You're a machinist, that doesn't know how to make a shim?
I'm sorry, that does not compute. Could you explain how you got to be a "machinist" and never made a custom shim?
"Machine operator" maybe?
I make a stack of shim stock.
Clamp them between two flat pieces and drill a hole in the center
Mount the stack on an arbor, with the clamp pieces and do the outside diameter. you want to finalize the final diameter with a file or sandpaper as to not fold over the edge
Mount the stack in your custom jig that holds the stack in alignment by the outside diameter
Now do the inside diameter. Again finish the diameter in a way that doesn't fold over the edge, I use a ream.
The "trick" is to keep the stack compressed at ALL times so they stay aligned, and the more pressure you use the less likely it is the edges will fold over.
You will end up tossing the outside pieces of the stack as you can't keep them compressed, so if you want one shim you have to make five
When you're done go over the shims with a stone
...I'm not a machinist, I'm a hack that owns machine tools.
... but I know how to make shims... a VERY simple/basic necessity for a machinist... or a hack with machine tools.
MACHINISTS make shims all the time, it would be one of the first things you did as an apprentice... and, as a "machinist", HOW do you setups without making shims? At least half of my setups involve shims. (If you're a CNC jockey and someone else does your setups, you're a machine operator. I don't care what your employer's title for you is).