Metal drill bits and drilling out snapped exhaust bolts ...

[Flyingpony]

Tried to extract some exhaust bolts but unfortunately I snapped two before finding out how to get them out without breaking. Who'd have guessed hitting them with a hammer would loosen them up, I simply took out Mr Handi Dandi Pipe Wrench and put some muscle into it since spraying WD40/CRC it didn't help.

So, I then dived into my drill bit collection and picked up a non-concrete drill bit of the right size.

Put it on the bolt and went for it. Unfortunately, the drill bit turned a shade of blue in under a minute and made so much noise I needed to wear ear muffs!

Not sure what's gone wrong, during metal classes at school, those non-concrete drill bits just ate the metal like breakfast and mine barely made a dent.

So did I grab a wood drill bit instead and if so, how can I tell the difference between that and a metal one?

Or are snapped exhaust bolts just difficult to drill out?

I'm not concerned about damaging the thread, I just what them out.

[Dafe]

Perhaps sharp drill bits would have helped, maybe you were running your drill speed too high. But by the sounds of it, you should have used some CDT cutting/cooling fluid/spray. When the bit turns blue or smokes, Stop!
Even consider using another drill bit at this point.

A masonry bit used to drill out a metal body??? Sounds gash!
Masonry bits are blunt! How could they possibly drill into metal? Carbide tips maybe strong enough.

A wood bit? Absolutely no point demolishing a wood bit, stick to a metal bit.

What size bolt did you break? If the thread pitch is over 5mm, you could probably try an impact driver or a screw extractor bit. Screw Extractors are cheap and available from most hardware shops. All you need to do is pilot out the centre of the bolt and try drilling in the extractor bit, when reversing the extractor - pray the rest of the bolt follows. (Drill slowly with heaps of torque).
Consider re-tapping too.

http://www.motorcycle.com/mo/mcnuts/stuckscrews.html

[dhunt]

Tried to extract some exhaust bolts but unfortunately I snapped two before finding out how to get them out without breaking. Who'd have guessed hitting them with a hammer would loosen them up, I simply took out Mr Handi Dandi Pipe Wrench and put some muscle into it since spraying WD40/CRC it didn't help.

So, I then dived into my drill bit collection and picked up a non-concrete drill bit of the right size.

Put it on the bolt and went for it. Unfortunately, the drill bit turned a shade of blue in under a minute and made so much noise I needed to wear ear muffs!

Not sure what's gone wrong, during metal classes at school, those non-concrete drill bits just ate the metal like breakfast and mine barely made a dent.

So did I grab a wood drill bit instead and if so, how can I tell the difference between that and a metal one?

Or are snapped exhaust bolts just difficult to drill out?

I'm not concerned about damaging the thread, I just what them out.

Most drill bits work for both. If it says high speed steel on the case it should be fine. Make sure you are keeping plenty of pressure on the drill as it will just blunten the tip and not really cut other wise. Also you probably should cool the bit if it's getting that hot, water works pretty good or cutting fluid if you have that.

Different metals are softer /harder so take varying amounts of time to drill holes.

Is your bit still looking fairly sharp?

[twinkle]

I saw someone trying to drill through mild steel using a masonry drill bit with the drill in reverse once

[Firefight]

...an "easy out" thingy

should work ok


F/F

[Dafe]

I saw someone trying to drill through mild steel using a masonry drill bit with the drill in reverse once

Sounds like the time I got caught trying to solder some Skyhawk electronic components with lockwire.

[kickingzebra]

Yeah, if the bit is blued, you might as well biff it in the rubbish, or at least sharpen it back to below the blued portion.
Slow, sure and stedfast when drilling metal.
Cobalt bits retain their sharpness a bit longer than High speed steel. HSS will do the job, but yeah, lower rpms/cutting lubricant and or cooling spray.

Those easy out things sound the bizzo, never seen them though?! must look into those!

[Firefight]

Those easy out things sound the bizzo, never seen them though?! must look into those!

here you go

http://www.toolprice.com/category/sc...squareeasyout/ - 32k

a pic here, most good tool supplier or engineering supply should have some.


F/F

[Ixion]

Just one point - if you have the misfortune to snap an Ezi-out in a hole, you are humungeously rooted. About the only thing that will get that broken bit out is spark erosion (unless there's enough proud to weld or braze something onto it)

[Motu]

Exhaust studs undergo a little bit of heat treatment and can become quite hard.Good sharp drill and cutting fluid is the way as mentioned.

A very good method is a left hand drill bit in a reversing drill - often the broken bolt or stud will just wind out.I have some extractors that drill a left hand hole,then wind in an extractor,which then extracts the bolt - all in one tool,about the best you can get.

[Flyingpony]

Perhaps sharp drill bits would have helped, maybe you were running your drill speed too high.

What size bolt did you break?

Broke two typical Japanese 10 or 12mm exhaust bolts.
I've got the feeling that finding the drill bit at the bottom of hand-me-down tool box means it's not sharp and that 2800rpm doesn't qualify as slow.

Make sure you are keeping plenty of pressure on the drill as it will just blunten the tip and not really cut other wise. Also you probably should cool the bit if it's getting that hot, water works pretty good or cutting fluid if you have that.

Most definitely was putting my weight on the drill, had the engine casing on the garage floor held steady between my legs, so applying weight was easy.
Cooling, Hmm, garden hose and an electric drill

Looks like I've more research to do otherwise I'll have to pop into a machine shop and ask them to extract them.

[imdying]

Just one point - if you have the misfortune to snap an Ezi-out in a hole, you are humungeously rooted. About the only thing that will get that broken bit out is spark erosion (unless there's enough proud to weld or braze something onto it)

Yep, Ezi-outs are the devil... hate having to get those damn things out, everyone snaps them off.

A very good method is a left hand drill bit in a reversing drill - often the broken bolt or stud will just wind out.I have some extractors that drill a left hand hole,then wind in an extractor,which then extracts the bolt - all in one tool,about the best you can get.

Oh, now you're just giving away all the good secrets! Left hand twist drill bits in a drill going in reverse is a top method of getting things out. Eventually, it normally just winds the old bolt out

[stanko]

What size bolt did you break? If the thread pitch is over 5mm, you could probably try an impact driver or a screw extractor bit.

If its got 5mm thread pitch then its a 52mm diameter bolt ,wouldnt need too many of those to hold the exhaust on.

its probably a 6mm or 8mm bolt , they normally take a 10mm or 12mm spanner

[jonbuoy]

Go SLOWLY with a sharp drill bit, work up from a small size 2 - 3mm, use CRC as cutting fluid if you don't have any proper stuff. Don't put too much pressure on the drill bit - let the face do the cutting. If you had it in a drill press it would go through it like butter - its hard to keep a drill exactly verticle when your doing it by hand - thats why it takes so much longer.

[Gixxer 4 ever]

With out reading all the posts here. Drill slowly. Very slowly and you will get a good result. Use a good drill bit. Go to your local engineering shop and purchase 1 drill bit for the job. When you purchase the easy out make sure it costs a bit cos the cheap ones will brake off and you will have a very big problem then. You can't drill them out. Take your time and get some good tools for this job. It is worth it or you will end up with a big bill to fix the damage. Heat the broken bolt if you can.
Good luck