I pinched a Os 21 RG, Orion Wasp 12, and a Os.12 CVR. I'm assuming they need to be broken in again, is this true? I am a machinist and made the tools myself, they all turned out pretty tight.
Rex

If they're really tight, you should break them in again.

Yes, definitely! The few engines I've had pinched the TDC was so tight that I had to loosen the glow plug to keep it running the first tank or two ... then better than new as far as performance goes!