metman
Materials
- Feb 18, 2002
- 1,187
Recently we purchased a used one with a 10" X 12" work surface. I am the lucky one who got to use it first with the pleasure of cleaning/stoneing to look and function nearly new.
It included a separate piece of steel 3/8 X 3/4 with a .739 dia hardened cylinder attached at one end and a .375 dia hole in the other end with a center distance of 10" between cylinder and hole (same center distance as the angle plate itself). We figured out that the extra piece was for setting-up compound angles by attaching it to one of 2 holes on the horizontal work surface or one of the 2 holes at at the back vertical surface. These holes are also .375 dia with a 1/4-20 thread at the bottom of each of the 4 holes.
It seems logical that a standard shoulder screw could be used to attach the compound angle bar (CAB) to the angle plate except that a standard 3/8 shoulder screw has 5/16-18 threads rather than 1/4-20. We can use a 1/4-20 SHCS and buy or make a 3/8 O.D. X 1/4 I.D. bushing to align the .375 dia holes in the CAB and angle plate. Or we could drill out the 1/4-20 threads 4 places in the angle plate and tap for 5/16-18 so that a standard 3/8 shoulder screw can be used.
1) Anybody have an idea why Bridgeport did not tap for
5/16-18?
2) Is there such a thing as an off-the-shelf 3/8 dia shoulder screw with a 1/4-20 thread?
3) We could make a 3/8 dia shoulder screw with 1/4-20
threads.
4) Is there some other way to attach & align the CAB that were are overlooking? This seems very curious!
Jesus is THE life,
Leonard
It included a separate piece of steel 3/8 X 3/4 with a .739 dia hardened cylinder attached at one end and a .375 dia hole in the other end with a center distance of 10" between cylinder and hole (same center distance as the angle plate itself). We figured out that the extra piece was for setting-up compound angles by attaching it to one of 2 holes on the horizontal work surface or one of the 2 holes at at the back vertical surface. These holes are also .375 dia with a 1/4-20 thread at the bottom of each of the 4 holes.
It seems logical that a standard shoulder screw could be used to attach the compound angle bar (CAB) to the angle plate except that a standard 3/8 shoulder screw has 5/16-18 threads rather than 1/4-20. We can use a 1/4-20 SHCS and buy or make a 3/8 O.D. X 1/4 I.D. bushing to align the .375 dia holes in the CAB and angle plate. Or we could drill out the 1/4-20 threads 4 places in the angle plate and tap for 5/16-18 so that a standard 3/8 shoulder screw can be used.
1) Anybody have an idea why Bridgeport did not tap for
5/16-18?
2) Is there such a thing as an off-the-shelf 3/8 dia shoulder screw with a 1/4-20 thread?
3) We could make a 3/8 dia shoulder screw with 1/4-20
threads.
4) Is there some other way to attach & align the CAB that were are overlooking? This seems very curious!
Jesus is THE life,
Leonard