner trowel or corner finishing knife  2000  may also have a means for holding the angled blade  2005  to its intended angle and reinforcing the attachment of the blade  2005  to the tang  2020 , an angle assurance and reinforcement mechanism  2030 , that may be securely attached to the blade  2005  and the tang  2020  by, for example, welding, brazing, adhesive, etc. The angle assurance and reinforcement mechanism  2030  may be made out of, for example a metal (such as those mentioned above), a plastic, an epoxy resin, etc. As such, the corner trowel or corner finishing knife  2000  includes a handle  2010 , a handle-to-blade connection means or a tang  2020 , and a blade  2005  permanently attached together. The blade  2005  may be made of, for example, a metal such as those mentioned above. The handle  2010  may be made of, for example, wood, plastic, rubber molded over plastic, etc., and may include an end cap  2040  (or not). The tang  2020  may be inserted into at least a portion of the handle  2010  through an opening  2035  in one end of the handle  2010 . The blade  2005  may be heat treated along one, two, or three of its working surfaces as shown along the perimeter of the blade at a distance from the outside working edge inward shown as solid line  1925  to make the working edges more durable and longer lasting. A cleaning may be performed at a distance  1927  from the working edge as shown by the dotted lines. 
     Referring now to  FIGS. 21A and 21B , these figures illustrate a perspective view and plan view of a notched taping knife  2100 , another type of building tool, according to at least one embodiment of the invention. This exemplary notched taping knife  2100  is typical of those used in the building and construction trades and may include a blade  2105  that is reasonably wide, for example six inches with a bump or concave portion  2007  at the center of the working edge of the blade  2105  and may be permanently attached or coupled to a handle  2110  using, for example, a handle comprised of a two sectioned internal handle structure made of plastic (placed on either side of at least a part of the elongated flat blade structure) and a rubber over mold holding that hold the two sectioned handle structure to each other and the blade  2005 . In this example, the internal sections  2135  and  2140  of the handle  2110  illustrate either internal handle material that is thick enough to be exposed as an outside surface, and/or a contour portion of the handle  2110 . The construction may be the same as or similar to that of the handle shown above in  FIGS. 16A-G  above. Alternatively, the handle  2110  could permanently attached to the blade  2105  using two rivets (not shown in this embodiment). The interface of the blade  2105  and the handle  2110  occur at area  2130 . The handle may also include a hole  2115  there through at the distal end of the handle (away from the working end of blade  2105 ). In such a construction, handle structure with rubber over mold may be used to permanently secure the two plastic handle sections (together on either side of the flat elongated blade  2105  material or handle-to-blade connection mechanism). The notched taping knife  2100  blade  2105  may be made of a material, for example, a metal. The metal may be, for example, a stainless steel, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, to name a few. In this example, the primary working edge of the blade  2105  may have a portion thereof heat treated, as shown by solid line with a distance of  2125 . In variations of this theme, other edges or the entire blade  2105  of the notched taping knife  2100  may also be heat treated if desired. However, heat treating the entire blade  2105  may make the entire length of the flattened blade section and integral elongate handle connection mechanism more brittle and more subject to cracking or breaking at, for example, the area around the handle-to-blade interface  2130  or where a handle-to blade attachment means would be permanently attached to the blade  2130  (again, one may consider the portion of the flat metal from the blade area  2105  extending into the handle  2110  as being a handle-to-blade attachment mechanism or tang, as it performs the same function even though made integral to the blade in this example). As such, it is preferable that at least the working edge may be partially heat treated as shown by, for example, distance  2125 , or a distance more or less than distance  2125 , rather than completely heat treated, similar to the various embodiments shown and described above. The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  2165  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  2105  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  2127 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the notched taping knife  2100  building construction tool, is made of a non-disposable permanently attached blade construction preferably having the blade  2105  securely mounted to a handle  2110  and/or a handle connecting mechanism (inside the handle  2110 , not shown here) and the notched taping knife  2100  will last longer and will not need to be thrown away or have the working edge area end of the blade  2105  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. Therefore, using the present invention, standard notched taping knife  2100  designs like shown in  FIGS. 21A and 21B , that typically do not have quick replacement blade designs or constructions, last much longer before the working surface of the blade  2105  needs reworked of the entire notched taping knife  2100  is thrown away and a new notched taping knife  2100  is purchased to replace it. As noted above since the blade  2105  is sufficiently wide, e.g., six inches or more, than this tool may be considered a taping knife rather than a putty knife or spackle knife. 
