View Full Version : Cutout in Camlock Stud

11-18-2004, 03:03 PM
Does anyone have the specs for the cutout in the camlock stud on a lathe chuck? It's a D1-4 spindle, but I'm thinking it's the profile that's important, not the specific dimensions. Anyway, my plan is to make a stud long enough to use as a drive for the dog when I'm turning betwee centers. Any ideas on how well that will work?

[This message has been edited by jmcmullan (edited 11-18-2004).]

11-18-2004, 10:49 PM
Good idea but you could just use a clamp on the center--Like the grinding centers. The cutout on the studs are egg-shape, as I'm sure you've noticed. It's probably clearance for the cam. I'm not sure if the stud would stay tight without a stop (chuck).

How about threading an oversize rod and using a standard stud screwed into it? That is countersink, drill and tap. Make sure the rod will "stop" against the head.

[This message has been edited by CCWKen (edited 11-18-2004).]

11-18-2004, 11:55 PM
All that would no doubt work, except my center doesn't protrude out of the spindle adapter far enough to get a clamp on it. It just seems kind of elegant to use the existing camlock to do this. I'm making the "dog-drive" stud out of a 3/4" piece of drill rod turned down to 5/8" for the camlock section. The shoulder is what the cam pulls up tight against. I think I've got the profile of the cutout figured out by measurements, but I thought I'd see if anyone had real specs to check it against. Specifically, I plan to use a 3/4" end mill to cut into the stud at a right angle .125" deep, 9/16" from the shoulder. I'll then rotate the stud 45 degrees and exit (towards the end of the stud) with the mill to create the clearance for the cam. If it all works out I'll post the results.

BTW, does anyone know how to put drawings up on this forum? I've never actually seen any in a posting>

11-19-2004, 12:07 AM
I'm sure I cut some w/ endmill for my faceplate, just a portion of circle. It has always stayed on tight. Not sure that meets exact specs, but it has worked for me.

I'll try to see what size I used.

Agree w/ CCWKen, you will need a shoulder to seat on spindle nose to ensure the cam locks tight!

11-19-2004, 12:45 AM
Yup, looks like 3/4 was my best guess too.

I went straight in 1/4" deep at 5/8 from shoulder.

Was some info at Pratt Adapter website, seems not on studs though. Don't remember.

11-19-2004, 12:46 AM
<font face="Verdana, Arial" size="2">BTW, does anyone know how to put drawings up on this forum? I've never actually seen any in a posting</font>

Click on the link below. It explains how to add images to your post. The image must be on the web NOT your machine. Many use Photobucket to store images.


Here's an example:

Paul Gauthier
11-19-2004, 12:53 PM
After you scan your docs into your computer you can follow these instructions to post them.


Paul G.

11-19-2004, 02:49 PM
That is a neat idea. I'd worry about the single stud damaging the spindle face, and would instead make a complete drive plate / spindle protector ring with three studs. This would look a lot like a ... spare D-4 chuck backplate, so I'd ultimately just find one of those and tap some holes into it for studs to engage the dog tail.


charlie coghill
11-19-2004, 09:39 PM
I agree with toolbert. I would hate to take a chance on damaging the spindle face.

11-20-2004, 12:04 AM
Point well taken re: damaging spindle face. Actually, I'm not too worried about my "dog-drive" stud doing damage. The camlocks are relatively loose tolerance as far as I can tell. But anything flying around in the area of the mating face taper does worry me. After I get through this project - with great care thanks to y'alls warnings - perhaps I'll try something that will guard the spindle face better.

For anyone that's interested, the 9/16" shoulder to center of the initial 3/4" cutout IS too short. I had to cut the shoulder back another 1/16" to get the camlock to engage. So, uute's 5/8" is the correct profile on my spindle.

Turning the stud (on the axis of the initial 1/4" cut into the stud) 45 degrees, then backing the end mill out (away from the shoulder) seems to work well (i.e. provides clearance as the cam is engaging) and looks right when eyeballing it next to one of my chuck studs.

Thanks to all for all the comments.