Thread: Left-handed drill bits

On the subject of quenching, proceed with caution, just remember that this snapped bolt is in an exhaust manifold, typically cast iron and that doesn't like heating and quenching at all.
A good tactic can also be the application of crc or wd40 to a warm, (not red hot!), component, as it will definitely penetrate better.
The best success I have had with such situations has always been using the welding methods described earlier.

You could try some of this to help things along.
Welcome to: Loctite® Freeze & Release

BTW you did snap it trying to undo it? I think everyone is assuming that.

Stuart

Originally Posted by Stustoys

You could try some of this to help things along.
Welcome to: Loctite® Freeze & Release

BTW you did snap it trying to undo it? I think everyone is assuming that.

Stuart

Hi Stuart. I mentioned using Freeze & Release in my original thread, and yes I snapped it trying to undo the bolt. Not trying to be sarcastic but is there any other way to snap it, unless it's in tension from a compinent hanging of it I suppose.

I'm still unsure about using heat or cold? Everyone mentions using heat but then there's products like Freeze & Release. I suppose they both work the same, i.e. thermal shock and then using a penetrating oil of some sort.

The main problem I can see with using heat,is trying to contain most of the heat to the Bolt and transferring to rapidly to the other part.
Did the bolt start to move at all when you were trying to undo it.
You said you didnt have much room to work with,could you give a bit more area size.

Originally Posted by TheOtherLeft

Hi Stuart. I mentioned using Freeze & Release in my original thread,

Omg sorry I would have read that when you first posted but I've obviously forgotten.

Originally Posted by TheOtherLeft

]
and yes I snapped it trying to undo the bolt. Not trying to be sarcastic but is there any other way to snap it, unless it's in tension from a compinent hanging of it I suppose.
.

Sure, doing it up or maybe even doing it up when you thought you were undoing it.

Originally Posted by TheOtherLeft

I'm still unsure about using heat or cold? Everyone mentions using heat but then there's products like Freeze & Release. I suppose they both work the same, i.e. thermal shock and then using a penetrating oil of some sort.

I've only ever used the spray once. I was very impressed, it worked amazingly well(on a MT3 drill chuck). Its certainly easier to use than heat, not exactly cheap though.

Stuart

Originally Posted by rogerbaker

However you remove the offending bolt, when you have finished coat all of the bolts with Never-Seez or similar heat resistant lubricant. I havent had a seized or broken bolt since I started using never-seez 40 years ago.

Roger

On ya Rog. Good to hear from you.

Dave

Hello T.O.L.,
I assume that there is some space beyond the end of the bolt so if you drill the bolt out as accurately as you can to the minor Dia. and then grind a fine tooth hacksaw blade down so that you can cut through the remaining threads in two opposite places you should be able to collapse the bolt and pick out some of the threads with a scriber and then use a tap to remove the remaining threads if necessary. A very slow process but it has worked for me. Good luck.
Russell

Originally Posted by TheOtherLeft

Not trying to be sarcastic but is there any other way to snap it, unless it's in tension from a compinent hanging of it I suppose.
.

As Stuart said you can snap the bolt off tightening it up , if this happens then an ezyout is the go , unless you have bottomed the bolt. Otherwise ezyouts for small bolts are fraught with danger.
For a 5-7mm bolt that has seized before you do anything else build a dam around the bolt with plastercine, fill it up with penatrine or wd 40 and leave for 24 hours, with a small punch give the centre on the bolt ( dont damage the threads in the block ) a solid belt every couple of hours . This helps the penatrant get down into the threads.

Another method for small bolts like yours is to drill a 2.5mm hole through a block of wood and relieve the end of the hole to 5mm . clamp it directly over the bolt and use it as a guide for a 2.5mm welding rod. It welds onto the end of the bolt , switch off welder and remove the gun , leaving the welding rod welded to the end of the bolt. remove the wood. Repeat the soaking with penatrant and allow the bolt to cool, the welding rod gives a heat shock to the bolt but the heat also expands the bolt so you need to cool it down. Grip the rod as close as possable to the bolt with vice grips and gently remove

I had a small rusty bolt snap off in a downward facing direction under the front sill of my car. I ended up drilling it out and the new bolt went in fine, I must have got the hole just the right size and centred well enough for the old thread to fall out (with some WD40). I drilled a 2mm hole in the centre first using a cheap imitation 'Dremel' tool then drilled the larger hole with a cordless drill. Had to jack the side of the car right up.

Thanks for the tips so far gents.

My plan is to heat up the area using a blowtorch - butane as I don't have an oxy or LPG torch, then when it's still hot spray some RP7 and let it soak for a while. I may do this a few times just to be sure. Then I'm going to belt it with a hammer and pin punch and then drill it out using some left-handed drill bits. When I get close to the original diamater I'll try and collapse the remaining bolt material or even jam an allen key in there and try to unwind it.

If need be I'll just retap it. It's not a critical component as it's only holding the heatshield to the exhaust manifold and the bolts been broken for a few years. it's certainly not something I want to pay a professional for but will treat it as a learning experience.