how good is chemical metal?
Discussion
andy-xr said:
Bringing this one back up as I'm in the market for something to avoid having to drill out a broken bolt.
I dont have a welder, and have no plans to borrow on, but I need to remove a snapped M5 bolt from a hole. THere's still enough on the shaft that I can try vice grips (didnt work) and drill a small pilot hole (broke the bit)
I'm now thinking of chemical metal'ling a nut to it and trying to unscrew it. Is the Halfords stuff really going to grip?
you don't stand a chance.... If you have broken a drill bit, or eziout in there it will be almost impossible to remove by drilling. if there is a bit sticking out, try knocking on a small torx bit if you have enough to bite on...I dont have a welder, and have no plans to borrow on, but I need to remove a snapped M5 bolt from a hole. THere's still enough on the shaft that I can try vice grips (didnt work) and drill a small pilot hole (broke the bit)
I'm now thinking of chemical metal'ling a nut to it and trying to unscrew it. Is the Halfords stuff really going to grip?
good luck
buzzer said:
you don't stand a chance.... If you have broken a drill bit, or eziout in there it will be almost impossible to remove by drilling. if there is a bit sticking out, try knocking on a small torx bit if you have enough to bite on...
good luck
Is that the case when using Cobalt drill bits too? I've an Eziout lodged in a hole now...good luck
Back to the OP, I've used JB weld before and am pretty happy with it. It's more been used to fill holes / cracks than stick anything down.
Neil_M said:
Is that the case when using Cobalt drill bits too? I've an Eziout lodged in a hole now...
A cobalt drill won't touch an easi-out, unless it happens to be made from cheese (the easi-out, not the drill...). Decent quality cobalt drills couldn't even drill out one of the exhaust studs on my Fireblade. Admittedly it was the hardest stud I have ever had to deal with, and the cobalt drills happily munched their way into a couple of other exhaust studs on the same bike. I eventually got it out by building up enough weld on the end to bring it above the surface of the cylinder head, and then welded a strip of steel with a hole drilled in it over the top. The stud had only recessed that much as all the nuts I had welded on to remove it kept shearing off!It might be possible to break up the remnants of the easi-out with a decent quality center punch - it's worked for me before with a tap snapped off in a hole I was threading. A quality masonry bit might do the job, but don't count on it, and it will be a slow process. You can buy (expensive)carbide drill bits which will probably do the job, but they are very brittle and really need to be used in a drill press.
Other than that, it's spark erosion time. IME trying to remove a seized/corroded fastener with an easi-out type thread extractor is a recipe for disaster and shouldn't even be attempted. Welding a nut on the end is the best approach if possible, but if not it's better to drill out the fastener and re-thread (with heli-coil or timesert if necessary).
CROMWELL SCREW DRILLS Google this. I have a set of these and they do work. Example. I have drilled a hole through the middle of a broken M10 spiral flute machine tap. However, you need the gear to use these ie workpiece securely clamped,drill bit held tight in chuck or collet, spindle of machine no play or run out.
Having said this although they will piss through an easyout unless you hit the dead centre it will run off into the softer metal so I don't think it will work for the OP. Useful things to have though !
Having said this although they will piss through an easyout unless you hit the dead centre it will run off into the softer metal so I don't think it will work for the OP. Useful things to have though !
Mr2Mike said:
A cobalt drill won't touch an easi-out, unless it happens to be made from cheese (the easi-out, not the drill...). Decent quality cobalt drills couldn't even drill out one of the exhaust studs on my Fireblade. Admittedly it was the hardest stud I have ever had to deal with, and the cobalt drills happily munched their way into a couple of other exhaust studs on the same bike. I eventually got it out by building up enough weld on the end to bring it above the surface of the cylinder head, and then welded a strip of steel with a hole drilled in it over the top. The stud had only recessed that much as all the nuts I had welded on to remove it kept shearing off!
It might be possible to break up the remnants of the easi-out with a decent quality center punch - it's worked for me before with a tap snapped off in a hole I was threading. A quality masonry bit might do the job, but don't count on it, and it will be a slow process. You can buy (expensive)carbide drill bits which will probably do the job, but they are very brittle and really need to be used in a drill press.
Other than that, it's spark erosion time. IME trying to remove a seized/corroded fastener with an easi-out type thread extractor is a recipe for disaster and shouldn't even be attempted. Welding a nut on the end is the best approach if possible, but if not it's better to drill out the fastener and re-thread (with heli-coil or timesert if necessary).
Thanks Mike, I appreciate the reply. I might look at a carbide drill bit to see what they do...It might be possible to break up the remnants of the easi-out with a decent quality center punch - it's worked for me before with a tap snapped off in a hole I was threading. A quality masonry bit might do the job, but don't count on it, and it will be a slow process. You can buy (expensive)carbide drill bits which will probably do the job, but they are very brittle and really need to be used in a drill press.
Other than that, it's spark erosion time. IME trying to remove a seized/corroded fastener with an easi-out type thread extractor is a recipe for disaster and shouldn't even be attempted. Welding a nut on the end is the best approach if possible, but if not it's better to drill out the fastener and re-thread (with heli-coil or timesert if necessary).
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