Tapping Titanium

RARanney

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I was looking at some old threads about breaking taps in Titanium. For a 2-56 tap the "chart" recommends a #50 drill. Should I go a size or so larger in Titanium than I would in steel? Thanks.
 
I'd test it in a scrap first. and see what happens

The size that they usualy recomend is for 75% thread(any more doesn't increase strength, it just makes it harder to tap.) a larger hole would make it easier to tap but you loose strength. a lot of machining opperations call for 60% or even 50% thread because it good enough and faster. (cheeper)

I think you should play with it and see if you like it
 
I use a #48 drill for a 2-56 2H tap in 1/8" thick titanium.

Titanium has the tendency to squeeze in between the threads while tapping, so you're really won't go oversize by too much using this size drill.

Go slow, and use cutting lubricant! ;)
 
Hmmm, I just use a #50 drill bit and tap 2/56 holes in .090 ti with no problems at all. Probably tapped 40-50 holes before the tap broke. Are you using an electric screwdriver to turn the tap?
 
I broke a couple while hand turning on a $50 drill press (using Tapmatic fluid), which surprised me since I thought I had it down (nothing like getting cocky to humble oneself). That's when I remembered something about Titanium squeezing in. I think I'll try starting on the press with a #48 or 49 and then finish with the battery screwdriver. Is there a preferred brand of screwdriver? Thanks to all for your help.
 
Ask me!! Ask me!! :D The mostestest important thing I learnt from all the kind folks that helped me in my time of trouble (eg those earlier threads(pun intended)) was to clean out the tap frequently...during the course of tapping 0.050" ti I back the tap completely out twice for a clean before the hole is tapped. Less than twice will still see a snappo for me (tapping M2)...that little speck of ti that you wouldn't think will hurt anything will still be able to lock things up. Sure, there's all the other things to worry about also but keeping it clean should help... :)
 
The BEST battery drill for doing this is the Skill...perfect torque (thanks KIT!! :) :) ) You should use an oversized drill...just a little..... .072" for 2-56.... I dont ever worry about cleaning off the tap but I have also learned not to tap anything over about .100" Larger than that I backdrill the hole with the clearance drill for a 2-56 (.085") Titanium is SUPER strong...you really dont need many threads to hold anything. If you want to tap all the way thru something over .125" do NOT try to power all the way thru...about 1/3 of the way at a time... AND USE SOME LUBE>>>> the kind is not nearly as important as the fact that you use it. The paragraph above is based on EXPERIENCE......I have broken a BUNCH of taps in .156" and thicker ti.......a few in .125" :(
 
:D
For many holes I have found a roll tap works better in titanium.
This forms the thread in the hole making a far stronger thread.
I use tap heavy for this process.
I drill about .002 over .

The roll taps I use are direct from BALAX.
They invented the roll tap!
I use steam oxide coating NOT TI COATED.
They last about 1000 holes before breaking in .15 thick ti!
 
Talk about first rate advice at one's fingertips. Thank you gentlemen.
 
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