Method and apparatus for cutting and polishing marble slabs

A machine is provided which automatically cuts and polishes disks of marble and finishes the edges of those disks. A marble cutting saw blade and a marble polishing wheel are disposed on a track located in spaced separation from a turntable. The turntable includes a central supporting pedestal and peripheral spacers which may be selectively located on a support to bear against the underside of a marble slab just within the diameter of a round disk which is to be cut therefrom. The sawing and polishing assemblies are mounted on separate carriages which move longitudinally along the track. The sawing and cutting assemblies can be adjusted vertically by means of separate, power driven drives. The speed of rotation of the turntable can be altered. An arbor is preferably located on the track between the two carriages to project toward the turntable. The arbor stabilizes the marble slab as it rotates with the turntable. Both the sawing and polishing assemblies are flushed with water to prevent chipping, suppress dust and increase the speed of cutting.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to methods and machines for use in cutting 
and finishing disks of marble from marble slabs or sheets. 
2. Desription of the Prior Art 
In the past the manufacture of disks of marble for use as table tops, 
pedestals, sculpture bases, and for other decorative and structural 
purposes has largely been carried out by hand. To manufacture a disk of 
marble according to conventional techniques, a slab of marble is placed 
upon a central support with the edges of the slab overhanging the support. 
A pattern is first traced by hand with a template upon the marble slab to 
be cut. Frequently the pattern is a circle, since slabs of marble of 
disk-shaped configuration are required more frequently than slabs of any 
other configuration. 
According to the conventional techniques, a workman proceeds to cut a disk 
of marble from the marble slab using a hand saw or a hand-held power saw 
to follow the circular pattern. Because marble is extremely hard, the 
procedure is very time consuming and tiring. As the workman tires the 
accuracy of conformity of cutting to the pattern often suffers. 
Furthermore, the pattern is frequently obscured by the dust produced from 
sawing, thereby making it even more difficult to follow the desired 
pattern. 
Once a marble disk has been cut from a slab, the edges of the marble must 
be ground with a polisher to impart a glossy appearance to the edges which 
will match the appearance of the flat expansive surfaces of the marble 
slab. According to conventional practice, this task likewise is performed 
by hand. Again, a workman with a hand-held manually operated or power 
driven abrasive tool, such as an electric sander, must manually sand the 
cut edges of the marble disk. This procedure is extremely labor intensive, 
time consuming, and therefore expensive. Furthermore, worker fatigue in 
finishing the edges of the cut marble slab sometimes results in only a 
mediocre finish on the cut marble edges. 
SUMMARY OF THE INVENTION 
In one broad aspect the present invention may be considered to be a new and 
improved method of manufacture. The method involves an automated procedure 
for cutting and polishing marble slabs for decorative and structural 
purposes. According to the invention an unfinished marble slab is mounted 
upon a turntable for rotation about a turntable axis. To facilitate 
handling and maximize stability the turntable axis is normally vertical, 
so that the turntable rotates in a horizontal plane. The turntable has a 
flat, disk-shaped support with a center pedestal thereon. The turntable 
also includes a plurality of locator apertures therethrough which are 
arranged in radial rays and in concentric circular rings about the center 
pedestal. A plurality of peripheral spacers are provided having bodies the 
same height as the center pedestal. The peripheral spacers also have 
locator pins which fit into the locator apertures in the disk-shaped 
support. 
According to the invention, one of the rings of locator apertures in the 
support is selected. The ring selected is of a diameter which is closest 
to, and less than a desired diameter of cutting of a marble slab. The ring 
of locator apertures selected must also be of a small enough diameter so 
that the saw blade will clear the bodies of the peripheral spacers. The 
peripheral spacers are then placed on the support with the locator pins 
thereof depending into the locator apertures of the selected ring to hold 
the peripheral spacers in position on the surface of the disk-shaped 
support. The unfinished marble slab is then placed upon the turntable and 
is supported from beneath by the center pedestal and the peripheral 
spacers. The bodies of the peripheral spacers support the marble slab just 
within the diameter of a round disk to be cut from the marble slab. 
