OTish: a silly bit of metrication

I managed to find a local supplier who had 12mm bits this morning. The crazy thing is that he *didn't* have any 13mm, everyone else I spoke to had 13mm and nothing else near. I could only get standard length, so had to contrive an extension for the 'extra inch'

Got about 70 of the holes drilled, counterbored & bolted up today, the rest have to be drilled from below, so they can wait for tomorrow

One of the side benefits of having machining facilities is that I can now make decent one-off counterbores for this sort of thing, in this case about 38mm OD with a 12mm pilot, a piece of old EN8 prop shaft turned up, milled with 3 flutes and ground up on the T&C grinder. Many moons ago, when we were doing this sort of work regularly, I made them up by welding silver steel 'wings' on to a round bar stem which doubled as a pilot, then ground the cutting edges freehand. They did work, but not as well as the new high-tech model !

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

Think of it as getting a square foot free of charge :))

Ken.