U.S. patent application number 11/034931 was filed with the patent office on 2006-07-13 for stainless steel tool and method of forming.
This patent application is currently assigned to Bon Tool Company. Invention is credited to Carl A. Bongiovanni.
Application Number | 20060150357 11/034931 |
Document ID | / |
Family ID | 36651699 |
Filed Date | 2006-07-13 |
United States Patent
Application |
20060150357 |
Kind Code |
A1 |
Bongiovanni; Carl A. |
July 13, 2006 |
Stainless steel tool and method of forming
Abstract
Mortar joint finishing tools, such as jointers, beaders, and
sledrunners are disclosed. The tools may include a stainless steel
body. The tools and may be formed by a method such as casting,
forging, or stamping.
Inventors: |
Bongiovanni; Carl A.;
(Allison Park, PA) |
Correspondence
Address: |
THE LAW OFFICE OF RICHARD W. JAMES
25 CHURCHILL ROAD
CHURCHILL
PA
15235
US
|
Assignee: |
Bon Tool Company
|
Family ID: |
36651699 |
Appl. No.: |
11/034931 |
Filed: |
January 13, 2005 |
Current U.S.
Class: |
15/235.3 |
Current CPC
Class: |
E04F 21/1652
20130101 |
Class at
Publication: |
015/235.3 |
International
Class: |
E04G 21/20 20060101
E04G021/20 |
Claims
1. A mortar joint finishing tool, comprising: a cast stainless
steel first mortar-contacting element having a first
mortar-contacting surface, the first mortar-contacting surface
having a first contour; and a cast stainless steel second
mortar-contacting element adjacent the first mortar-contacting
element and having a second mortar-contacting surface, the second
mortar-contacting surface having a second contour.
2. The mortar joint finishing tool of claim 1, wherein the casting
is investment casting.
3. The mortar joint finishing tool of claim 1, wherein the first
mortar-contacting element and the second mortar-contacting element
are polished.
4. The mortar joint finishing tool of claim 1, wherein the first
contour is convex.
5. The mortar joint finishing tool of claim 1, wherein the first
contour is concave.
6. The mortar joint finishing tool of claim 1, wherein the first
mortar-contacting element has a longitudinal axis and a
cross-section, the cross-section a plane taken perpendicular to the
longitudinal axis, wherein the cross-section is shaped as a
"U."
7. The mortar joint finishing tool of claim 1, wherein the first
mortar-contacting element has a longitudinal axis and a
cross-section, the cross-section a plane taken perpendicular to the
longitudinal axis, wherein the cross-section is shaped as a
"V."
8. The mortar joint finishing tool of claim 1, wherein the first
contour is different than the second contour.
9. The mortar joint finishing tool of claim 1, wherein the
stainless steel is martensitic stainless steel.
10. The mortar joint finishing tool of claim 1, wherein the
stainless steel is austenitic stainless steel.
11. The mortar joint finishing tool of claim 1, further comprising
a cast stainless steel connecting element extending between the
first mortar-contacting element and the second mortar-contacting
element.
12. The mortar joint finishing tool of claim 11, wherein the
connecting element is formed with the first mortar-contacting
element and the second mortar-contacting element.
13. A cast stainless steel jointer comprising: a first element
having a first surface, the first surface having a first contour
configured to impart a first indent in an unfinished mortar joint;
a second element having a second surface, the second surface having
a second contour configured to impart a second indent in the
unfinished mortar joint; and a connecting element that extends
between the first element and the second element.
14. The cast stainless steel jointer of claim 13, wherein the
casting is investment casting.
15. The cast stainless steel jointer of claim 13, wherein the first
element has a first shape, and the second element has a second
shape, and wherein the first shape is different than the second
shape.
16. The cast stainless steel jointer of claim 13, wherein the first
contour is different than the second contour.
17. A sledrunner comprising a stainless steel body that comprises:
an elongated mortar-contacting element having a mortar-contacting
surface; and a handle support affixed to the elongated
mortar-contacting element and configured for fastening to a
handle.
18. The stainless steel sledrunner of claim 17, wherein the handle
support comprises two brackets adapted for fastening to a
handle.
19. The stainless steel sledrunner of claim 17, wherein the
stainless steel sledrunner is formed by casting.