A saw blade and a saw motor are mounted on a first carriage so that the saw 
blade is roatable about a blade axis perpendicular to the turntable axis. 
The first carriage is moved along a track that extends parallel to the 
turntable at a spaced separation therefrom. The saw blade is thereby 
positioned at a selected distance from the turntable axis on one side of 
the axis. The turntable and the saw blade are then rotated concurrently so 
that the saw blade cuts the slab along a circular pattern, leaving a round 
disk of the desired diameter supported from beneath by the center pedestal 
and the peripheral spacers. 
A polishing wheel and a polishing motor are mounted on a second carriage so 
that the polishing wheel is rotatable about a polishing wheel axis which 
is also perpendicular to the turntable axis. The second carriage is moved 
along the track to position the polishing wheel at the same selected 
distance from the turntable axis as the saw blade, but on the opposite 
side of the turntable axis therefrom. The turntable and the polishing 
wheel are then rotated concurrently so that the polishing wheel finishes 
the edge of the round disk previously cut by the saw blade. At the same 
time the polishing wheel is resiliently biased toward the edge of the 
round disk. A compressible, coil spring may be used for this support and 
disposed coaxially about the shaft which turns the polishing wheel. The 
spring bears against an annular bearing on the back of the polishing wheel 
and against the polishing wheel motor or motor support. 
In another broad aspect the invention may be considered to be a machine for 
cutting and polishing slabs of marble. The machine has a turntable. The 
turntable is comprised of a flat, rigid disk shaped support having a 
center pedestal thereon. A plurality of locator apertures are defined 
through the support and are arranged in concentric circular rings about 
the center pedestal. A plurality of peripheral spacers having bodies the 
same height as the center pedestal are also provided. The peripheral 
spacers also have locator pins which are adapted to fit into any selected 
locator aperture. In this way, the center pedestal supports the center and 
the peripheral supports support the periphery of the marble slab 
positioned thereon and which is to be cut and polished. 
Some means forming a track is located in spaced separation from the 
turntable to extend longitudinally parallel to the slab. A first carriage 
rides upon the track and a saw motor is mounted upon the first carriage. A 
saw blade driven in rotation by the saw motor is carried by the first 
carriage in a plane which intersects the marble slab. A first, power 
operated, vertical drive means is provided for automatically raising and 
lowering the saw blade relative to the turntable. 
The machine also has a second carriage which rides upon the track. A 
polishing motor is mounted upon the second carriage and a polisher driven 
by the polishing motor is carried by the second carriage to bear against 
the transverse edges of the cut marble slab. A compressible spring biasing 
means is interposed between the polisher and the polisher motor to urge 
the polisher toward the cut marble slab. A second power operated vertical 
drive means is provided for automatically raising and lowering the 
polisher and polisher motor relative to the turntable. The system includes 
a slab rotating means for rotating the marble slab about an axis 
perpendicular to the track. 
Preferably, the polisher is of an annular configuration with a concave 
center. The axis of rotation of the polisher is perpendicular to the axis 
of rotation of the turntable. The annular rim of the polisher is oriented 
in a generally vertical disposition, and the lower edge of the annular rim 
presses against the cut marble slab. The concave center of the polisher is 
therefore located above the marble slab. A water line is disposed and 
connected so as to direct a stream of water into the convex center of the 
polisher. This allows water to stay on the stone slab better. Flushing 
with water suppresses chipping and dust and increases the speed with which 
the edge of the slab can be polished. Preferably also, another water line 
is connected to direct a stream of water at the saw blade where the saw 
blade cuts the marble slab. 
An arbor is preferably mounted upon the track between first and second 
carriages to project toward the turntable coaxially along the axis of 
rotation of the marble slab. The purpose of the arbor is to stabilize the 
marble slab against the turntable as it rotates, so that the slab will not 
shift laterally during rotation. 
The system is also preferably provided with some means for adjusting the 
speed of rotation of the slab rotating means. Marble slabs of a greater 
thickness must be rotated more slowly than thinner slabs, since in forming 
thicker marble disks the saw blade and polishing wheel must dwell at each 
location along the perimeter of the marble disk for a greater period of 
time. 
