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View Full Version : How do I remove a sheared off tap/dye?



Kiwi Graham
23rd September 2008, 19:55
I was re-cutting a thread in an exhaust collector and the tap/dye sheared of inside the thread. :Oops: :crybaby: Its hard as... and a drill bit wont touch it. Anybody out there with a clue what I can doto remove it or somewhere I can take it for someone who knows what to do??

Jeees stuff like this happening realy pisses you off eh! :mad:

quallman1234
23rd September 2008, 20:19
Any of it still poking out the top?
Pilers?

Can you get in from the other end?

hospitalfood
23rd September 2008, 20:29
thats a tough one. is the shear rough ? its unlikely but you may be able to turn it with something ?
failing that im sure that it can be drilled but it would be slow and you need serious gear.
if there is a small amount of tap ? or thread holding it ? hit it very hard with a punch and bash the whole thing out and re-tap a larger size ?
weld/glue a rod on to the tap if the thread is big enough to do that and you have enough space ?

use a rifle, i have one that would do the job.

hope this helps

98tls
23rd September 2008, 20:37
If its not to far down how about a dremel with cut-off wheel to make a groove then unscrew it.

Kiwi Graham
23rd September 2008, 20:40
Any of it still poking out the top?
Pilers?

Can you get in from the other end?


thats a tough one. is the shear rough ? its unlikely but you may be able to turn it with something ?
failing that im sure that it can be drilled but it would be slow and you need serious gear.
if there is a small amount of tap ? or thread holding it ? hit it very hard with a punch and bash the whole thing out and re-tap a larger size ?
weld/glue a rod on to the tap if the thread is big enough to do that and you have enough space ?

use a rifle, i have one that would do the job.

hope this helps

Its snaped of below the surface of a blind (dead end) thread. I've tried drifting it (undoing) it with a punch but no luck. I'm wondering if a super tuff titanium type drill bit (if such a thing exsists) drilled real slow will do the trick. The problem I have is that its on the bike but access is to it is good.

Jerry74
23rd September 2008, 20:44
Bugger tap and die or get an easy out bit

98tls
23rd September 2008, 20:49
If all else fails then Carbide burrs are the answer,use it in a dremel and grind it away,the small ones are cheap as chips on Ebay.Type in Carbide PCB.

98tls
23rd September 2008, 20:52
Fwiw...............http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=350100973892&fromMakeTrack=true&ssPageName=VIP:Watchlink:middle:uk

Dan Mapp
23rd September 2008, 21:03
An old trick that has worked for me in the past is to get the key that comes with tinned sardines, Cut the end off it so it is open ended, push the two progs down the fluttes then just back it out. Good Luck you will need it.
Cheers Dan

Ixion
23rd September 2008, 21:07
You can get diamond tipped burrs to use in a Dremel. It'll be slow slow slow though. If the stub is loose (unlikely, I know), make a tool like the 'sardine key' thing , a couple of screws (or concrete nails) inserted into holes drilled in a bolt head or such, so as to engage the flutes.

Spark erosion will remove it, but not too practical while it's on the bike.

How far down is it? Can you just leave it there and weld a nut on the top of the hole to use instead of the trheaded hole?

BBzz
23rd September 2008, 21:08
Bummer it’s a process it WILL come out. Try Pliers. You my be able to use a centre punch to knock it around.
Is there enough to be able to weld to? use a low hydgen rod (56S) all you need is weld the rod to the tap, Is the collector Alloy or mild steel? If steel try some heat and take it easy.
If the broken tap is @ the edge of the exhaust collector you may be able to cut it out re weld it and re tap it
Mace Engineering in CHCH have a trick arc /spark eroder I think that’s what its called that can remove a broken stud from a block thers probley other companys around as well here Mace web address http://www.mace-eng.co.nz/engineering.html all the best hope this helps.Ps check out the http://www.pivotalengine.com/ part of Mace

Ocean1
23rd September 2008, 21:17
In this order:

Smack it around a bit with a hammer and pin punch, (expect to fuck several) to see if you can loosen it up. If so try needle-nosed pliers to unscrew it. Take some time here ‘cause it don’t get any easier from here on. Sometimes if you get lucky the tap will split lengthways and you can jiggle the bits out separately.

Remove the battery and any sensitive electronics. Get a stick welder, attach the earth close to the area in question. Insert rod in handpiece and stomp it carefully but firmly onto the middle of the tap, do not strike the usual arc. Leave it there until the tap is cherry red. The tap is now "soft", like only a tad harder than the surrounding material. Make with 98tls's trick, concentrate on the tap's centre web and try not to fuck the original thread too much. If you think you can keep a stelite drill on-centre that’s also now an option.

Remove the complete assembly and take it to someone with an EDS spark eroder. Pay them a bunch of money and collect it the next day. If you’re really keen you can make a quick and dirty one but I’m pickin’ you won’t be that keen if it comes to this bit.

Finally, track down and destroy any carbon steel taps you own. Also any blunt or otherwise dodgy ones. This is one area where quality, while no guarantee of success, pays dividends.

Luck dude.

no-coast-punk
24th September 2008, 03:44
This is what I use:

http://www.waltontools.com/products/extractr.htm

Kiwi Graham
24th September 2008, 06:23
Thanks for all the hints and tips guys, I'll give them all a go this weekend......might have calmed down a bit by then :argh:

I like the sardine cand key idea, Ive got an old pair of needle nose pliers, I'll try grinding them down a bit as well.

The collector is mild steal so I'll heat it up a bit to... I assume the collector will expand faster than the tap?

Thanks again for your help.

fLaThEaD FreD
24th September 2008, 06:37
Thanks for all the hints and tips guys, I'll give them all a go this weekend......might have calmed down a bit by then :argh:

I like the sardine cand key idea, Ive got an old pair of needle nose pliers, I'll try grinding them down a bit as well.

The collector is mild steal so I'll heat it up a bit to... I assume the collector will expand faster than the tap?

Thanks again for your help.

Take it to a specialist who does spark erosion. Neat ,tidy and no damage caused.:niceone:

Wired1
25th September 2008, 20:54
Well I guess it's too late to say 1 turn forward, half a turn back now isn't it? Forget the drills and easy-outs and some of the more ridiculous suggestions - you may as well use dilithium crystals. The trick now is to loosen it up slightly and get the long nose or needle nose pliers into the flutes and back it out. You can sometimes break them out but going with the flow - ie unscrewing it is the easiest method. You will never drill it out so don't even try.