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brainbug007
20th July 2012, 03:32 PM
So I tried to take the exhaust off my bike at the weekend to respray it with some VHT paint as it was starting to rust. Unfortunately the bolts used to hold it on where mega cheap/weak and one of them has snapped off in the head which is aluminium :( I tried drilling it out without much sucess as my hss bit just don't seem to really want to drill into the bolt. Seems to just make a small circular pit in the bolt and not really go any further. Any suggestions as to where I'm going wrong? Also if I take it to a dealer how much are they likely to charge to fix it??

robo
20th July 2012, 05:32 PM
This method has never failed me from a small bolt in an ali casting to a monster in some farm equipment.

A small 8mm bolt sheared off in an old srap head just to play with.

http://i1116.photobucket.com/albums/k577/mypickys/000_0090.jpg

Clean up the head of the stud as best you can and place a large washer over the stud but make sure the hole in the washer is no bigger than the stud . Then grab the mig ,up the amps and turn down the wire feed and get a good burn onto the stud and washer

http://i1116.photobucket.com/albums/k577/mypickys/000_0092.jpg

Then get a large nut with say a 10 or 12 mm hole in and weld through the middle onto the washer.

http://i1116.photobucket.com/albums/k577/mypickys/000_0093.jpg

Then unscrew the little blighter.

http://i1116.photobucket.com/albums/k577/mypickys/000_0094.jpg

Da DAAAAAAAA

This will never fail , just take you time and make sure all is clean. I think the heat from the welding is the reason they come out so easy this way. dont forget to disconnect the battery if welding on the vehicle.

Edit. it took longer to type all this than to do the job.

Bob

Talonmotorsport
20th July 2012, 05:34 PM
All though drills used on steel are called HSS (high speed steel) they need to be run at a lower speeds rather than flat out and used with a cutting paste/oil such as ct90. A problem that you may now have is as the bolt gets heated by the head and now the drill bit it may have become hardened which will make the job nigh on impossible to drill in to.

brainbug007
20th July 2012, 08:34 PM
Bob you're the man! That method looks like the way to go :) I was looking at bolt extractor kits etc thinking i was gonna have to spend a good whack of the hard earned to get the bugger out!

alga
20th July 2012, 09:54 PM
Yep, welding is my favourite way to remove stuck bolts, too! Nice trick with the washer!

robo
21st July 2012, 08:17 AM
Bob you're the man! That method looks like the way to go :) I was looking at bolt extractor kits etc thinking i was gonna have to spend a good whack of the hard earned to get the bugger out!

Brainbug if this is the first attempt at this it might be a idea to practice on a couple of old bolts and washers in a vice just to get the mig wire and amps set right, Also get someone to keep the washer firmly in place with a screwdriver because the mig wire on first strike can push the washer off line. Best of luck.

Bob

brainbug007
21st July 2012, 04:16 PM
Cheers mate good idea to practice a bit first :)

The V8 Files
21st July 2012, 10:55 PM
Cheers Bob, will have make a note of this and try to remember it when I next get a bolt stuck :)