The use of a power driven vertical drive in connection with the saw 
assembly mounting means allows the saw motor and the saw blade to be 
automatically moved together in transversely reciprocal fashion 
perpendicular to the orientation of the track. This allows slabs of a 
considerble thickness to be cut, since the saw blade can be progressively 
lowered to increasingly score the surface of the marble slab facing the 
track, each time the slab is rotated through a complete circle. Likewise, 
the polisher assembly mounting means is preferably provided with a power 
driven vertical drive so that the polishing motor and the polisher can be 
moved together upon the second carriage in transversely reciprocal fashion 
perpendicular to the track. The polisher assembly can likewise be advanced 
in a vertical direction and lengthwise along the cylindrical cut edge of 
the marble disk formed by the saw blade.

DESCRIPTION OF THE EMBODIMENT AND IMPLEMENTATION OF THE METHOD OF THE 
INVENTION 
An automatic marble slab finishing machine 10 is depicted in FIGS. 1 and 2. 
The machine 10 has a disk-shaped, rotatable turntable 12 adapted to carry 
a marble slab to be cut and polished. A marble slab 14 is depicted in 
position on the turntable 12 in FIG. 2. 
The turntable 12 is comprised of a flat, rigid disk shaped steel slab which 
serves as a support 13 and which is depicted in the plan view of FIG. 6. 
At the axis of rotation of the support 13 there is a raised, disk shaped 
pedestal 15 approximately six inches in diameter and two inches in height. 
The support 13 has a plurality of locator apertures 17 defined entirely 
therethrough. The locator apertures 17 are arranged in concentric circular 
rings or patterns about the center pedestal 15 and along eight radial rays 
which converge at the center pedestal 15. A plurality of peripheral 
spacers 19 are provided having cylindrical bodies 21 of the same height as 
the center pedestal. The bodies 21 are disk shaped and are about three 
inches in diameter. The peripheral spacers 19 each have a locator pin 23 
which is coaxial with the body 21 and extends downwardly therefrom. The 
locator pins 23 of the peripheral spacers 19 are adapted to fit into any 
selected locator aperture 17 in the support 13. In this way the center 
pedestal 15 supports the center of the marble slab 14 and the peripheral 
supports 19 support the periphery thereof, as depicted in detail in FIG. 
8. 
A motor 16 drives the turntable 12 in rotation though a speed adjusting 
mechanism 18, hereinafter to be described, and through a shaft and gearing 
system indicated generally at 20 in FIG. 2 The speed adjusting mechanism 
18 and the shaft and gearing system 20 reduce the rotational speed of the 
turntable 12 to only a small fraction of the speed of the motor 16. The 
axis of rotation of the turntable 12 is indicated at 30 in FIG. 2. The 
turntable axis 30 is vertical, so that the turntable 12 and the marble 
slab 14 are carried in a horizontal disposition. 
The machine 10 is constructed with a heavy steel frame 21 which supports 
the turntable 12. The frame 21 includes a track 22 which is disposed 
parallel to the turntable 12 in a horizontal disposition vertically above 
the turntable 12. The track 22 is supported in position by upright 
stanchions 24 and 25 at opposite ends of the machine 10. The stanchions 24 
and 25 rise from a base 26 of the frame 21 which is located beneath the 
turntable 12, and are stabilized relative to each other by a horizontal 
mounting platform 28 which has clearance beneath for the shaft and gearing 
system 20. 
The track 22, the upright stanchions 24 and 25, the mounting platform 28, 
and the base 26 together form the framework 21 upon which the other 
components of the machine 10 are mounted. All of the elements of the 
framework are constructed of heavy steel, so as to withstand the large 
forces which are necessary to properly machine marble slabs, such as the 
marble slab indicated at 14. 
A first carriage 32 is mounted for longitudinal reciprocal movement along 
the track 22. The carriage 32 includes a saw assembly mounting arm 34 
which is oriented perpendicualr to the track 22 and extends toward the 
turntable 12. The saw assembly mounting arm 34 carries a disk-shaped saw 
blade 36 in a plane perpendicular to the orientation of the turntable 12. 