20. The stainless steel sledrunner of claim 19, wherein the casting
is investment casting.
21. The stainless steel sledrunner of claim 17, wherein the
stainless steel sledrunner is formed by forging.
22. The stainless steel sledrunner of claim 17, wherein the
stainless steel sledrunner is formed by stamping.
23. A stainless steel beader comprising: a first stainless steel
element having a first surface, the first surface having a first
contour configured to impart a first form to an unfinished mortar
joint; and a second stainless steel element adjacent the first
stainless steel element and having a second surface, the second
surface having a second contour configured to impart a second form
to the unfinished mortar joint.
24. The stainless steel beader of claim 23, wherein the stainless
steel beader is formed by casting.
25. The stainless steel beader of claim 23, wherein the casting is
investment casting.
26. The stainless steel beader of claim 23, wherein the stainless
steel beader is formed by forging.
27. The stainless steel beader of claim 23, wherein the stainless
steel beader is formed by stamping.
28. The stainless steel beader of claim 23, wherein the first
element has a first shape, and the second element has a second
shape that is different than the first shape.
29. The stainless steel beader of claim 23, wherein the first
contour is different than the second contour.
30. The stainless steel beader of claim 23, wherein the first
contour is convex.
31. The stainless steel beader of claim 23, further comprising a
stainless steel connecting element extending between the first
stainless steel element and the second stainless steel element.
32. The stainless steel beader of claim 31, wherein the connecting
element is formed with the first stainless steel element and the
second stainless steel element.
33. A method for manufacturing a mortar joint finishing tool,
comprising casting a unitary body of stainless steel that comprises
a first mortar-contacting element having a first mortar-contacting
surface adjacent a second mortar-contacting element having a second
mortar-contacting surface.
34. The method of claim 33, wherein the casting is investment
casting.
Description
BACKGROUND OF THE INVENTION
[0001] Finishing tools are applied to masonry or masonry mortar
joints during construction to treat the masonry or mortar joints.
These tools include jointers, sledrunners, and beaders, which
contact unhardened mortar in joints during operation to provide a
finish.
SUMMARY OF THE INVENTION
[0002] The present invention is directed to masonry mortar joint
finishing tools, such as various types of jointers, sledrunners,
and beaders. In one embodiment, a masonry mortar joint finishing
tool includes a stainless steel ("stainless steel" refers herein to
various known or future developed stainless steel alloys) body. The
jointer includes a cast stainless steel first mortar-contacting
element having a first mortar-contacting surface with a first
contour. The jointer may further include a second mortar-contacting
element adjacent the first mortar-contacting element and having a
second mortar-contacting surface with a second contour. A
connecting element may be formed to and between the first
mortar-contacting element and the second mortar-contacting element
in an embodiment.
[0003] The body's stainless steel form provides high strength,
hardness, and durability, and a high corrosion resistance which
should remain high even after surface wear and damage.
[0004] The body may be manufactured by a method that provides
further advantageous properties. One method may be casting, which
provides good dimensional repeatability among multiple manufactured
bodies. Another method may be forging, which provides a body with
high directional strength, structural integrity, and toughness. Yet
another method of manufacture may be stamping, which provides a
body at a lower production cost and a lower material cost.
[0005] In another embodiment, a cast stainless steel jointer
includes a first element with a first surface, wherein the first
surface has a first contour configured to impart a first shape or
indent in an unfinished mortar joint. The jointer may also include
a second element having a second surface, wherein the second
surface has a second contour configured to impart a second shape or
indent in the unfinished mortar joint. The jointer may also include
a connecting element that extends between the first element and the
second element.
[0006] In another embodiment, a sledrunner includes a stainless
steel body that includes an elongated mortar-contacting element
having a mortar-contacting surface and a handle support affixed to
the elongated mortar-contacting element and configured for
fastening to a handle.
[0007] In another embodiment, a stainless steel beader includes a
first element having a first surface, wherein the first surface has
a first contour configured to impart a first form to an unfinished
mortar joint. The beader may also include a second element having a
second surface, wherein the second surface has a second contour
configured to impart a second form to the unfinished mortar joint.
