Evening, gents.
Can anyone suggest a supplier for left hand drill bits? I'm drilling sheared-off bolts out of old motorcycles on a fairly regular basis, and if I could get some LH bits there's always the chance that the blasted things will come out on their own.
It has to be said that the usual "heat it up" technique works pretty well, but the designers are buggers for putting blind bolts near rubber seals...
Tracey tools always used to offer a selection, probably worth a try.
Cheers Tim
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
Why not drill in the normal manor and then use a stud extractor, these are normally LHT. I guess it depends on the dia of sheared bolt.
One method I have used with success is to use a mig welder to build up metal on the end of the sheared bolt and then welded another bolt head on.
When close to oil seals, small buildup and then allow to cool before repeating. Use of the anti splatter spay helps stop metal sticking to the surrounding areas as well.
Adrian
They are. And they are a complete *bastard* when they shear off. Please don't ask me how I know that...
The other problem is that they tend to "spread" the sheared-off stud, making it grip even tighter.
I hate the bloody things.
I'm too cack-handed with a MIG to do that reliably enough. I must practice.
In article , Tim Leech writes
Cheers Tim, there's nothing listed on their website, but I'll give them a ring in the morning.
In article , Wilf Baker writes
These screws tend to be well seized (steel screws, ally cases and years of road salt...). They also tend to be small-ish sizes (4, 5, 6mm) I'd be very worried about snapping the tap to be honest.
Hi Nigel, There are some listed on the Tracy tool site on the clearance page at
In article , John Kneeshaw writes
Ahah! So they do. I'd missed those.
Many thanks John, I've ordered a couple of sets.
Cheers
If any other steel bits are out of the way then use 5 molar (1/2N) or less Nitric acid to dissolve the steel screw out of the aluminium hole. It will have no effect on the ally other than improving any anodising but will quickly remove the screws.
Mark Rand RTFM
Craps! If I only new about the Nitric acid bit myself I would have kept hold of the 2.5 litres of the stuff we had at work. It cost the company quite a bit to get it collected and disposed off. Nitric Acid 75%. It was
10 years old.And I bet someone here would have had a use for the 2 Kg of Mercury as well.
Adrian
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