The saw blade 36 is typically constructed of carborundum, or some other 
material conventionally used to cut marble. A water line 37 is connected 
to a source of water under pressure (not shown) to direct a stream of 
water at the saw blade 36 where it cuts into the marble slab 14. The 
stream of water suppresses chipping and dust and increases the speed of 
cutting. A 7.5 horsepower saw motor 38 is provided for driving the saw 
blade 36 through a belt drive system indicated at 40. The axis of rotation 
of the saw blade is indicated at 42 in FIG. 2, and is perpendicular to the 
turntable axis 30. With the system depicted, a marble disk three feet in 
diameter can be cut from a marble slab in from about five to about seven 
minutes. 
The carriage 32 is moved longitudinally along the track 22 by means of a 
hand wheel 41. The hand wheel 41 turns a pinion to drive the carriage 32 
along a rack on the track 22, so that the carriage 32 is moved along the 
track by conventional rack and pinion gearing. 
A second carriage 44 is also mounted for longitudinal reciprocal movement 
along the track 22 and includes a polishing assembly mounting arm 48. The 
polishing assembly mounting arm 48 extends toward the turntable 12 and 
carries a 2 horsepower polishing motor 46 and a polishing wheel 45 that 
also rotates about an axis perpendicular to the turntable axis 30. The 
polishing wheel axis is indicated at 50 in FIG. 2. 
The polishing wheel 45 is depicted in cross section in FIGS. 3 and 5 and is 
of a generally cup-shaped configuration with a concave center formed as a 
central, axial depression 47 and an annular rim 49 that serves as the 
polishing or grinding surface and is formed of abrasive material. As 
polishing proceeds, the polishing wheel 45 is changed from a rather coarse 
stone abrasive material to a polishing wheel of finer abrasive 
characteristics. Usually, three different grinding wheels are employed to 
produce the finished marble disk. As illustrated in FIG. 5, a resilient, 
compressible coil spring 51 is located behind the polished wheel 45 to 
push the polishing wheel toward the marble slab 14. The second carriage 44 
is positioned so that the spring 51 is slightly compressed between an 
annular bearing 57 at the backside of the polishing wheel 45 and the 
polishing motor 46 or a polishing motor support. When the polishing wheel 
45 is positioned in this fashion, constant repositioning of the second 
carriage 44 along the track 22 is unnecessary as the grinding face 49 of 
the polishing wheel 45 is worn down. Rather, the spring 51 ensures that 
sufficient friction exists against the edge of the marble slab 14, even as 
the grinding face 49 is worn away. The polishing wheel shaft 59 is driven 
by the polisher motor 46 through a splined connection, so that the shaft 
59 can move reciprocally to some extent. 
The annular grinding face 49 of the polishing wheel 45 is depicted in FIG. 
3. Another water line 53 is connected to a source of water under pressure 
(not shown) to direct a stream of water into the concave center 47 of the 
polishing wheel 45, as best depicted in FIG. 5. Because the polishing 
wheel 45 is formed with a central, axial depression 47, water tends to 
dwell therein and is supplied steadily to the grinding interface 55 at 
which the polishing wheel 45 contacts the marble slab 14. Flushing the 
grinding interface 55 copiously with water reduces heat, suppresses 
chipping and airborne dust and increases the speed with which edge of the 
marble slab 14 can be polished. 
The second carriage 44 is also moved along the track 22 by conventional 
rack and pinion gearing under the control of a hand wheel 47. To protect 
the rack and pinion gearing from marble dust and chips, and to thereby 
produce longer life and improve smoothness of operation, all of the 
working components of the rack and pinion gearing of both the first 
carriage 32 and the second carriage 44 are enclosed and shielded. 
An annular, upright drum-like pedestal 52 is mounted atop the platform 28 
at the center of the framework 21. The turntable 12 is supported on 
bearings and is driven in rotation by an upright, vertical drive shaft 54. 
Power is transmitted to the drive shaft 54 through a horizontal elongated 
shaft 56 to a bevel gear pinion 58. The pinion 58 turns a much larger 
bevel ring gear 60 that is rigidly secured to the drive shaft 54. The 
elongated shaft 56, in turn, is driven by a large pulley 62, located 
outside of the frame 21 beyond the stanchion 25. The pulley 62, in turn, 
is driven by a belt 64 from a much smaller pulley 66. The pulley 66 is 
driven by a large, rubber tired power take-off wheel 68, depicted in FIGS. 