A connecting element may extend between the first element and the
second element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The detailed description is better understood in conjunction
with the accompanying drawings, in which like reference characters
represent like elements, as follows:
[0009] FIG. 1 is a perspective view of an embodiment of a
jointer;
[0010] FIG. 2 is a side view of the embodiment of FIG. 1;
[0011] FIG. 3 is a left end view of the embodiment of FIG. 1;
[0012] FIG. 4 is a right end view of the embodiment of FIG. 1;
[0013] FIG. 5 is a top view of the embodiment of FIG. 1
[0014] FIG. 6 is a perspective view of another embodiment of a
jointer;
[0015] FIG. 7 is a side view of the embodiment of FIG. 6;
[0016] FIG. 8 is a top view of the embodiment of FIG. 6;
[0017] FIG. 9 is a perspective view of an embodiment of a
sledrunner;
[0018] FIG. 10 is a side view of the embodiment of FIG. 9;
[0019] FIG. 11 is a left end view of the embodiment of FIG. 9;
[0020] FIG. 12 is a top view of the embodiment of FIG. 9;
[0021] FIG. 13 is a perspective view of an embodiment of a
beader;
[0022] FIG. 14 is a side view of the embodiment of FIG. 13;
[0023] FIG. 15 is a left end of the embodiment of FIG. 13;
[0024] FIG. 16 is a right end view of the embodiment of FIG. 13;
and
[0025] FIG. 17 is a top view of the embodiment of FIG. 13.
DETAILED DESCRIPTION
[0026] Because of the demands inherent in their operation, the
bodies of jointers, sledrunners, and beaders are subject to
deterioration.
[0027] Cast zinc alloys, malleable iron, and brass alloys, such as
bronze, are forms used for the bodies of jointers, sledrunners, and
beaders. But, because the strength, hardness, and corrosion
resistance of these materials is mediocre, bodies made from these
materials still lack durability over prolonged use.
[0028] Another material used in the main bodies of jointers,
sledrunners, and beaders is high carbon steel. However, high carbon
steel lacks good corrosion resistance, decreasing the durability of
bodies made from this material.
[0029] Additionally, the bodies of jointers, sledrunners, and
beaders are commonly sanded or ground to a finish, resulting in
rough surfaces that cause friction when slid against mortar during
operation.
[0030] One method of improving the durability of jointers,
sledrunners, and beaders is to coat them with a corrosion-resistant
material. For example, a body of a jointer may be plated with
chromium, which has good corrosion resistance. However, the coating
will eventually wear off from use.
[0031] In one embodiment of a masonry mortar joint finishing tool
as shown in FIGS. 1-5, a jointer 10 includes a stainless steel body
20 that includes a first mortar-contacting element 30, a second
mortar-contacting element 40, and a connecting element 50 that
extends between the first and second mortar-contacting elements 30
and 40.
[0032] FIG. 2 shows a side view of the body 20 of the jointer 10.
The body 20 may be shaped in an "S" configuration as shown from the
perspective of FIG. 2. The first mortar-contacting element 30 may
be parallel to the second mortar-contacting element 40 as shown
from the perspective of FIG. 2, if desired. However, the body 20
may be differently shaped. For example, the body 20 may be shaped
as any of various sigmoid configurations, where the first and
second mortar-contacting elements 30 and 40 are or are not
parallel, and the body 20 is symmetrical or asymmetrical.
[0033] The body 20 may also be shaped such that the connecting
element 50 is variously angled with respect to the first and second
mortar-contacting elements 30 and 40. For example, the connecting
element 50 may have first and second portions 52 and 54 that are
rounded as viewed from the perspective of FIG. 2. Alternatively,
the first and second portions 52 and 54 may be shaped such that the
connecting element 50 forms distinct angles with respect to the
first and second mortar-contacting elements 30 and 40. The
connecting element 50 may also be flat or otherwise shaped in a
middle portion 56.
[0034] The first mortar-contacting element 30 in the embodiment of
FIGS. 1-5 includes a first end 32 and a first outer surface 34.
From the perspective of FIG. 2, the first end 32 and the first
outer surface 34 may intersect such that the angle between them is
less than 90 degrees. However, various angles may be employed. A
portion or all of the first outer surface 34 in this embodiment
contacts unfinished mortar during operation of the jointer 10,
dependent upon the size of the mortar joint.
