View Full Version : SB 9 threading dial set screw size?

10-01-2012, 09:38 PM
I just got a threading dial for my SB9 lathe but I don't have the set screw holding the dial on. I am missing the one that goes in the apron, I have the one holding the pin to the dial. Anyone know what size thread this thing is?

10-02-2012, 12:24 AM
mine is 1/4 x 20.I use a brass screw so as not to mark the pin,makeing it hard to get in and out.

10-02-2012, 10:26 AM
My SB9 uses a 5/16x18 set screw.

10-02-2012, 10:28 AM

I have a 40’s area 9” South Bend lathe, on mine the setscrew that holds the pin to the machine is 5/16-18 and the one that holds the Thread Dial to the pin is -20 with a very small square head. I just now changed it to a socket head caps crew, so I do not have go looking for an adjustable wrench.

Jim Connell, DeLand FL.
Daytona Beach is near us.

You haven’t begun learn until to learn until you learn how little you know.

10-02-2012, 12:49 PM
FYI some times I have found on old lathes that the hole was re-tap to a new size. Some of the screws on the 9 and 10K lathes are #12 that are hard to find today and was later re-tap to 1/4 20.

Try this site for information on 9" south bend lathes http://finance.groups.yahoo.com/group/southbendlathe9


10-02-2012, 05:42 PM
1/4 20 is too small.

10-02-2012, 06:26 PM
The screw you noted on the thread dail stud is a 5/16 NC.
I was noting other screws on the lathe was #12 (.216 dia) was FYI only


1/4 20 is too small.

Errol Groff
10-02-2012, 06:46 PM
Measure the ID of the hole and go to your Starrett (or other) drill chart and find what thead size matches your thread hole.