2 and 4. 
The power take-off wheel 68 is oriented perpendicular to a power transfer 
disk 70, which is journaled for rotation in a mounting supported upon a 
vertical plate which forms a mounting bracket 72 that is reciprocably 
moveable relative to the stanchion 25 in the directions indicated by the 
directional arrows 78 in FIG. 4. The turntable drive motor 16 is also 
mounted upon the support bracket 72 and is coupled to drive the power 
transfer disk 70 by means of a V-belt 74, as best depicted in FIG. 4. 
Since the turntable drive motor 16 and the power transfer disk 70 can be 
shifted together as indicated by the directional arrows 78, the distance 
from the axis of rotation 79 of the power transfer disk 70 at which the 
power take-off wheel 68 rides is adjustable. In FIG. 2, the power take-off 
wheel 68 is shown as riding near the periphery of the power transfer disk 
70. As a result, the angular speed of rotation of the power take-off wheel 
68 is relatively great. If the turntable drive motor 16 and power transfer 
disk 70 are shifted to the left, as viewed in FIG. 4, the power take-off 
wheel 68 will ride on the surface of the power transfer disk 70 much 
closer to the axis of rotation 79 of the power transfer disc 70. The 
rotational speed of the power take-off wheel 68 will thereupon be 
significantly reduced. This speed reduction in turn reduces the speed of 
rotation of the bevel pinion 58 and bevel ring gear 60. The speed of 
rotation of the turntable 12 is thereupon reduced. 
It can thus be seen that one may adjust the speed of rotation of the 
turntable 12 by shifting the mounting bracket 72 to adjust the positon of 
the turntable drive motor 16 and the power transfer disk 70 in reciprocal 
fashion, as indicated by the directional arrows 78 in FIG. 4. The speed of 
rotation of the turntable 12 will be directly proportional to the 
magnitude of the distance from the axis of rotation 79 of the power 
transfer disk 70 at which the power take-off wheel 68 rides in contact 
with the surface of the power transfer disk 70. To reduce speed the 
turntable drive motor 16 and power transfer disk 70 are moved to the left 
as viewed in FIG. 4. To increase the speed of rotation of the power 
take-off wheel 68, the turntable drive motor 16 and power transfer disk 70 
are moved to the right as viewed in FIG. 4. At maximum turntable speed the 
power transfer disk 70 and the turntable drive motor 16 are at 
approximately the position depicted in FIG. 2. 
In the preferred embodiment of the invention the saw motor 38 and the saw 
blade 36 are both mounted upon the saw assembly mounting arm 34. The saw 
assembly mounting arm 34 is coupled to move upon the first carriage 32 in 
transversely reciprocal fashion perpendicular to the track 22. The saw 
motor 38 is rigidly secured to the saw assembly mounting arm 34, while the 
saw blade 36 is mounted upon an axle which is journaled to rotate within 
bearings in the saw assembly mounting arm 34. The saw motor 38 thereby 
drives the saw blade 36 in rotaiton about the saw blade axis 42 through 
V-belts 40 of fixed length. The saw motor 38, the saw blade 36, and the 
saw arm 34 are moveable in reciprocation together relative to the first 
carriage 32, perpendicular to the track 22 and parallel to the turntable 
axis 30. 
The saw assembly mounting arm 34 is moved in reciprocation by a first power 
operated drive means in the form of a stepper motor 43. The stepper motor 
43 is electrically operated and has a pinion which is mounted in a 
vertical plane and rotates about a horizontal axis. The pinion is engaged 
with a vertically oriented rack which extends the length of the saw 
assembly mounting arm 34. Rotation of the stepper motor pinion in one 
direction will drive the saw assembly mounting arm 34 vertically upwardly 
to lift the saw blade 36 relative to the turntable 12. When the stopper 
motor pinion is rotated in the opposite direction the saw blade 36 is 
lowered closer to the turntable 12. Control of the stepper motor 43 is 
preferably performed from a remote electrical switch box. 
