Daniel Grass - posted 16:42, Wednesday 23 October 2024 - last comment - 09:39, Thursday 24 October 2024(11928)
Broken Tap in First Hole of 10" CF Flange
While CNC machining a 1/4-20 breadboard pattern into a 2nd 10" CF flange, the tap broke going into the first hole in the middle of the part. It did two "peck taps" into this hole and then broke while tapping near the bottom of it, I think on the way down. I am not sure why it broke; maybe Paul Stovall (the head of the MCE shop) will know when he is in tomorrow.
There are a few paths forward: scrap the part or tap the rest of the holes. The best case senario is that we can remove the tap and fix the hole. If the hole isn't salvagable, I can drill it out and tap it with something like a 5/16-18 or 5/16-24 hole. We could also proceed with one hole that is useless.
Another life achievement unlocked! Welcome to the world of machining SS. I hope your expert machinists will help with one of these solutions, or one of their own tricks. https://www.practicalmachinist.com/6-effective-ways-to-remove-broken-taps/
If this will be in vacuum, it is not a good idea to leave it. If it is in air, perhaps grinding it down to below the surface level is sufficient.