[0035] FIG. 3 shows a left end view of the jointer 10. From the
perspective of FIG. 3, and taken as a plane perpendicular to the
longitudinal axis of the first mortar-contacting element 30, the
first mortar-contacting element 30 in this embodiment has a "U"
shaped cross section, and the mortar-contacting first outer surface
34 has a cross-section that has a convex, "U" contour. Thus, during
operation of the jointer 10, the cross-sectional "U" contour of the
outer surface 34 may be pressed and/or slid against unhardened
mortar in a masonry construction to impart a rounded, concave
indent to the mortar.
[0036] However, the cross-sections of the shape of the first mortar
contacting element 30 and the contour of the first outer surface 34
may be variously designed, such as with cross-sections having a "V"
shape and contour, a "T" shape and square or step contour, a hollow
or solid square shape and flat contour, a hollow, solid, or half
circle shape and half-circle contour, an oval shape and half-oval
contour, or another shape and/or contour as desired. The various
designs for cross-sectional contours of the first outer surface 34
may impart different indents to unhardened mortar during operation
of the jointer 10.
[0037] The second mortar-contacting element 40 in the embodiment of
FIGS. 1-5 includes a second end 42, and a mortar-contacting
surface, the second outer surface 44. From the perspective of FIG.
2, the second end 42 and the second outer surface 44 may intersect
such that the angle between them is less than 90 degrees. However,
as with first end 32 and the first outer surface 34, various angles
may be employed. From the perspective of FIG. 2, the angle between
the second end 42 and the second outer surface 44 may be the same
as or different than the angle between the first end 32 and the
first outer surface 34.
[0038] In another embodiment, the jointer 10 does not include the
connecting element 50, and the first and second mortar-contacting
elements 30 and 40 abut.
[0039] In another embodiment that is not illustrated, the
connecting element 50 of the jointer 10 includes a protruding
threaded element at each of its ends, for coupling with replaceable
first and second mortar-contacting elements 30 and 40. The first
and second mortar-contacting elements 30 and 40 in this embodiment
have apertures with complementary threading to that of the
connecting element 50, such that they may be screwed onto the
connecting element 50. The first and second mortar-contacting
elements 30 and 40 may be replaced by other threaded
mortar-contacting elements of various sizes and shapes. Other
coupling configurations may alternately be used. Such a jointer may
be configured and shaped like a "barrel" jointer, as known in the
art.
[0040] In another embodiment that is not illustrated, the jointer
10 does not include the second mortar-contacting element 40, and
instead includes a handle, such as a cylindrical wooden or plastic
handle, in its place. The handle may be secured to or around a
portion of the body 20, such as by epoxy and/or interference fit.
The body 20 may extend into an opening in the handle, to facilitate
the securing.
[0041] FIG. 4 shows a right end view of the jointer 10. From the
perspective of FIG. 4, and taken as a plane perpendicular to the
longitudinal axis of the second mortar-contacting element 40, the
second mortar-contacting element 40 in this embodiment has a "U"
shape cross section, and the cross-section of the second outer
surface 44 has a convex, "U" contour. The cross-sectional shape of
the second mortar-contacting element 40 may be different than that
of the first mortar-contacting element 30, and may have any of the
shapes mentioned with respect to the first mortar-contacting
element 30, as described above, or another shape. The curved
portion of the cross-sectional "U" contour of the second outer
surface 44 may have a different radius than the curved portion of
the cross-sectional "U" contour of the first outer surface 34.
Thus, where the second outer surface 44 is pressed and/or slid
against unhardened mortar, the shape of the imparted indent may be
different than that imparted by the first outer surface 34. The
second outer surface 44 may also have a cross-sectional contour
other than a "U," such as described with respect to the first outer
surface 34.
[0042] FIG. 5 shows a top view of the jointer 10. From this
perspective, the body 20 may be straight as shown, or a different
shape. The connecting element 50 may be bowed.
[0043] FIGS. 6, 7, and 8 show a perspective, side, and top view,
respectively, of an example of a jointer with mortar-contacting
elements with different shapes and contours. In this embodiment, a
bullhorn jointer 110 includes a first mortar-contacting element 130
having a first mortar-contacting surface, the first outer surface
134. The bullhorn jointer 110 illustrated in that embodiment also
includes a second mortar-contacting element 140 having a second
mortar-contacting surface, the second outer surface 144.
