When it was going so well..... broken screw!

[Robbie010]

All seemed to be going swimmingly..... the dubois depraz module went back together (with a few hiccups along the way) and seemed to be functioning well..... left it overnight and when I came back to it a screw top has pinged off

Looking online there are a number of extractor tools, the Bergeon one coming in at £100+ with the various bits or the Chinese ones at around £30 - £40 with a load of bits included!

I think I already know the answer to this question but I’ll ask it anyway..... am I best forking out the £100+ for the branded tool or has anyone had any positive experience with the generic Chinese tools!??

[Marc]

I believe that there have been some comments on here in the past regarding the Chinese offering which suggested that the two bore axes didn't line up very well.

However, before you part with your cash, have you tried using a fine pointed needle to rotate the broken part of the screw out? If you have access to both ends of the screw (which you must have in order to use the extractors anyway) then the screw shaft isn't tight against anything once the head has sheared off, which means that there is a good chance that threaded part will just unscrew, and a fine needle point should be able to get enough purchase in the broken top of the shaft to turn it.

[nickelsilver]

I have the Bergeon extractor, an old one so "old school quality", I don't think it's ever actually worked for me. Also, the standard tips are too big for most modern stuff. I agree with Marc, try backing it out. Very often the remaining bit is actually loose once the head comes off.

 

If it's tight, I've had better luck than the Bergeon tool using a jeweling tool, using a pusher and stump that effectively do the same thing, clamp the screw by its ends, then swing the plate/ part around. Often have to make up pusher and or stump to fit, but it's a few minutes work.

 

In the really bad cases the part goes on the jig boring machine and gets milled out. Yuck.

[clockboy]

I do own a Bergeron screw extractor and I have only used it twice over a number of years. It worked both times with no effort. It depends where the broken screw is it might be possible drill a hole in its middle and twist out with a small broach. Before I purchased the screw extractor I did try the Alum trick but I had no success hence the purchase. 

[Robbie010]

The pin trick worked a treat, a bit fiddly but once it was out a tad I could get purchase with the pliers to twist it the rest of the way out. 

Thanks all. 

[clockboy]

[MechanicMike]

Horetec has a driver but instead of the usual screwdriver blades for bands and such, they blades that have been sharpened with individual sharp teeth on the diameter of the blade, with the thought of them "biting" into the broken part. Thought of getting one myself. Don't have the link handy tho sorry.