But when I go to start the job I’ve hit the clamps twice now an am nervous about actually running a program using them. Before this, I would just screw the wood down to the wasteboard, but I’d love to work with clamps instead. I had the clamps setup front and back, but maybe the trick is having them off to the sides (X)?
I would only use a clamp that tall where I absolutely had to, I have some of those but use them on table saw jigs.
I bought this kit of handy bits;
That kit is in modern units but I believe you can get them in Imperial naval and farming units too
And then made some simple flat plywood clamps that only stuck up 10mm from the top of the workpiece and if I did run a toolpath or rapid into them they’d just get cut rather than breaking the cutter. It’s somewhat visible that most of those clamps have been involved in some sort of accident since they were made.
They’re long enough to reach from the T track and keep the metal clamp bolt well away from the toolpath. I still set my retract to 10mm for everything to give clearance when I accidentaly rapid over the top of a clamp in a toolpath though.
I use cam clamps. They are 3/4 inch high and that keeps them low enough that I can use a low retract height saving time when the Shapeoko is making rapid movements. The clamps I see above work well but dust collection can still hit them.
I have them in two sizes big and small. I mostly use the large ones. There is a countersunk hole in the cam clamp that is exactly 1/2 inch from the bottom. Because I have a 2 inch spacing on my spoilboard it uses the same size 1/4-20 bolts until I surface my spoil board enough I go from 1.5 to 1.25 inch bolts. The clamps are made of oak with the grain running the length of the clamp for strength. If they get cut up I just replace them. I also have an L bracket I use a lot to position square to the router.
I have a 1/4 inch ratchet with a 7/16 inch 6 sided socket on the bench dedicated to each of my machines. I have never had a project come loose. You hold the clamp tight and tighten it up. Sometimes I have to tighten up one clamp and the project moves a little, I just tighten up another clamp and go back and readjust the original clamp to keep the project square and in the L bracket.
The clamp design came from Myers Woodshop. They were free or you can buy them from etsy.com from Myers Woodshop. There are a lot of different types of clamps but I have had no problem with the cam type clamps. If the project is too far from the clamps I just put a piece of scrap wood to make up the difference. I have a drawer full of scraps that I use depending on the project.