     Referring to  FIG. 22  a perspective view of a margin trowel, another type of building tool, is provided, according to at least one embodiment of the invention. One skilled in the art will recognize that the structure of the margin trowel  2200  is similar to or the same as the various trowels above in that there is a handle  2210 , a blade  2205 , and a handle-to-blade connection mechanism or tang  2220 , that may be constructed using the same materials and/or methods as described above. However, the margin trowel  2200  has a smaller narrower blade  2205  that may allow its blade  2205  to be formed by stamping a rode of metal flat that is also used to make the tang  2220 . As such, the blade  2205  and the tang  2220  may be more easily made as one contiguous integral piece of material, but having different shapes and purposes, so that the tang  2220  does not need to be permanently attached to the blade  2205  by, for example, welding, brazing, etc., at inflection point  2330 . As such, the margin trowel  2200  may include a handle  2210 , a handle-to-blade connection means or a tang  2220 , and a blade  2205 , permanently attached together. The blade  2205  may be made of, for example, a metal such as those mentioned above or others that will meet the characteristics needed for the tool&#39;s intended use(s). The handle  2210  may be made of, for example, wood, plastic, rubber molded over plastic, etc., and may include an end cap  2240  or  2250  (or not). The tang  2220  may be inserted into at least a portion of the handle  2210  through an opening  2235  in one end of the handle  2210 . The blade  2205  may be heat treated along one, two, or three of its working surfaces as shown along the perimeter of the blade at a distance  2225  from the outside working edge inward shown as solid line  2225  to make the working edges more durable and longer lasting. A cleaning may be performed at a distance  2227  from the working edge as shown by the dotted lines. 
     Referring to  FIG. 23  a perspective view of a notched margin trowel  2300 , another type of building tool, is provided, according to at least one embodiment of the invention. One skilled in the art will recognize that the structure of the notched margin trowel  2300  is the same as the margin trowel  2200  above except that one or more of the working edges of the blade  2305  may be notched; two such notched working edges are shown in the exemplary embodiment of  FIG. 23 . As such, the notched margin trowel  2300  has a handle  2310 , a blade  2305 , and a handle-to-blade connection mechanism or tang  2320 , that may be constructed using the same materials and/or methods as described above. As with the margin trowel  2200 , the notched margin trowel  2300  may have a smaller narrower blade  2305  that may allow its blade  2305  to be formed by stamping a rode of metal flat that is also used to make the tang  2320 . As such, the blade  2305  and the tang  2320  may be more easily made as one contiguous integral piece of material, but having different shapes and purposes, so that the tang  2320  does not need to be permanently attached to the blade  2305  by, for example, welding, brazing, etc., at inflection point  2330 . As such, the notched margin trowel  2300  may include a handle  2310 , a handle-to-blade connection means or a tang  2320 , and a blade  2305 , permanently attached together. The blade  2305  may be made of, for example, a metal such as those mentioned above or others that will meet the characteristics needed for the tool&#39;s intended use(s). The handle  2310  may be made of, for example, wood, plastic, rubber molded over plastic, etc., and may or may not include an end cap  2340  or  2345  (or not). The tang  2320  may be inserted into at least a portion of the handle  2310  through an opening  2335  in one end of the handle  2310 . The blade  2305  may be heat treated along one, two, or three of its working surfaces as shown along the perimeter of the blade at a distance  2325  from the outside working edge inward shown as solid line  2325  to make the working edges more durable and longer lasting. A cleaning may be performed at a distance  2327  from the working edge as shown by the dotted lines. 
     Referring to  FIGS. 24A and 24B  a top perspective view and bottom perspective view, respectfully, of a heavy duty paint scraper  2400  are provided to illustrate another type of building tool, according to at least one embodiment of the invention. In this embodiment, one skilled in the art will appreciate that the blade  2405  may be bent and may be made of a very rigid metal material so as to retain that bent structure form while under pressure during extended use (although the previously mentioned metals would work). As such, it is more likely that the entire blade  2405  of this particular design of paint scraper may be heat treated to improve the performance and longevity of not just one or more working edges, but the entire blade. In any case, the paint scraper  2400  may have an elongated handle  2410 , a blade  2405 , and a handle-to-blade connection mechanism or head  2420  to connect the handle to the blade. In a preferred embodiment, the handle  2410  and the handle-to-blade connection mechanism  2420  may be formed of one integrally formed structure by, for example, being made of a molded hard plastic. machined or carved wood, or cast metal such as aluminum or magnesium (lightweight). However, it is sufficient if the handle  2410  and the handle-to-blade connection mechanism or head  2420  are formed separately and then permanently affixed to one another after they are formed. In any case, the blade  2405  may be attached to the handle-to-blade connection mechanism or head  2420  using a permanent connection means, for example, a rivet  2430 . Alternatively, the blade  2405  could be permanently attached to the handle-to-blade connection mechanism or head  2420  by using injection molding to mold at least the handle-to-blade connection mechanism or head  2420  around the large part of the blade  2405  (see bottom view in  FIG. 24B ). The handle may include a hole  2415  there through. The blade  2405  may be heat treated along at least one of its working surfaces or edges as shown along the perimeter of the blade at a distance  2425  from the outside working edge inward shown as solid line  2425  to make at least the working edges more durable and longer lasting. A cleaning may be performed at a distance  2327  from the working edge as shown by the bracket to the side of the blade, i.e., the entire bent down portion of the blade  2405 . Of course, as previously mentioned with respect to other embodiment of the invention, the heavy duty paint scraper  2400  is intended to have a permanently attached blasé  2405  that will last longer by the heat treatment of the blade or a portion thereof so that the entire heavy duty paint scraper  2400  lasts longer and does not need to be replaced as often. 