[0044] The first mortar-contacting element 130 in this embodiment
has a rounded shape that bends toward its end 132 as shown from the
perspective of FIG. 7, and narrows toward its end 132 as shown from
the perspectives of FIGS. 6, 7 and 8. The cross-sectional shape of
the first mortar-contacting element in this embodiment, as taken as
a plane perpendicular to the longitudinal axis of the first
mortar-contacting element 130, is a solid circle or solid oval that
becomes smaller nearer the end 132. The cross-section of the outer
surface 134 in this embodiment is thus configured as a circle or
oval that is smaller nearer the end 132, and may impart a narrow,
rounded indent in unhardened mortar in a mortar joint.
[0045] The second mortar-contacting element 140 in this embodiment
also has a circular or oval cross-sectional shape, but the shape
does not narrow toward the second end 142. Thus, the cross-section
of the mortar-contacting surface, outer surface 144, is circular or
oval and may impart a rounded indent in unhardened mortar that is
larger than that imparted by the outer surface 134.
[0046] In another embodiment of a masonry mortar joint finishing
tool as shown in FIGS. 9-12, a sledrunner 210 includes a stainless
steel body 220 that includes a mortar-contacting element 230, and a
handle support 240 affixed to the mortar-contacting element 230 and
configured for fastening to a handle. A handle 250 may be fastened
to the handle support 240.
[0047] FIG. 10 shows the side view of the body 220 of the
sledrunner 210. The mortar-contacting element 230 in this
embodiment is elongated, and straight over most of its length, as
shown from the perspective of FIG. 10. But, the mortar-contacting
element 230 may be curved or angled up at its first end 232 and
second end 234, which may facilitate sliding of the sledrunner 210.
In this embodiment, the mortar-contacting element 230 includes an
elongated mortar-contacting surface, the outer surface 236. The
outer surface 236 length, which may span much or all the distance
between the first end 232 and the second end 234, may facilitate
operation of the sledrunner 210 on long mortar joints.
[0048] FIG. 11 shows a front end view of the sledrunner 210. From
this perspective, and taken as a plane perpendicular to the
longitudinal axis of the mortar-contacting element 230, the
mortar-contacting element 230 in this embodiment has a
cross-section having a "V" shape, and the outer surface 236 has a
cross-section that has a "V" contour. However, these cross-sections
may be different, such as described with respect to the first
mortar-contacting element 30 and first outer surface 34 of the
jointer 10 in FIGS. 1-5, or in other embodiments.
[0049] Returning to FIG. 10, the sledrunner 210 in this embodiment
includes a handle support 240, which may be attached to or formed
on and project from the top surface 260 of the mortar-contacting
element 230. The handle support 240 may include a first bracket 242
having a first aperture 244, and a second bracket 246 having a
second aperture 248. The handle support 240 may be affixed to the
top surface 260 in various ways. For example, the handle support
240 may include an anchoring member 249 that is affixed to the top
surface 260. The anchoring member 249 may be stainless steel or
another material and may be flat or may conform in shape to the top
surface 260. The anchoring member may extend between and be affixed
to the first bracket 242 and the second bracket 246.
[0050] In one embodiment, the first bracket 242, second bracket
246, and anchoring member 249 may be formed as a unitary structure.
The anchoring member 249 may then be secured to the top surface 260
by solder, weld, or another method. The body 220 may also be formed
as a unitary structure that includes a handle support 240 that does
not include an anchoring member 249, such as where the body 220 is
cast or forged.
[0051] In another embodiment that is not illustrated, the body 220
may be formed as a unitary structure that includes a handle support
for securing to a handle. The handle may be secured to or around a
portion of the handle support, such as by epoxy and/or interference
fit. The handle support may extend into an opening in the handle,
to facilitate the securing. In this embodiment, the body 220,
handle support, and handle may be configured as and into the shape
of a "loop" sledrunner, as known in the art, in which the handle
support includes a portion that extends, in the shape of a curve,
from one end of the body 220 to the handle.
