Using a screw extractor

PeteW

Hiya, I have a screw that snapped off in a door handle that I need to remove.

I bought a set of screw extractors and managed to drill a hole in the screw, insert the extractor and give it a turn or two, but then it gets stuck and I can't work out how to turn it enough to get the screw out.

The screw extractor looks like this:


Except the one I am using is only 3 or 4mm at the top end. Any ideas what tool I should use to turn it some more? I tried an adjustable wrench but it couldn't get a good enough grip and was just spinning off. I also tried a power drill on reverse setting, but that wouldn't grip either.

I thought maybe a socket, but I can't find one that is small enough. Most socket sets only go down to 5mm which is too big.

Help!

Thanks

Pete

hartcjhart

you need a 'tap' wrench there are 2 styles

1)
http://cgi.ebay.co.uk/eclipse-tap-wrench_W0QQitemZ220541581003QQcmdZViewItemQQptZLH_DefaultDomain_3?hash=item33594d76cb

2)
http://cgi.ebay.co.uk/Number-1-5-Tap-Wrench-For-use-with-hand-taps-1-12mm_W0QQitemZ260436398013QQcmdZViewItemQQptZUK_Home_Garden_PowerTools_SM?hash=item3ca3380fbd

roger196

If you know anybody into old cars or model engineering, they should have a tap wrench they could lend you.

Dov_2

We have this problem at work all the time, however on a much larger scale with sheared bolts in metal. The best thing you could use is a pair of Visegrips or Molegrips like these http://cgi.ebay.co.uk/Visegrip-Curved-Jaw-Locking-Plier-7in-Vise-Grip_W0QQitemZ130347108671QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item1e594b093f.

That way you can lock them onto the end without it slipping off. Failing this you may be aswel boring out the screw with a drill, start small then work up the bit sizes!.
Hope this helps.
Dov

PeteW

Well I bought a tap wrench and it managed a good few turns, but then won't go any further, it just spins off the bolt. Any further suggestions?

Pete

roger196

I think you are now at the stage of having to drill out. If you know the minor diameter of the bolt (thickness of the bolt once the threads have been removed), you can buy a drill of this diameter and one four thou smaller. You may need a specialist drill supplier like www.cromwell.co.uk , one of the model engineering suppliers or a local engineering supplier. Drill down using the smaller drill. Then try to remove whats left with a scribe. If this does not work go to the larger drill and repeat. Very accurate drilling is required, best to use a vertical miller if you can get access to one.
Another approach is to give up trying to extract the existing bolt. Drill down it using the appropriate tapping drill, and then tap. I have done this on old cars, but you end up with a right mix of threads. I have had studs with BSF at one end and metric at the other.
Your friendly model engineer may be able to lend you what you need. try www.homeworkshop.org.uk with your location.