Fixturing system for woodworking
A device for use with a wood-based structural element having an outer surface and inner surfaces defining a T-slot, wherein the T-slot has a central section that is open at the outer surface, and has a pair of undercut sections projecting from opposite sides of the central section, and the inner surfaces of the structural element include a pair of inner surfaces facing inward, the device comprising: a T-nut having an outer portion receivable in the central section of the T-slot, a screw-threaded bore, and an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion; wherein the bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of about 10 times the cross-sectional area of the bore; and wherein the T-nut is configured for use with a wood-based structural element.
1 . A T-nut device configured to reduce clamping pressures and bending moments imposed on mating T-slots that are machined directly into relatively weak wood-based materials, comprising:
an outer portion including a screw-threaded bore;
an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion;
wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 5 degrees and 30 degrees,
wherein the clamping surfaces are formed of plastic,
wherein the T-nut is configured for use with a wood-based T-slot material, and
wherein the clamping surface angles of inclination are less than or equal to a static friction angle of the plastic clamping surfaces on the wood-based T-slot material.
2 . The T-nut device of claim 1 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 10 degrees and 25 degrees.
3 . The T-nut device of claim 1 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 15 degrees and 20 degrees.
4 . The T-nut device of claim 1 , wherein the screw-threaded bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of at least about 10 times the nominal cross-sectional area of the bore.
5 . The T-nut device of claim 1 , wherein the outer portion further comprises a plurality of unthreaded sockets.
6 . The T-nut device of claim 1 , further comprising anti-rotation pins oriented in the plurality of unthreaded sockets.
7 . A T-nut device configured to reduce clamping pressures and bending moments imposed on mating T-slots that are machined directly into relatively weak wood-based materials, comprising:
an outer portion including a screw-threaded bore and a plurality of unthreaded sockets;
an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion; and
wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 5 degrees and 30 degrees.
8 . The T-nut device of claim 7 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 10 degrees and 25 degrees.
9 . The T-nut device of claim 7 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 15 degrees and 20 degrees.
10 . The T-nut device of claim 7 , wherein the screw-threaded bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of at least about 10 times the nominal cross-sectional area of the bore.
11 . The T-nut device of claim 7 , wherein the clamping surfaces are formed of plastic.
12 . The T-nut device of claim 7 , wherein the T-nut is configured for use with a wood-based T-slot material, and wherein the clamping surface angles of inclination are less than or equal to a static friction angle of the plastic clamping surfaces on the wood-based T-slot material.
13 . A T-nut device configured to reduce clamping pressures and bending moments imposed on mating T-slots that are machined directly into relatively weak wood-based materials, comprising:
an outer portion including a screw-threaded bore;
an inner portion with a pair of clamping surfaces projecting from opposite sides of the outer portion;
wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 5 degrees and 30 degrees,
wherein the clamping surfaces are formed of plastic,
wherein the T-nut is configured for use with a wood-based T-slot material, and
wherein the strength of the plastic clamping surfaces is greater than the strength of the wood-based T-slot material.
14 . The T-nut device of claim 13 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 10 degrees and 25 degrees.
15 . The T-nut device of claim 13 , wherein the clamping surfaces are inclined so as to project inward relative to the outer portion at angles of inclination between 15 degrees and 20 degrees.
16 . The T-nut device of claim 13 , wherein the screw-threaded bore has a nominal cross-sectional area for receiving a threaded fastener, and the clamping surfaces on the T-nut have a combined surface area of at least about 10 times the nominal cross-sectional area of the bore.
17 . The T-nut device of claim 13 , wherein the outer portion further comprises a plurality of unthreaded sockets.
18 . The T-nut device of claim 13 , further comprising anti-rotation pins oriented in the plurality of unthreaded sockets.
19 . The T-nut device of claim 13 , wherein the T-nut is configured for use with a wood-based T-slot material, and wherein the clamping surface angles of inclination are less than or equal to a static friction angle of the plastic clamping surfaces on the wood-based T-slot material.