[0052] Returning to the embodiment shown in FIGS. 9-12, a handle
250 may be secured to the first and second brackets 242 and 246
through their apertures 244 and 248, respectively, such as by
screws or a bolt.
[0053] FIG. 12 shows a top view of the sledrunner 210. As viewed
from this perspective, the handle 250 may be positioned at the
center of the mortar-contacting element 230, or off-center.
[0054] In another embodiment of a masonry mortar joint finishing
tool as shown in FIGS. 13-17, a beader 310 includes a stainless
steel body 320 that includes a first mortar-contacting element 330,
a second mortar-contacting element 340, and a connecting element
350 that extends between the first and second mortar-contacting
elements 330 and 340.
[0055] FIG. 14 shows the body 320 of the beader 310. In this
embodiment the body 320 is shaped in an "S" configuration as shown
from the perspective of FIG. 14. The first mortar-contacting
element 330 is also parallel to the second mortar-contacting
element 340 in this embodiment. The connecting element 350 may have
first and second portions 352 and 354 that are rounded as viewed
from the perspective of FIG. 14.
[0056] However, the body 320 may have a different shape as viewed
from the perspective of FIG. 14, such as any shape described with
respect to the jointer 10 as viewed from the perspective of FIG. 1.
Thus, the body 320 may have different shapes and angles with
respect to its first mortar-contacting element 330, second
mortar-contacting element 340, and connecting element 350.
[0057] The first mortar-contacting element 330 in the embodiment of
FIGS. 13-17 includes a first end 332 and a first inner surface 334.
From the perspective of FIG. 14, the first end 332 and the first
base 333 of the first inner surface 334 may intersect such that the
angle between them is 90 degrees. However, various angles may be
employed. Likewise, the second end 342 and the second base 343 of
the second inner surface 344 may intersect at a 90 degree angle, or
another angle.
[0058] A portion or all of the first inner surface 334 in this
embodiment may contact unhardened mortar in a mortar joint during
operation of the beader 310.
[0059] FIG. 15 shows a left end view of the beader 310. From the
perspective of FIG. 15, and taken as a plane perpendicular to the
longitudinal axis of the first mortar-contacting element 330, the
first mortar-contacting element 330 in this embodiment has a "U"
shaped cross section, and the first inner surface 334 has a
cross-section that is a concave, "U" shaped contour. Thus, during
operation of the beader 310, the "U" shaped contour of the first
inner surface 334 may be pressed and slid against unhardened mortar
in a masonry construction to impart a rounded, convex form in the
mortar. Thus, a beader may provide a raised mortar joint, whereas a
jointer may provide an indented mortar joint.
[0060] However, the cross-sectional shape of the first
mortar-contacting element 330 and the cross-sectional contour of
the first inner surface 334 may be different, such as a "V" shape
and contour, a hollow square shape and square contour, a hollow
half-circle shape and half-circle contour, a half-oval shape and
half-oval contour, or another shape and/or contour as desired. The
various alternatives for cross-sectional contours of the first
inner surface 334 may impart different forms to unhardened mortar
during operation of the beader 310.
[0061] FIG. 16 shows a right end view of the beader 310. From the
perspective of FIG. 16, and taken as a plane perpendicular to the
longitudinal axis of the second mortar-contacting element 340, the
second mortar-contacting element 340 in this embodiment has a "U"
shape cross section, and the second outer surface 344 has a
cross-section that has a convex, "U" contour. The shape of the
second mortar-contacting element 340 may be different than that of
the first mortar-contacting element 330. The curved portion of the
cross-sectional "U" contour of the second outer surface 344 may
have a different radius than the curved portion of the
cross-sectional "U" contour of the first outer surface 334. Thus,
where the second outer surface 344 is pressed and slid against
unhardened mortar, the shape of the imparted form may be different
than that imparted by the first outer surface 334. The second outer
surface 344 may have another cross-sectional contour, such as
described with respect to the first outer surface 334, to impart a
form to unfinished mortar.
[0062] In another embodiment not illustrated, the beader 310 does
not include the second mortar-contacting element 340, and instead
includes a handle, such as a cylindrical wooden or plastic handle,
in its place. The handle may be secured to or around a portion of
the body 320, such as by epoxy and/or interference fit. The body 20
may extend into an opening in the handle to facilitate the
securing.
