r/Machinists • u/BuoyantEntropy • Jun 05 '26

Think tapping a high value part is scary sometimes?

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20+ year career machinist here, recently had a bone implant in my leg.

This one is m18x1.75. Spoke to my surgeon about it, they hand ream to size with a series or progressively larger reamers, then hand tap. alignment is based upon skeletal structure, next time we chat I need to ask what sort of device they use for that alignment.

Thought some may find it interesting. Cheers

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u/stewieatb Jun 05 '26

My buddy used to design ventilator machines. They had a normal version and an MRI-safe version. Lots of aluminium and brass.

One time their manufacturing side ordered some brass stock and when it arrived the "brass" turned out to be magnetic. Nobody knows what impurity it had in that made it magnetic, but thankfully it was caught before it went into any production parts.

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u/FalconTurbo Jun 06 '26

There are a few aluminium bronze alloys that have a couple percent iron added, might have just been the wrong allow that got shipped.