Sigh, practicing a skill I would rather not need

[Howard LewisParticipant @howardlewis46836]

Once, I was told that many Taps fail in bending,

So wherever possible use the Tap in a tapping fixture, in a drill chuck in the mill or lathe (Only under power if you are very brave ), supported by a spring loaded support, such as a "Tap Tru", or in guide, held against the workpiece.

If in doubt, the hole can be a tiny bit oversize, (It only decreases the % engagement slightly ) and use plenty of lubricant, and back off frequently to break the swarf into small pieces. Withdrawing frequently to clear the sly can be time well spent..

Lubricant,? Trefolex, Rocol RTD or even bacon fat.

With the tap supported, an suitably sized tap Wrench should allow you to feel how much torque is being applied. If the tap can be felt "springing" it is time to back off a little, clear the swarf, relubricate and try again, more gently.

For the lathe, I made a Tailstock sliding tap holder, similar to a Tailstock sliding Die holder, using ER collets, to hold and support the tap, whilst allowing it to follow the drilling, without any side forces..

HTH

Howard

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