In the same manner the polishing assembly mounting arm 48 can be moved 
vertically upwardly and downwardly by means of a corresponding second 
power operated vertical drive means such as the stepper motor 82. The 
stepper motor 82 automatically raises and lowers the polishing wheel 45 
and the polishing wheel motor 46 relative to the turntable. The stepper 
motor 82 likewise employs a rack and pinion mechanism like the stepper 
motor 43. Control of the stepper motor 82 is also performed from a remote 
electrical switch box. The stepper motor 82 is used to move the polishing 
assembly mounting arm 48 in transversely reciprocal fashion relative to 
the second carriage 44 and perpendicular to the track 22 and parallel to 
the turntable axis of rotation 30 by means of conventional rack and pinion 
gearing. 
The machine 10 is also equipped with an arbor 84 which has a downwardly 
directly turning tip 87. The turning tip 87 may be moved vertically 
downwardly to bear against the marble slab 14 through a conventional 
pressure pad 85, which has a conical indentation to seat the turning tip 
87 of the arbor 84 as depicted in FIG. 8. The arbor 84 is carried 
telescopically within an arbor sleeve 90, as illustrated in FIG. 2. The 
arbor 84 may be moved in vertically reciprocal fashion by means of 
conventional rack and pinion gearing under the control of a hand wheel 92. 
The arbor 84 is mounted on the track 22 by means of the arbor arm 90 
between the first and second carriages 32 and 44. The arbor 84 projects 
toward the mounting base 52 coaxially along the axis of rotation 30 of the 
marble slab 14 and the turntable 12 to stabilize the marble slab 14 as it 
rotates. 
The unique design of the turntable 13 provides great flexibility, 
versitility and efficiency in cutting and polishing marble disks from 
marble slabs. As previously noted, it is highly desirable for the 
peripheral spacers 19 to be located at locator apertures 17 closest to and 
just within the desired diameter of cutting of a marble slab. That is, for 
example, if a marble slab is to have a diameter 95, depicted in phantom in 
FIG. 6, the peripheral spacers 19 should be located just within the 
diameter 95, as depicted in FIG. 6. The saw blade 36 will thereby pass in 
a circular path just outside of the bodies 21 of the peripheral spacers 
19. The peripheral spacers 19 are thereby able to provide solid support to 
the periphery of the marble disk to be cut. This stabilizes the marble 
slab 14 at the most important location, which is the line of cutting. 
The turntable 12 may be utilized with virtually any diameter of marble disk 
to be cut. When a marble disk of a different size is to be cut, the 
peripheral spacers 19 are merely lifted from the support 13 to disengage 
the locator pins 23 from the locator apertures 17. The desired concentric 
ring of locator apertures 17 is then selected, and the peripheral spacers 
19 are then each engaged in one of the locator apertures 17 in the 
selected ring of apertures by simply inserting the locator pin 23 thereof 
in a selected locator aperture 17. 
The unique design of the turntable 12 allows virtually any different size 
of marble disk to be efficiently supporting during the cutting and 
grinding operation. Solid support at the periphery of the marble disk 
increases the speed of cutting, as well as the finish which is obtained in 
both cutting and polishing. Thus, the unique turntable 12 provides the 
marble cutting machine of the invention with greatly improved versatility 
and efficiency. 
In the operation of the machine 10 according to the method of the 
invention, the saw assembly mounting arm 34, the arbor 84 and the 
polishing assembly mounting arm 48 are all withdrawn vertically upwardly 
and away from the turntable 12. An uncut marble slab 14 is then positioned 
atop the turntable 12. The perimeter of the marble slab 14 is typically of 
irregualar shape, but the slab 14 is centered insofar as possible upon the 
axis of rotation 30 atop the turntable 12, to minimize waste. The hand 
wheel 92 is then turned to drive the arbor 84 vertically downwardly within 
the arbor sleeve 90 so that the arbor 84 bears against the marble slab 14 
through the turning tip 87 and the pressure pad 85. The turning tip 87 is 
coaxially aligned with the turntable axis 30. 
