Quick tapping question

Chiro75

Chiro75

Joined
Feb 4, 1999
Messages
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Here we go again! One thing I can't seem to get clear about tapping... let's say I'm using a 1-72 tap in titanium. I drill my #whatever hole (I have all my folder supplies at home) and I'm in 0.09" 6/4 Ti. The procedure for tapping is like "twist two turns, then back it out to break the chips free..." When they say to back it out, does that mean back it out like a 1/4 turn or does that mean back the tap all the way out, clean the chips out, then start again? I assume it's the former, but I don't know...
 
I would say all the way out. It's better to be safe than sorry when tapping. If you're not tapping a lot of holes at one time then its not worth breaking a tap trying to save time. I started off working on knives by tapping holes on my dad's knives and have tapped a few thousand holes in my life so far and nothing is worse than hearing a tap break.

Chris J. Smith
 
Maybe I don't understand how a tap works/is constructed, but if you back the tap all the way out, then in a couple turns, then all the way out again, etc, is it still going to keep lining up properly in the threads that have been made already? Like, let's say the cut starts at 12:00. If I back it out, clean the chip off, then start tapping again, if the tap starts at 3:00 instead of 12:00, don't I have a major problem on my hands? Or does a tap sort of self-align? That's what's always confused me.
 
Just break the chip Chiro.Dont get locked into the 1/4 turn thing either.You can feel resistance when its time to back up and break the chip.Very tiny taps like that can break without warning so just go slow,heck your only going thru .030 to .100 of material so even if you go 1/8 turn and break the chip its not going to take long.As far as the chips go keep your air gun close by and when you back the tap up to break the chip give her a shot of air to blow the crap out of your hole.Dont forget to use some type of lube!
 
when i used to work at a sign company we had a tapper attached to the drill press. Made easy work out of some thick stuff! Lube that sucker for sure. Hell, spit on it ;)
 
Chiro75 said:
Maybe I don't understand how a tap works/is constructed, but if you back the tap all the way out, then in a couple turns, then all the way out again, etc, is it still going to keep lining up properly in the threads that have been made already? Like, let's say the cut starts at 12:00. If I back it out, clean the chip off, then start tapping again, if the tap starts at 3:00 instead of 12:00, don't I have a major problem on my hands? Or does a tap sort of self-align? That's what's always confused me.
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The tap should go back in smooth, little resistance until it starts cutting again. As long as your not pushing down on it hard you shouldn't have a problem with it .

The way that I look at it is if you're only going to be tapping three or four holes be safe and try not to break a tap because I'm guessing that you don't have a multitude of taps just lying around.

I personally use a cordless drill to tap holes. It makes quick work of tapping, just get into a rythm and keep a loose grip on the liner so if the tap binds it will just take the liner out of your hand.

Chris J. Smith
 
For knife work, where the tap goes all the way thru the metal, always use a spiral point tap. The spiral point drives the chips ahead of the point.

The reason taps break is usually because with a regular tap, the chips must climb up the flutes to get out. ;)
 
Always use lube when cutting threads and make sure you have one recommended for Ti. You reverse the tap only enough to break the chip.Only in a deep hole should you occasionally remove the tap completely and clean off the tap.
 
LOL at myself because I don't follow much of the advice that has been given here. I use 0.050 in my liner lock and most screws are 0-80. I normally don't "feel" the need to reverse the tap on the small holes. I also don't use any lube. Out of all the folders, autos, and prtotypes I have made I have only broke two taps. And one of those was from dropping it on the cement floor while still in the T-Handle.

But I think the advice given here is good and should be followed. You will get the feel for it. I think the hardest part of tapping is getting the hole started straight. I use the tapered taps which help out a bit getting things perpendicular. There is nothing that will bust a $7 tap quicker than going in crooked. Oh, well, except for dropping it. ;)
 
Put the tap in your drill press and get it started by hand. That will keep it straight. Just make sure you have a hole under the steel so the tap doesnt bottom out on the drill table.
 
Steve use a variable speed drill with reverse
go straight , don't bend the tap going in and out.

you can brake a tap with chips all broke up in there too. auto tappers don't have to be backed out like that, so yopu don't either.

you'll get the feel for it. if hand taping just don't let it bind to much
you'll feel it, you also feel it bind backout out at times, you'll get used to those puppy's.. but use a variable speed drill.. it's what I use.. zip zip it's done.. :)
 
NICE THING ABOUT Ti. IS IF THE TAP BREAKES JUST SOAK IT IN CIRCUT BOARD ETCH OVERNIGHT THE TAP WILL DESOLVE!
 
Good to know, guys, thanks! When I broke my other tap I was trying to take it through 1/8" thick steel of some unknown type without backing it out. Dumb, right!? Anyway, on MSC's website I ordered tapered taps, I think. They weren't spiral flutes, so I probably got the wrong thing.
 
I back it out all the way every once in a while to clean out the hole. The key to tapping by hand is patience, patience, and more patience. Just when you think you can go a 'little further' with out backing up, the tap breaks. (At least for me it does.)

I can't believe some of you guys use a drill :) ...although the tip to start the hole with the tap chucked into a drill press is a good idea i'll have to try next time.
 
jiminy said:
I back it out all the way every once in a while to clean out the hole. The key to tapping by hand is patience, patience, and more patience. Just when you think you can go a 'little further' with out backing up, the tap breaks. (At least for me it does.)

I can't believe some of you guys use a drill :) ...although the tip to start the hole with the tap chucked into a drill press is a good idea i'll have to try next time.
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The key to tapping holes with a cordless drill is to use a drill that has a good brake. As long as when you let off of the trigger the tap stops you should never have a problem. I timed myself a few times and I think I was doing about 150-200 holes in ten minutes. I would dunk the tap in Tap-Free about every 4th hole and keep trucking.

Chris J. Smith
 
Chiro75 said:
Good to know, guys, thanks! When I broke my other tap I was trying to take it through 1/8" thick steel of some unknown type without backing it out. Dumb, right!? Anyway, on MSC's website I ordered tapered taps, I think. They weren't spiral flutes, so I probably got the wrong thing.
Click to expand...

Wrong on both counts. You need SPIRAL POINT, not spiral flutes.
 
The type and brand of tap are important. Plug is much better than bottoming. Greenfield two flute work the best for me. I'm tapping 15N-20 steel as well as some Ti. I use a cordless or my preferred is a tapping head. I only go forward until I have the hole tapped then I remove the tap. This is a forming tap practice not like you learned im metal shop...Take Care...Ed
 
I've been using a cordless drill tapping 0-80 and 1-72 in titanium for at lest 8 or 9 years. I used to break taps doing it by hand but never with the drill. I know it doesn't make since but it works, and I use a big dewalt 14.4 volt.
Another thing that will help a lot, I use a 1/16'' hole for 1-72 tap.

Don Hanson lll sunfishforge.com
 
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