Snapped m10 bolt removal help?

[littlecookie]

Hi I was putting my step back on Renault traffic van when one of the 4 bolts snapped off inside the threads there's about 8mm of the bolt stuck also it's about 2mm below surface, bought the new 35mm m10 bolts from bq as old bolts where too rusty but new bolt snapped like a twig, what's the best way to remove if possible
cheers

 

[Burnerman]

The only thing you can really do is to drill the old bolt out, really......this means centre punching the snapped off stud as accurately as you can, and then drilling the core out a bit at a time, using new drill bits.
When you are close to the 10mm diameter, have a threading tap standing by to recut the thread.
I'm a bit confused about why a new bolt should snap so readily?
Personally I don't rate most screw extractors - others will no doubt disagree!
Would there be any possibility of drilling right through and fixing a nut on the other end?
John

 

[Belle427]

If your going to try screw extractors then try this type, they are the only ones ive ever had any success with.
http://www.ffx.co.uk/tools/product/Dormer DORSETA 7320760112045 M101 CSCT Screw Extractor Set A

 

[Nozzle]

Flood it with plus gas first of all before using any type of screw extractor - if the screw extractor breaks off you'll really regret it. They so hard it then makes drilling the fitting out impossible.

One the fitting has started to budge you should loosen tighten loosen tighten increasingly more which grinds the rust into finer powder and stops the thread getting caught up.

Nozzle

 

[empip]

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[JohnD]

I like to heat up the screw first, this breaks down the grip of rust. Woodscrews you can do with a man-size soldering iron, but metal conducts away the heat so a small flame is better.

Empip's left-handed drill method is great, it will often wind out the screw, with the help of heat and vibration to loosen it. If not you can drill it out.

 

[empip]

http://www.cncexpo.com/MetricBoltTorque.aspx

Careful not to overtighten, 28 ft/lb for a lubricated M10 bolt.

Place socket on bolt head, apply 28 lbs of force at 12 inches from bolt centre that should do the trick.

Check out the force required, perhaps on bathroom scales - not a lot is it ?

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[Burnerman]

I'm still surprised the bolt didn't strip its threads before snapping off......just on occasion a metric fine thread is used in some instances rather than the usual metric coarse.....try finding one of them in your odds and ends box
The magic solution for shifting any stubborn bolts is the gas axe of course - if the situation allows - and the hotter the better.
John