Tap holder design - lathe

[martik777]

Does the square chuck that holds the very end of the tap increase the chance of breaking the tap or would a holder that contained the round shaft (less stickout) result in less torsion? The problem with the latter is slippage but a grub screw on the flats or on a grind would stop that. I'm power tapping 3/8 16 in 416 SS with a chuck but I have to hand tap the last few threads due to slippage so I'm looking for a better holder.

 

[MyLilMule]

That's a good question. I would think yes, you're going to increase your chances of breaking the tap.

If you're not using a spiral flute tap, you should consider it. Not sure how it will do in your specific situation, but they are good for power tapping.

 

[murraym]

Ive always wanted to make some of these, just haven't had the need yet i guess

 

[benmychree]

Sometimes slippage is your friend when tapping, versus breaking the taps.

 

[twhite]

I much prefer slippage. I like just chucking up the tap in the chuck. Then make it tight enough to not slip. If it bottoms out it just spins. I just turn on and off the power and inch it in. I try not to bottom it out. I try to put a sharpie mark as reference.

I do not do this on stainless. Just start enough and hand tap finish.


Cutting oil is my blood.

 

[darkzero]

I've got a Vertex Tap Chuck. It's got jaws to grip the shank & holds the square to drive the tap. It's a rigid holder so no slipping, I rarely use it because of that. I prefer to use a keyed chuck for power tapping, I rather the tap slip then break.

 

[martik777]

Good points about the slippage preventing breakage. When I do a large batch it's a fair amount of extra time to finish off those last few threads.

I wonder if there's a holder with an adjustable clutch type mechanism?

 

[Aukai]

Tapmatic Other Metalworking Equipment for sale | eBay

Get the best deals on Tapmatic Other Metalworking Equipment when you shop the largest online selection at eBay.com. Free shipping on many items | Browse your favorite brands | affordable prices.

www.ebay.com

 

[mattthemuppet2]

You can get torque adjustable tap holders. I have one, just need to give it a clean and try it out

 

[Winegrower]

For power tapping I use a Procunier 2E tapping head. What's comforting is that the tap slips as a function of the downward pressure on the quill...a little slipping, just pull harder. I've never broken a tap, though I suppose it could happen. I only use spiral flute taps for this.