Broken tap
Whats the best way to remove a broken tap?
Not that I broke a tap off in a reciever or any other part of a gun.[?]
I'm asking for a friend who's too ashamed to admit that he broke a tap off in a reciever.
I'd never brake a tap in a gun.[8D][8D]
Realy, I'm mad as all get out.[:(!] What is the best way to get it out?
Born To Hunt... Forced To Work... #@!#$!!
Not that I broke a tap off in a reciever or any other part of a gun.[?]
I'm asking for a friend who's too ashamed to admit that he broke a tap off in a reciever.
I'd never brake a tap in a gun.[8D][8D]
Realy, I'm mad as all get out.[:(!] What is the best way to get it out?
Born To Hunt... Forced To Work... #@!#$!!
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In a former question on a broken tap, the answer was to use a type of acid that would dissolve the tap without harming the metal that was tapped. How is this possible? Chemists please answer. 0 -
As you"ve found out taps are brittle. But this can work to your advantage when one does break. Usually you can cause it to shatter by placing a good quality hardened punch against the broken off section in the hole and giving a good sharp rap with your hammer.The shattered bits can be picked out, just be careful to not damage the interior of the hole.
Good luck0 -
Years back when I still was working in machine shops, there was a special tool known as a Electro Discharge Machine, "EDM". Carbon or copper electrodes were used to remove metal by generating a electric arc.
To remove the broken tap a electrode would be machined smaller in diameter then the tap. The electrode would then be used to remove the center portion of the tap. After this was done, hopefully the outer portions of the tap could be removed without damaging the receiver.0 -
DS I tried the punch and was able to shatter the large portion towards the top but still have the tip down low. Any ideas? Starting to buger up the threads to. I think I can save them but not sure how this is going to end up. I'll try some more tomorrow.
Ruff the dilly mob bopper is kind a like the police. Never around when ya need them.[8D]
Born To Hunt... Forced To Work... #@!#$!!0 -
How deep is your tap, size of hole?? May have to work with your punch again. May try an "easy-out" be careful though, you may end up breaking that as well, then your in REAL deep do-do. 0 -
The only way to reliably remove a broken tap without buggering up the threads is to have it EDM'd out.
Take it to a machine shop. If they don't have the equipment, they can tell you who has.0 -
brownell's also has carbide three flute drills that will drill out a broken tap. 0 -
quote:Originally posted by MIKE WISKEY
brownell's also has carbide three flute drills that will drill out a broken tap.
Using a small diameter carbide drill, without the proper equipment and tooling,i.e. receiver secured in a heavy vise, bolted to the bed of a drill press, with the drill exactly concentric with the broken off tap, is a recipe for disaster.0 -
Ginmaster: Several people have said "burn it out" ie EDM. In reality they are right. Since you are talking about a receiver, and you don't mention thread size or hole diameter, if it's less than .090, (90 thou) you may just be screwed, since the threads are starting to get messed up. The problem with drilling is the bit wants to travel, which would cause more damage to the threads. Not knowing the area of the receiver and how much wall thickness you have to play with is tough. They don't make thread inserts for real tiny holes, so if you lose the threads compelely,you would have to find a metal shop that could put enough weld deposite in the hole redrill and tap. Then you might have to reheat treat depending on location. For a shop to set that up to try and burn it out you are prbably looking at $50-$75. If other work is required such as the welding I mentioned, that's even more. You may just want to start looking for a replacement receiver. One last thing, going to an oversixe thread, is always a possibilty if you have the wall thickness. But then finding a replacement screw with they same size head as the original could be a problem. You may have to turn the head of the screw down. If you go this method, get a hand full of screws done, that way you will have replacements on hand in case you mess the slot up. Regards Dave
One other method that does have "some" success is acid! A weak acid solution put directly on the tap, a drop or two at a time. I don't recommend you do this, but a larger machine shop might know of this method and use it. So you would have to call around. Regards Dave0 -
Couple ways that have worked for me.
Butt..... patience is king.
1. Soak with penetrating oil, dry, then use a light oil. Remove any chips via blowing out.
Ready a probe like a dental pick that will fit in a flute, a hole or crack.
Heat area around hole. Can use a heat absorbing paste, and or make a metal shield like folded foil, or heat cloth to protect hole area.
Using the probe try to turn out, or work back and forth.
Sometimes two probes help.
Can also try to cool down the tap via small rods that fit the hole, and kept in the freezer. Anything that helps enlarge & shrink increases removal.
2. Using an Automatic Center punch, just keep punching-hitting the tap. Center punch tip is usually hardened, and can be ground down to fit hole, which also helps protect the threads.
3. Using a small abrasive grinder tip, grind flat the tap, so you can drill out, or hit-shatter. It makes a flat surface if drilling out using a LEFT hand drill bit.
4. If a larger hole is going to be done, then using the proper size drill for the new hole, drill into the existing hole as far as possible. Then try #1, or #2 above. #3 can cause damage to area needed to be threaded so don't use.
BEFORE trying to remove the tap, check the threads, and if necessary, using a Blind Tap, or simply make one....chase the threads available making removal upwards easier.
USE a drill with machine vise, vertical mil, etc for stability.
Happy Bullet Holes!0 -
This doesn't help you now but I never use any 4 flute hand tap - for anything. They are just to weak. A three flute gun tap, or 3 flute bottoming tap.
The suggestion of breaking the tap off is the best way. I think you'll be surprised what an EDM machine goes for, per hour.
You never have said what size screw you were working with, and if it is small consider using a TIG tungsten for a center punch, but wear those safety glasses as when it breaks you never know where those little pieces go.
Your mileage may vary.
"If you ain't got pictures, I wasn't there."0
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