Patent Publication Number: US-2004055245-A1

Title: Wall cap corner aid

Description:
TECHNICAL FIELD  
       [0001] The present invention is a wall cap corner aid, in particular for use with stucco and/or plaster.  
       BACKGROUND ART  
       [0002] Generally, a person installing lath for plaster or stucco application on a wall or railing cap must install wire mesh on top of the cap and two separate welded wire corner aids or expanded metal corner beads to form the shape and provide grounds for the plaster or stucco. The wire and metal “u” shaped corners must be nailed on the top and sides of the opposing corner edges of the top of the wall or railing, generally a 2×4. This prior art wall cap creates a corner and top surface for plaster or stucco to be placed on the side and top of the wall.  
       [0003] Several common problems can occur with the prior art method and devices. For example, nails must be driven into the top of the wall and penetrate any waterproof membrane on the top of the wall. This can allow water to infiltrate through the membrane to the underlying wood framing. In turn, the wood framing can buckle, twist, warp and wrought causing cracking and de-lamination of the stucco/plaster system. Water protrusion can also cause discoloration of the stucco/plaster.  
       [0004] Another common problem associated with the prior art method and devices describe above is that the wire mesh can become flattened thereby eliminating the mechanical key needed for plaster/stucco to bond to lath or wire mesh. This can also cause de-lamination of the system.  
       [0005] Prior installations could also be problematic. For example, it is desirable for one screed edge to remain perpendicular to the other screed edge and for the depth or plaster ground to be consistent. The prior art mesh corner aids require significant time and effort to install and level with regard to these issues. Accordingly, an improved wall cap corner air that is easy to install, reduces cracking in the plaster or stucco, and does not need to be nailed on the top of the wall or railing is desired.  
       SUMMARY OF THE INVENTION  
       [0006] The present invention is a wall cap corner aid, in particular for use with stucco and/or plaster. The preferred embodiment of the invention is made from a metal lattice structure, preferably metal lath. The wall cap corner aid has a first leg joined to a concave center span at a metal edge corner. The corner is a discontinuity in the metal lattice structure made of smooth metal. A second leg is joined to the concave center span at a second smooth metal edge corner. Furthermore, the legs are preferably flexibly biased towards one another for mounting onto a base such as wall cap or a railing. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0007] The objects and features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages, may best be understood by reference to the following description, taken in connection with the accompanying drawings.  
     [0008]FIG. 1 is a side view of a preferred embodiment of the invention as installed.  
     [0009]FIG. 2 is a perspective view of a preferred embodiment of the invention.  
     [0010]FIG. 3 is a side view of a preferred alternate embodiment of the invention for a plaster relief aid.  
     [0011]FIG. 4 is a side cross-sectional view of a preferred embodiment of the invention installed on a railing.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0012] The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the general principles of the present invention have been defined herein specifically to provide an improved wall cap corner aid.  
     [0013] Referring now to FIG. 1, a preferred embodiment of a wall cap corner aid  10  is shown. The aid  10  is installed on a 2×4 cap  50  at the top of a wall  55  (or railing) to aid in the application of plaster or stucco to the wall. The aid  10  preferably has an M-shaped cross section as shown. In general, the aid  10  should have two legs  15 ,  20  joined by a concave central span  30 .  
     [0014] Preferably, the legs  15 ,  20  are flexibly biased towards one another so that the legs  15 ,  20  can cling to the wall  55  to which the aid  10  is mounted. Alternately, or additionally, the legs  15 ,  20  of the aid  10  can be nailed to the cap  50 . The aid  10  does not need to be nailed to the top of the cap  50 . Furthermore, the inward slope of the legs  15 ,  20  creates a clearance  60 , or “ground”, for application of plaster or stucco. The clearance  60  is typically ⅞ th  of an inch.  
     [0015]FIG. 4 shows an example of the aid  10  mounted to a railing  90  of a balcony at a house  100 . The aid  10  can be used, inter alia, to cap walls, railings and other plaster or stucco structures.  
     [0016] Referring to FIG. 2, a perspective view of a preferred embodiment of the invention  10  is shown. The aid  10  is preferably of unitary construction and made from a metal lattice structure such as metal lath. The metal lath is generally made from galvanized expanded metal that has been bent to the desired shape. Alternatively, the aid  10  can be constructed from, inter alia, plastic, woven wire and/or welded wire. The legs  15 ,  20  are joined to the concave central span  30  at edge corners  17  and  22 , respectively. Preferably, the corners are smooth (e.g. non-expanded) metal edge corners, each forming a discontinuity in the lattice. The non-expanded metal portions are set apart a predetermined distance so that they will form the smooth edge corners when the metal is bent to form the desired shape. The smooth corners are for screeding and reduce the potential for cracking in the plaster or stucco.  
     [0017] Referring to FIG. 3, a side view of an alternate embodiment is shown. Often, decorative features are applied to plaster or stucco walls. The designs are typically in relief from the wall&#39;s surface. The features are often referred to as “pop-outs” in the trade. Accordingly, the present invention can be used as an aid for forming relief surfaces or “pop-outs.” FIG. 3 depicts an aid  110  mounted to a base  140 . Preferably, the aid  110  is similar in construction to the wall cap corner aid  10  described above. However, the aid  110  preferably further comprises a mesh grip  145  at the end of each leg  115 ,  120 . The legs  115 ,  120  and mesh grips  145  grip the base  140  by the flexible bias of the expanded metal lath. The base  140  is preferably made of a light material that is easy to manipulate such as polystyrene, e.g. Styrofoam®, or some other light plastic. The aid  110  and base  140  can then be mounted to a wall to aid in forming a relief design.  
     [0018] The aid  110  and base  140  allow for more durable “pop-outs” via the complete covering of the “pop-out” with plaster or stucco, generally ⅞″. The improved “pop-out” also reduces the likelihood of water intrusion associated with prior art wood or foam-mesh pop-outs.  
     [0019] Thus, a wall cap corner aid, in particular for use with stucco and/or plaster is described above that reduces or eliminates common problems associated with plaster and stucco structures such as cracking and installation difficulties. The aid is relatively easy to install and level and it reduces the chance of cracking in plaster and/or stucco. In each of the above embodiments, the different positions and structures of the present invention are described separately in each of the embodiments. However, it is the full intention of the inventor of the present invention that the separate aspects of each embodiment described herein may be combined with the other embodiments described herein. Those skilled in the art will appreciate that adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.