SB compound question
Some of you may have seen this question posted elsewhere. I was told the experts are over here, hence:
I'm working on retrofitting a South Bend milling attachment to a lathe of European design. It seems that South Bend aprons have two set screws (usually they stick out with square heads) each 45 degrees off axis from the crossfeed screw axis. Those screws push on beveled pins which bear on a male circular dovetail on the bottom of the compound rest. Or milling attachment, or whatever else is mounted directly on the apron.
My question is about the beveled pins themselves. Did South Bend thread the holes they move in all the way and have the pins be slightly smaller than the minor diameter of the threads? Or is the part where the pins slide bored to a smaller diameter than the part where the set screw threads? Or what?
This particularly applies to a 14" South Bend lathe but I'm guessing they made them all conceptually the same but just sized differently. In fact, I would greatly appreciate the actual dimensions of the pins and screws on a 14" South Bend, thanks!
On my 9" lathe the pins are larger then the minor diam. and move in a bored out hole.
Coupla corrections: it isn't the apron I'm interested in, it's the cross-slide (saddle?). Also, SB calls the pins "shoes". Really need dimensions if you have a 14-1/2" South Bend lathe.
I don't understand why it matters. It is not as if the cone knows the difference between a 1/4 and a 5/16 shoe. As long as it is soft, has the right angle on the end, and travels closely in its bore, any shoe will do.
I want to clarify what I need. I need dimensions for parts no. 42 and 43 from this drawing: http://tinyurl.com/9ksvtm6 sized for a 14-1/2" lathe.
I have a 14 1/2" cross slide with shoes and screws sitting on the bench right now. The shoes are .484" in diameter and 1 3/8" long. The working surface is a 1 1/4" radius cut at a 30 degree angle. The set screws are 9/16"-12 x 1". The holes in the slide are .485 thru and tapped about 1 1/4" deep.