The Stefan video is very informative. Notice a few key elements:
- brass shim stock washer material = relatively soft compared to mild steel & particularly anything approaching spring steel shim stock if that was ever the goal
- 0.2mm thick (= less that 0.008") so again easier to shear than maybe what you are trying?
- pins are HSS & dowel pin = very hard. I'd guess 62-65 Rockwell C. This ties in with what I was suggesting about heat treating is very likely a pre-requisite
- block was D2 tool steel. This is an air hardening tool steel, although I believe he said he did not harden. In its annealed state, still pretty tough stuff. He mentioned nice bore & relief (not taper) which I think has more to do with parts fall-through clearance.
Even with this relatively thin/weak/small material you could hear the 'thwunk' as the pin sheared through. It makes me cringe a bit seeing his mill spindle in this manner bearings wise, but anyway. So reflecting on your project, hopefully you can see the differences. More cutting area, stronger, thicker stock, softer shearing tools & a different recipe of clearances involved.