The first carriage 32 is then moved along the track 22 parallel to the 
turntable 12 at a spaced separation therefrom by means of the hand wheel 
41 to position the saw blade 36 at a selected distance from the turntable 
axis 30 on one side thereof. The distance is determined by the radius of 
the marble disk to be produced. The position of the saw assembly arm 34 is 
then vertically adjusted by the stepper motor 43 to bring the saw blade 36 
into contact with the marble slab 14. The saw blade 36 and the turntable 
12 are thereupon concurrently rotated. As sawing commences, the saw 
assembly arm 34 is moved vertically downwardly by means of the stepper 
motor 43 so that the saw blade 36 cuts into the marble slab 14. The saw 
blade 36 is rotated at a much higher speed than the turntable 12. After 
the turntable 12 has rotated through a number of circular revolutions and 
the saw blade 36 has trimmed the irregular edges from the marble slab 14, 
a marble disk is left. The peripheral spacers 19 provide solid support to 
the marble slab 14 proximate to the path of cutting during the cutting 
operation. The stepper motor 43 may thereupon be operated to withdraw the 
first carriage 32 away from the marble slab 14 so as to avoid interference 
in the polishing operation from the saw blade 36. 
The second carriage 44 is then moved along the track 22 by means of the 
hand wheel 47 to position the polishing wheel 45 at the same selected 
distance from the turntable axis 30 as the saw blade 36 was previously 
positioned with the spring 51 compressed. The polishing wheel 45 is 
located on the side of the turntable axis 30 opposite the saw blade 36 so 
that the movements of the carriages 32 and 44 do not bring the saw blade 
36 and the polishing wheel 45 into interference with each other. The 
stepper motor 82 is used to vertically adjust the position of the 
polishing wheel 45 relative to the cut edge of the marble slab 14. The 
polishing wheel 45 should be located as depicted in FIG. 5, with the lower 
edge of the polishing face 49 in contact with the edge of the marble slab 
14 to be polished. This allows a stream of water to be supplied through 
the water line 53 into the concave center 47 of the polishing wheel 45. By 
supplying a stream of water to this cup-shaped depression, a greatly 
enhanced flushing effect is achieved. This results in a smoother finish, 
increased speed of polishing and a suppression of dust and chipping. 
The turntable 12 and the polishing wheel 45 are then concurrently rotated 
so that the polishing wheel 45 finishes the edge of the round marble disk 
left from the slab 14. The coil spring 51 ensures that the polishing face 
49 of the polishing wheel 45 maintains contact with the edge of the marble 
slab 14. The polishing wheel 45 is driven at a much greater angular speed 
than the turntable 12. When the cylindrical peripheral edge of the marble 
disk has been satisfactorily finished, the hand wheel 47 is operated to 
laterally move the second carriage 44 to withdraw the polishing wheel 45 
from the marble disk created from the marble slab 14. The hand wheel 92 is 
then operated to withdraw the arbor 84 vertically upward, and the finished 
marble disk is removed from the turntable 12. 
Depending upon the thickness of the marble slab 14, and the speed of 
rotation of the saw blade 36 and the polishing wheel 45, an adjustment in 
turntable speed may be desirable. Adjustment of the speed of rotation of 
the turntable 12 on the turntable axis 30 is achieved in the manner 
previously described. That is, the mounting bracket 72 carrying the 
turntable drive motor 16 and power transfer disk 70, is shifted to the 
left, as viewed in FIG. 4, to reduce the speed of rotation of the 
turntable 12. To increase the speed of turntable rotation, the mounting 
bracket 72 is shifted to the right as viewed in those drawing figures. 
Undoubtedly, numerous variations and modifications of the invention will 
become readily apparent to those skilled in the art of manufacturing 
marble disks from marble slabs. For example, other conventional mechanical 
linkages may be substituted for the rack and pinion gearing, the 
telescoping mechanism, and the drive shaft and gearing employed in the 
embodiment of the machine of the invention depicted in the drawings. 
Accordingly, the scope of the invention should not be construed as limited 
to the specific embodiment and implementation of method described herein, 
but rather is defined in the claims appended hereto.