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View Full Version : Cutting and punching hard shim stock



PStechPaul
11-03-2014, 05:32 PM
I'm placing an order with McMaster for a shim stock assortment, and it is full hard (Rockwell B90) low carbon steel. It contains one 8" 12" sheet of the following thicknesses: 0.002", 0.003", 0.004", 0.005", 0.007", 0.01", 0.012", 0.015", and 0.02".
http://www.mcmaster.com/#9301k5/=ufsu5l

I was wondering how I might be able to cut it. I don't know if tin snips would work. I thought perhaps a thin abrasive wheel in a Dremel tool could be used, and maybe use double stick tape to secure it to a piece of scrap material while grinding it. It is too thin to saw, but that might work if it were sandwiched between two pieces of 1/8" aluminum or such. Also I might want to drill a hole in it, or perhaps use a punch. I have a hand punch something like this:
http://www.mcmaster.com/#3461a22/=uft3p2

There are also U-shaped shims that I considered. These will be used to tram my milling machine by loosening the bolts of the column to the base and sliding the shim around the bolts. So I could use the following stainless steel 18-8 Rockwell B54. They are 2"x2" and have a 9/16" slot for a 1/2" bolt.:
http://www.mcmaster.com/#97235k816/=uft0pr

boslab
11-03-2014, 07:07 PM
Cuts ok with a snips, guillotine, even scoring and bending on thin stuff, I used to get the bolt shims cut by laser, but the bolts were 30mm, a nibbler works too, but watch the punchings, wear glasses, they are like little crescent razors
Mark

Sun God
11-03-2014, 08:31 PM
If I'm reading that correct, and you're saying it's a 90 on the Rockwell B scale - then that is very, very soft. RB90 is below the lower practical limits of the RC scale.

You could cut thin steel shim at 90 RB with household scissors, or even a scalpel.

EDIT: by way of comparison, that hardness is in the same range as fully annealed 4140.