Tapping or retapping

flattop1

Dawg 89
I don't have thread chasers PD recommend them vs a tap .
So my steering stabalizer bolt came out hard and did not want to go back in .
When tapping or retapping when do you stop if it starts to get hard too turn?
Surely everyone has gone just too far at least once , or have never tapped a hole .
Three tries with added oil and cleaning I stopped the bolt went in .
Still there were some instances I was a bit concerned . It didn't seem like it had been tapped full depth too start with .
2 hrs to find the tap do the job and clean up thats a win !
Well except the mess from looking for the tap set.. ;)
 
When it doesn't want to turn that's when I think it's trying to cut a new thread. I really love the bolts on 1st gen durango's trans crossmember. I call them cutter bolts because the first few threads look like a tap and everytime they come out and go in it's getting more and more messed up. Of course the threaded part is welded into the crossmember and they are a pain to try and chase.
 
I've found if a tap gets hard to turn it's either dull or the metal your trying to tap is kryptonite. Usually a indication your about to break the tap off inside your part. That's were the fun begins.
 
When it starts to get hard to turn, turn it back out, clean the hole and the tap out with compressed air and put in a drop or two of oil. Slow and easy is much better then a broken tap.
 
Not all taps are created equal. You have to start with a tap that is meant to cut threads in. Some taps (usually low grade) are only meant to chase a thread. You should also use a proper tap wrench that allows you to apply equal pressure on both sides of the handle. If you're using an adjustable wrench and only apply pressure from one side you will increase the chance of breaking the tap.
 
Technique I have . My tap set i feel is good . Its not harbour freight . It was a cast part .
I ran into the same situation with a freinds rear shock mount . Metric bolt , original installation . Tap and died both bolt and hole then everything went good but the taping was tedious .
Maybe it is the tap , but some thread rolled out with the bolt so , itend to think it was damaged .
The feel before the catastrophe ; is what i was getting at . You can see the tap flex , feel or intuition ..
 
Yep

Get out the carbide burr on the die grinder, and remove the only tap ever broken in such an endeavor.

Lmao

Turning back and forth further work hardens the tap, making breakage a inevitable outcome.

Machine tappers usually do not stop, and break the chip.

Oil is not the correct tapping compound.
Depending on the material, there are various correct fluids which will maximize tool life.
 
Technique I have . My tap set i feel is good . Its not harbour freight . It was a cast part .
I ran into the same situation with a freinds rear shock mount . Metric bolt , original installation . Tap and died both bolt and hole then everything went good but the taping was tedious .
Maybe it is the tap , but some thread rolled out with the bolt so , itend to think it was damaged .
The feel before the catastrophe ; is what i was getting at . You can see the tap flex , feel or intuition ..
I've been in the situation I think you're describing also on a cast part. Very frustrating! I have the conspiracy theory that the female thread is not actually the same pitch as the male thread. Not necessarily cross threaded but more likely cut wrong at the factory in which it was originally made. The material is soft enough for a 1 time install but that's it. I'm assuming you used the bolt you removed to verify pitch and chose the tap to use. When you start the tapping process it seems to gum up or bind the tap. If you're dealing with a size at least 1/4" or larger I would not let the tap flex. I hate to have any size flex at all. For me it's a feel scenario to know when to stop. Then the choice is to say the heck with it and if it breaks so be it and try it again or I'll look to grind the tap back to where there is no lead and make sure the leading edge of the tap is extremely sharp and it will cut in threads. This comes with risk as well as you may run out of material and end up with a loose fitting connection.

And yes, I've broke a few taps in my life. Most of the time at work and had an EDM available to burn out the center of the tap and save the part.
 
Yes this tap kit came with thread pitch gauges .
With the advent of metrics they have proved quite handy .
 
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