cam locks for the mill - do they work?

[Your Old Dog]

Just ran across these and was wondering if they work at all. Seems they would be handy for working on low profile projects.

cdcotools.com has them for $22.00 for 6. Looks like the screw head is eccentric.

[davidh]

got um here... they will hold the work steady but not necessarly tight to the face of the table. they are eccentric and kinda neat.

someone here has a drawing that shows how to make them. i can;t remember who or when it was. oldtimers disease seems to have my tiny brain sometimes.

[ckelloug]

I have a set of mitee bite clamps who was the originator of this design. I just used them yesterday to square a couple of 1/2 thick by 10 inch square plates of a2 tool steel. They are quite effective although their usage is a bit of an art. It took me a while to indicate in the flat side of each plate and get the clamps tight without buggering the indicated position and orientation of the part. Also, they tend to loosen under vibration.

Despite the negatives mentioned above, I love them and have concluded that they are indispensable for working on parts where traditional clamps would get in the way.

Regards,
Cameron

[alanganes]

You may be thinking or the plans posted by Rick Sparber. His website is here:

http://rick.sparber.org/

You can find a bunch of great write-ups on machining topics by clicking on his metalworking link. The one about the cam clamps is here:

http://rick.sparber.org/Articles/tc.pdf

He does a great job explaining explaining how to make stuff. Lots of good info.

[Evan]

I have been using camlock clamps of my own design for a while now. They work well and are pretty easy to make even without CNC.

Here is the pattern I made up. It doesn't have to be entirely accurate, it isn't critical that the cam be a perfect spiral.



This is what they look like from various materials and in use. The black one is steel and is cammed using an angle grinder spanner.

[lazlo]

What Cameron said +1.

I use the Mitee Bites all the time to clamp flat workpieces, but you have to be really anal about locking the T-slot the right distance away from the workpiece so the cam has the right distance to work, or the workpiece will go flying.

Ask me how I know this.

Edit: the hexagonal-shaped cam locks are also great for clamping irregular workpieces, like a casting -- you clamp them all around the perimeter, and the hex will rotate to grab even the strangest shape.

I also bought split cam locks that I haven't had the chance to try yet: they're like a Mitee Bite that's split down the middle, with an O-ring to hold the two halves together. They're used in mold work where you put them in a slot or cavity in the workpiece, or between two molds, and the cam spreads the two halves of the hex apart, clamping the work.

[PaulT]

I've got a set of both the "real" Mitee ones and the CDCO set. They both work pretty well, as mentioned above they're a little futzy to get set up right so it takes a little playing around with them to learn how to use them, when I first got them I was in "WTF?" mode for a while until I figured out how you are supposed to use them.

I use them for skim cuts on big plates to flatten them for fixture use and they're good for that. If you use them right they actually do put some downforce on the plate when clamping.

I can see they would also be useful in fixtures, but I haven't used them like that yet.

The CDCO parts are above average for chinese tooling, not perfect of course, they had some brown yuck probably leftover from the plating process stuck in the t-nut threads that was a pain to get out, but once that was gone they're actually pretty nice. The real Mitee Bite ones are a little nicer and have brass hex parts (the clamp) versus the steel CDCO ones, so I use the brass ones on parts I don't want nicks on.

Definitely a nice thing to have if you do any work with plate sized workpieces.

Paul T.