     Referring to  FIGS. 25A and 25B , perspective views of two other types of paint scrapers  2500  that illustrate another type of building tool are provided, according to at least one embodiment of the invention. One skilled in the art will appreciate that the paint scrapers shown in  FIGS. 25A and 25B  are similar in many respects to the putty knife and spackle knifes shown above in  FIGS. 15-16G , but typically the paint scraper will have at least two distinct differences including a sharp beveled edge  2540  on its primary working edge and a stronger and more firm or rigid base blade material. As such, like the paint scraper  2400  above, these paint scrapers are more likely that the entire blade  2505  of this particular design of paint scraper may be heat treated to improve the rigidity, firmness, performance and longevity of not just one or more working edges, but the entire blade  2505 . This exemplary paint scraper  2500  is used in the building and construction trades and may include a blade  2505  that may be permanently attached or coupled to a handle  2510  using, for example, rivets  2515  (with a opening in the center) and  2520 . The interface of the blade  2505  and the handle  2510  occur at line  2530 , and may be where they are in close proximity to each other when viewed from the side, having the hand composed of two separate pieces on either side of the continuation of the blade  2505  extending the entire length of the paint scraper  2500 . In such a construction, the rivets  2515  and  2520  may be used to permanently secure the two handle sections (only one clearly shown in these perspective views, the bottom half is barely visable) together on either side of the flat elongated blade  2505 A material. In one variation, the two handles may be permanently held together and to the blade using a two piece core and an over mold to hold the two pieces together (as shown in  FIGS. 16A-G ). 
     The paint scraper handle  2510  may be made of one of numerous materials, for example, wood, cork, plastic, rubber, etc., that may be two hollow or solid pieces, or have a hole through the center to accommodate a means of attaching the handle  2510  to the blade  2505  in a permanent manner (e.g. welding, epoxy adhesive, etc.). The paint scraper blade  2505  may be made of a material, for example, a metal. The metal may be, for example, a high carbon steel such as AISI 1060 steel or AISI 1095 steel, stainless steel, etc., to name a few, that has high strength and rigidity (perhaps from heat treating the entire blade). In this example, the primary working edge of the blade  2505  may be beveled  2540  and may have a portion thereof heat treated, as shown by solid line with a distance of  2525 . In variations of this theme, other edges, for example, angled edge  2545  (that may be used for opening or cleaning paint can lids and/or sealing groves) and semicircle  2535 , or the entire blade  2505  of the paint scraper  2500  may also be heat treated if desired. However, as previously noted heat treating the entire blade  2505  may make the entire length of the flattened blade section more brittle and more subject to cracking or breaking at, for example, the area around the handle-to-blade interface  2530 . As such, it may be preferable in some cases that uses a base metal that is already sufficiently sturdy and rigid, that instead one or more of only the working edges may be heat treated as shown by, for example, distance  2525 , or a distance more or less than distance  2525 , rather than completely heat treating the entire length of the blade  2505  and handle connection means  2505 -A. In this case, as an example, the heat treatment area  2525  is shown only along one of the edges of the paint scraper blade  2505 . The heat treatment may be performed using, for example, the process described with respect to  FIG. 4  or a similar process for hardening the blade  2505  material so that at least the working edge is more durable, strong, and long lasting. As such, the blade  2505  may be cleaned along one or more sides to be heat treated as indicated shown by the dotted line area, for example area  2527 , prior to being heat treated. As noted above relative to other embodiments, one skilled in the art will appreciate that the present invention as embodied in the putty knife building construction tool, is made of a non-disposable blade construction preferably having the blade  2505  securely mounted to a handle  2510  and/or a handle connecting mechanism  2505 -A or rivets  2515  and  2520  (or structure welded to the blade and inserted into the handle) and the paint scraper will last longer and will not need to be thrown away or have the heat treated working edge  2525  of the blade  2505  reworked by, for example, manual or machine sharpening (i.e., not simply replacing the blade) as often. Therefore, using the present invention, standard paint scraper designs like shown in  FIG. 25 , that typically do not have quick replacement blade designs or constructions, last much longer before the working surface of the blade  2505  needs reworked of the entire paint scraper  2500  is thrown away and a new paint scraper  2500  is purchased to replace it. Note that  FIG. 25B  provides additional features, angle out side  2545  and cut out semicircle  2535  and their working surfaces. 
     Although a particular embodiment(s) of the present invention has been shown and described, it will be understood that it is not intended to limit the invention to the preferred embodiment(s) and it will be obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention. For example, the heating and cooling process of the present invention for hardening or strengthening blades may also be applied to other tools, for example, putty knifes, paint scrapers, notched margin trowels (V and/or square notches), notched taping knifes, brick trowels, pointing trowels, margin trowels, trowels with non-rectangular shaped blades, etc, where long term abrasive use may disadvantageously alter the original shape of the tool and/or tool blade. Further, other methods may be used for increasing the durability of the tools working edges (e.g., teeth, etc.), such as attaching (e.g., welding, adhesive, etc.) a more durable material to the tool blade as the work surface. Thus, the invention is intended to cover alternatives, modifications, and equivalents, which may be included within the spirit and scope of the invention as defined by the claims. 
     All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes