I know there are places i could have bought these. but i like to tinker,so tried my luck to make my own.
THIS WILL ONLY WORK ON SHIMS LESS THAN .004...
I took an cheap 1/4" socket and drill out where the nut goes with a 21/64 drill bit , then grounded down the outside to a tapper end..
when i need a shim i put this sharp end on a shim stock sheet and twist it around like a cookie cutter. do this with a soft piece like a tire on the back side of the sheet...then cut out the outside edge shape like the cap.

I found out it worked better to use this home made tool like a cookie cutter rather than hammer it on a block of wood.. also making the hole first is better too...
IF you try this you may find a better way ,this was just tinking around ,and it works ok for me..
GOOD LUCK TO YOU

36 nut, I bet you have a unique way of cutting
the holes in donuts before you roast them on a stick! Ha! Ha! good show!

(He probably has ever one of that pile of frogskins he started out with too!)

And good luck, your self....Carson!

I use a similar process to punch holes in gasket material when I make new gaskets. With this method you can make just about any size hole, from 1/4" up to nearly 1/2". Just take a steel golf club shaft (free at any pro shop or garbage can at your local course!) and cut with a hack saw or plumbers tubing cutter. Then use a small round file or Dremel tool with a rotary bit and taper the inside diameter to a sharp edge. Use the cutter in a cookie cutter fashion to cut holes. Thicker material can also be cut by tapping on the unsharpened end. A bolt fit in the unsharpened end can be used as a striking head.
I've made a set of 3 or 4 for common hole sizes. The golf shaft steel holds a good edge and is easy to resharpen.

Or...Why not just spend less than $5 to buy a 9 piece set of gasket hole punches, harbor Freight has a set on sale as we chatter....

That's just too easy!

not only that, Macky, but you get to keep those 5 frog skins!!!!!!

Dan.

Yes, then if you live here in Texas With the fiver you can go to a Quick-Stop and buy either a couple gallons of gasoline or a pack of cigarettes and a cold beer! ..... OH, I almost forgot a lottery ticket with five chances at the big jackpot!

On the other hand where did I put that Harbor
Freight sales catalog?

Now, if you used mertric sockets to make the punch forms, the planet would be better off without them!