Tapping 2-56 holes in thick Ti

REK Knives

REK Knives

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Hey guys, normally I don't have any issues tapping 2-56 holes in ti, however, I've snapped 4 taps (at least) over the past few days on this integral folder I'm working on... The problem is that it's about .384" thick. I've even oversized the drilled holes to #47 bits to no avail. I also read where some people have better success going fast with a cordless drill, but that didn't work either. So far I've been doing it by hand and going slow. Any tips or ideas?
 
Why do you have to tap the entire thickness? Can't you drill a clearance hole for at least half the thickness? Tapmatics save a lot of broken taps.
 
Alan Davis Knives said:
Why do you have to tap the entire thickness? Can't you drill a clearance hole for at least half the thickness? Tapmatics save a lot of broken taps.
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Because it's an integral folder (spyderco nirvana) so to have the clip positioned the same position on the other side requires through holes, and they need to be threaded all the way through so the clip can be set up for right hand or left hand carry.

I've got to look into one of those tapmatics for sure!
 
You didn't mention what you're using for cutting fluid, but I really like Anchor Lube when tapping Ti and stainless.

~Chip
 
razor-edge-knives said:
Because it's an integral folder (spyderco nirvana) so to have the clip positioned the same position on the other side requires through holes, and they need to be threaded all the way through so the clip can be set up for right hand or left hand carry.

I've got to look into one of those tapmatics for sure!
Click to expand...

Tapmatic with good fluid, in & out about 20 times or more. I like CRC cutting oil. Also I would tap from both sides, rather than all the way through. Then you will not need to tap as deep.
 
Since its very thick would it be acceptable to tap from from both sides? that would reduce the depth the tap has to penetrate. Not ideal, but it would probably work
 
Nebulae said:
Since its very thick would it be acceptable to tap from from both sides? that would reduce the depth the tap has to penetrate. Not ideal, but it would probably work
Click to expand...


You have no way of aligning the thread pitch up so both sides match.
 
I use a hand tapper to keep the tap axial to the hole. Lube is good as is frequent reversing. The neat thing about about breaking a tap in Titanium is you can dissolve the broken tap with acid.
 
Any chance you got ahold of some bottoming taps ? Are you sure they are starting taps ?
Sharp ? Just because they are new may not mean they are well made.

You might look at the better industrial taps which tend to be "Spiral Point".
 
Use a hand tapper, good lube, and a sharp tap. Shine light directly on the tap, and watch the flutes. You'll see them begin to twist as torque increases. As soon as that tap begins to twist just a little, back it off to clear the chip. Patience!
 
if using full length screws clearance all but the center 1/8 inch and be done. 1/8 inch of thread will hold any pocket clip you have
dont full around with all this tap from both sides stuff cause thats just a good way to mess things up
 
WValtakis said:
You didn't mention what you're using for cutting fluid, but I really like Anchor Lube when tapping Ti and stainless.

~Chip
Click to expand...

Thanks Chip, I'm using Tap Magic cutting fluid

Alan Davis Knives said:
Tapmatic with good fluid, in & out about 20 times or more. I like CRC cutting oil. Also I would tap from both sides, rather than all the way through. Then you will not need to tap as deep.
Click to expand...

This is a good point, however, I was wanting the thread pitch to match up because on one side it got wallowed out a little bit on one hole so the threads for the first 1/16" are non-existant.

Frank Niro said:
Could it be the taps you are using are too short?
Frank
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Good thought Frank, but I don't think so, I checked this and they are snapping before ever reaching the top of the tapping threads.

12345678910 said:
What kind of taps ?

Show me

Tapmatics keep it straight.
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I've mostly been trying the general purpose 2-56 taps for through hole threading from Mcmaster Carr. But recently I tried one or two plain old carbon steel thread repairing starting taps. The method I use is to drill the hole on the drill press, then put the tap in the chuck and take the belt off of the pulley so I can manually spin the chuck from the top. Then, since the Ti is clamped down I use one hand to lower the chuck by using the lever and the other to spin the pulley which spins the chuck, very slowly. This ensures that the hole I drilled and the tapping hole are lined up. I go slowly and back it out every little bit. It just seems to reach a point that it won't go any further and snaps.

Wowbagger said:
Any chance you got ahold of some bottoming taps ? Are you sure they are starting taps ?
Sharp ? Just because they are new may not mean they are well made.

You might look at the better industrial taps which tend to be "Spiral Point".
Click to expand...

I've tried starting and through hole. They are from Mcmaster which I have had great success with in the past as far as quality but others may know better.

butcher_block said:
if using full length screws clearance all but the center 1/8 inch and be done. 1/8 inch of thread will hold any pocket clip you have
dont full around with all this tap from both sides stuff cause thats just a good way to mess things up
Click to expand...

I may end up doing this, but I will have to drill and install helicoil inserts for the 2-56 thread pattern. Hope I can avoid it though.
 
Looks like Mcmaster has taps specifically designed for titanium, part # 2401A24, but they are $50 each for a 2-56 tap! Anyone tried these or know if they work?
 
I use thread forming taps on Ti, you will need to follow the manufacturers chart as far as bit size goes. Thread forming is much stronger on Ti. Moly-Dee works great as tapping fluid on Ti. I need to find my link... on new computer right now.
 
general purpose 2-56 taps for through hole threading from Mcmaster Carr. But recently I tried one or two plain old carbon steel thread repairing starting taps.
Click to expand...



Those descriptions are kind of meaningless to me.

Show me a photo of the tap..
 
Daniel Fairly Knives said:
I use thread forming taps on Ti, you will need to follow the manufacturers chart as far as bit size goes. Thread forming is much stronger on Ti. Moly-Dee works great as tapping fluid on Ti. I need to find my link... on new computer right now.
Click to expand...

I'm no expert... but Daniel's method works for me. Thread-forming tap into a 5/64" hole with Moly-Dee... in a Tapmatic. I can't remember the last time I broke a 2-56 tap... though, admittedly, I don't tap nearly as many holes as Daniel. I also don't tap 0.384" thick, so YMMV.
Erin
 
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