[0063] FIG. 17 shows a top view of the beader 310. From this
perspective, the body 320 may be straight as shown, or a different
shape. The connecting element 350 may be bowed.
[0064] Constructing the body of a masonry mortar joint finishing
tool with stainless steel ("stainless steel" refers herein to
various known or future developed stainless steel alloys) provides
many advantageous properties in comparison to constructions with
other metals, such as zinc alloys, malleable iron, and brass
alloys, such as bronze. These properties are due, in part, to the
high chromium content of stainless steel, which contributes to its
high hardness, and its wear and corrosion resistance.
[0065] The corrosion-resistant properties of stainless steel
include the ability of stainless steel to inherently form a
protective film of chromium-rich oxide at its surfaces. If the
surface film is penetrated or worn away due to chipping,
scratching, or other surface-damage, the newly-exposed surface may
spontaneously regenerate a surface film in the presence of the
oxygen in air. This property provides an advantage in stainless
steel over a different metal body that is plated with
corrosion-resistant material, since when the plating wears off from
use, that other metal body's corrosion resistance may significantly
decrease, and its surface hardness may suffer with use. The surface
hardness of stainless steel, however, typically remains high even
after prolonged use.
[0066] The material of the masonry mortar joint finishing tool body
in any of the above embodiments may be a stainless steel grade in
the 400 series. Series 400 grades are martensitic stainless steels
and have high hardness, impact strength and corrosion resistance.
They may also be heat treated to increase their hardness. One
series 400 stainless steel that may be used is grade 431, which has
the best corrosion resistant properties of the martensitic
steels.
[0067] Alternatively, where even higher corrosion resistance is
desired, a 300 series austenitic stainless steel may be used for
the body. One grade that may be used is 304L stainless steel, which
has excellent corrosion resistance properties.
[0068] The body of a masonry mortar joint finishing tool may be
manufactured to have desired properties. One such manufacturing
method may be casting. Casting the body may provide better
dimensional repeatability as compared with other production forms.
The method of casting used to produce the masonry mortar joint
finishing tool body may be casting. A form of casting is investment
casting (also known as the "lost wax" method of casting), which
provides excellent dimensional repeatability. Other methods may
also be used, such as die-casting or sand casting.
[0069] The body of a masonry mortar joint finishing tool
manufactured by investment casting may be more than fifty percent
harder and two-hundred percent stronger than current bodies cast
from zinc and brass alloys, and malleable iron.
[0070] In another embodiment, the body of a masonry mortar joint
finishing tool may be formed by forging. Forging provides the body
with high directional strength, structural integrity, and
toughness. One method of forging may be the conventional closed die
method. One form of stainless steel used in the forging process may
be powdered stainless steel. Powdered stainless steel may be
pressed into shape at a high pressure, sintered, and then forged.
Other forms of stainless steel may also be used for forging a
body.
[0071] Manufacturing the body by casting or forging may also
provide more durability over other methods. For example, casting or
forging may produce a body that is thicker and thus more wear
resistant and longer lasting than a body formed with sheet metal.
Additionally, a tool with a cast or forged body may be heavier and
thus more sturdy and comfortable to a user, as compared with a body
formed of sheet metal.
[0072] In another embodiment, the body of a masonry mortar joint
finishing tool may be formed of sheet metal stainless steel. This
body may be formed by stamping. Where the body has multiple pieces,
the pieces may be secured to each other by spot welding.
[0073] Once the body of the masonry mortar joint finishing tool has
been formed, it may be polished to a mirror-finish. Methods which
may be applied include using a buffing wheel and a belt with a
polishing compound. Polishing will provide a smooth tool working
surface that minimizes drag when the surface slides against
concrete during operation.
[0074] The foregoing description has been directed to specific
embodiments of this invention. It will be apparent, however, that
other variations and modifications may be made to the described
embodiments, with the attainment of some or all of their
advantages. It will also be appreciated that features described
with respect to one embodiment may be applied to another, whether
explicitly indicated. Therefore, it is the object of the appended
claims to cover all such variations and modifications as come
within the true spirit and scope of the invention.
* * * * *