Cutting Shim Stock

I've got some fancy shapes to cut out of stainless steel shim stock of various thicknesses, some quite thin (.003).

I know that I can cut this stuff with scissors, but when I do I almost always deform the edges of the finished product.

What I would really like to do is stack a bunch of sheets up and drill and bore holes into them as a stack. But I am worried about burs.

How does one cut shim stock so as to maintain its accuracy?

Thanks,

Bill

stack them and EDM them.

Quantity would be nice.

Stan-

EDm is a good idea, but I'd have to send that out. I'm looking at 60-100 pieces.

B

depending on the size, you may be able to get away with using some kind of 'sacrificial stock' (ie some cold-roll steel plate) and make a sandwich with the shim stock in the middle, and go ahead with the drilling....dunno what you can do about the outside profile tho, other than hand cutting....

Yeah, what 77ironhead said. The key is keeping the stack tightly clamped together so it acts like a solid pc. And use sharp tools, too.

if you want to make a habit of this there is a "laser printer" thing

I have a 1953 dodge m-37 that i needed steering preload shims that i made with the sandwich idea and it worked great. the shims had a profiled od and a large center id with 4 bolt hole in between. after clamping i drilled the bolt holes and used them to locate and hold for the center boring head and profiling cuts

link

definitly laser
mark

You might try chemical milling. Put a mask on both sides of your Shim stock and use ferric chloride. I make masks using a laser printer.

Make a punch and die? Stack oversize pieces, put waster plates on each side and machine as a stack. I cut stainless shim up to 0.010" with a paper shear.

Mike K said:

Yeah, what 77ironhead said. The key is keeping the stack tightly clamped together so it acts like a solid pc. And use sharp tools, too.

Click to expand...

That's what I would do.

After cutting them out lay them on a surface plate (not your best inspection plate) and block sand lightly with 320 or so to get rid of burrs one side at a time. When we get laser cut shims in we still have to deburr them that way. We have an old plate just for rough use. We call it the "shop rock".

good pair of properly sharpened snips will cut thin stock with out much of a burr. a hole punch against a hard surface like steel, will punch a hole with out "to much" distortion. Obviously a laser or water jet is the best way.

Billy Boy said:

I've got some fancy shapes to cut out of stainless steel shim stock of various thicknesses, some quite thin (.003).

I know that I can cut this stuff with scissors, but when I do I almost always deform the edges of the finished product.

What I would really like to do is stack a bunch of sheets up and drill and bore holes into them as a stack. But I am worried about burs.

How does one cut shim stock so as to maintain its accuracy?

Thanks,

Bill

Click to expand...

I cut way too much thin stuff for my liking, I have tried several different methods with some success: Rigidax wax - I attach thin stock to a plate with wax. Stacks of multiple sheets are possible, just be sure that the metal pieces are hot so the wax sticks. Sometimes I will mount blocks with the wax as well since it lets me get at 5 of the 6 sides of a block. Melt, wipe, then acetone to clean off the wax. Use moderate feeds so as to not pop the work piece off. I wish the peel strength were greater, sometimes it's necessary to have a thicker top piece to prevent thin stock from curling and popping off. 3M VHB tape - great for holding thin sheets of plastic, even slippery polypropylene. Tricky to get back off, may need an acetone soak, but peels off many materials. Superglue and cardstock - sandwich cardstock between pieces, machine, and use a chisel to pop pieces apart. Doesn't work with very thin material or coolant. Epoxy - Glue together with epoxy, machine, then soak in hot epoxy remover. None of these are ideal, best to keep an eye on your work when trying these out because adhesion isn't super good. Messy and time-consuming, and I'm still looking for better ways, but hopefully this helps.

Cut to rough size, stack and sandwich between 1/4" or so thick aluminum. Clamp tightly together- vise, clamps, drill any holes and put bolts thru. Now mill the profile. Done.

Tape to a piece of pink styrofoam and have them water jet cut. Works Great!