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Gilmer clutch torque testing tool, and a lathe rest question

Posted: Tue Mar 19, 2013 11:50 am
by Cavediver
I've looked at the various ideas for testing the clutch in my '56 Shopsmith, and have settled on a drilled-out 5/8" nut and set screw.

What size set screw should I use?

I'd reference existing attachments, but I don't have any... My $100 Shopsmith only has the headstock, tubes and legs, main table, lathe end, and jointer. No attachments :(

ETA: Oops. After rechecking mickyd's posts on the subject, I realized I missed the spec: 5/16-18

Also, for a stock '56, which type of lathe tool rest do I need? I've seen several that appear to be threaded pipes, and some that look like they have a row of teeth (rack?) up one side of the pipe.

Posted: Tue Mar 19, 2013 1:03 pm
by terrydowning
The original tool rest looks like a threaded pipe and the tool rest arm is permanently fixed to it. The newer tool rest has the rack of teeth. the tool rest arm mounts to the top of that and swivels and locks by means of a set screw.

Either one will fit your '56. I have one of each. The newer design locks better than the older design but you do have to be a bit of a gorilla on the set screws. I just got a set of these (parts 296 and 296a and they made a huge difference in tightening everything down.

Posted: Tue Mar 19, 2013 1:13 pm
by Cavediver
terrydowning wrote:The original tool rest looks like a threaded pipe and the tool rest arm is permanently fixed to it. The newer tool rest has the rack of teeth. the tool rest arm mounts to the top of that and swivels and locks by means of a set screw.

Either one will fit your '56. I have one of each. The newer design locks better than the older design but you do have to be a bit of a gorilla on the set screws. I just got a set of these (parts 296 and 296a and they made a huge difference in tightening everything down.
Thanks for clearing that up. I'm keeping an eye out for lathe, drill press, and disc sanding components; it's good to know both will work with a preference for the newer style.

Also, are those parts replacements for the setscrew, or L-shaped wrenches that allow for a better grip?

Posted: Tue Mar 19, 2013 1:18 pm
by terrydowning
Yup. the 510 + tool rest is the same as the 500.

Posted: Tue Mar 19, 2013 1:24 pm
by Cavediver
terrydowning wrote:Yup. the 510 + tool rest is the same as the 500.
Got it. Thanks!

Posted: Fri Sep 13, 2013 2:15 pm
by michaelosburn
My carriage is a Mark V 500 series & the tool rest that came with it has the threaded tube. I tried to install it and it just drops down through the hole without engaging the teeth on the lift gear. The guy I bought it from said he never used the lathe. The lift gears work fine with the table.

Posted: Fri Sep 13, 2013 2:35 pm
by billmayo
The tool post along with the carriage and SPT legs are 1 1/4" OD. I am sure there are other sizes for other machines that might have gotten included.

Posted: Fri Sep 13, 2013 7:07 pm
by JPG
michaelosburn wrote:My carriage is a Mark V 500 series & the tool rest that came with it has the threaded tube. I tried to install it and it just drops down through the hole without engaging the teeth on the lift gear. The guy I bought it from said he never used the lathe. The lift gears work fine with the table.
That just doesn't make sense. An 'original' should fit either carriage(albeit a bit short for a 505/510/520).

FWIW, a 505/510/520 tool rest bracket is NOT the same as a 500(tis 'longer' and has two mounting post holes).

Posted: Fri Sep 13, 2013 7:34 pm
by billmayo
Cavediver wrote:I've looked at the various ideas for testing the clutch in my '56 Shopsmith, and have settled on a drilled-out 5/8" nut and set screw.
That should work. Years ago, I split a similar nut at the set screw when testing and the clutch plates and disks were frozen. I disassemble each clutch without testing now. I use a cut off splined end of a bent Gilmer quill shaft with a 1/2" 15mm socket driven on to the splines. I wrap the clutch teeth in a leather belt and tighten in a vise. I look for between 10 to 15 ft. pd. of torque for the slipage. I recondition the plates and disks along with adding an extra plate to the clutch assembly and have washers I put on the side of the spring to get the torque needed. I have extra Gilmer clutch plates and disks along with rebuild clutches available. Email me if interested.

If anyone is willing to cover the shipping cost, I would be happy to mail a cutoff Gilmer spline shaft to them as I still have a few bent ones that is not in the spline area. I have a metal cutting bandsaw so it is not a problem to cut.

Posted: Fri Sep 13, 2013 8:02 pm
by JPG
billmayo wrote: . . .
If anyone is willing to cover the shipping cost, I would be happy to mail a cutoff Gilmer spline shaft to them as I still have a few bent ones that is not in the spline area. I have a metal cutting bandsaw so it is not a problem to cut.

E-mail sent!