Broken bridge mounting screws.

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Matt Madden
Posts: 34
Joined: Wed Feb 08, 2012 5:11 pm

Broken bridge mounting screws.

Post by Matt Madden »

A screw up....I was mounting a Wilkinson 3 saddle compensated tele bridge, the one without the tele pickup slot, in my walnut tele-deluxe type thing, and I broke two!! of the mounting screws. I guess the pilot holes weren't big enough, and yeah the walnut is pretty hard, but man the screws seem weak.

I believe they broke down the shaft aways, because they are turning without biting, but they are also not coming out easily. i.e. unscrewing them does not remove them.

I think I can get the top part out with a vise grip, but I would welcome advice on how to deal with the threaded part stuck in the hole. Not sure a typical extractor would get it done.

It would be reasonable to ask why I didn't stop after the first one broke. I don't have a good answer. :?

Next I'll have to get some decent screws to hold this thing down.
Warren May
Posts: 246
Joined: Fri Aug 10, 2012 7:00 pm

Re: Broken bridge mounting screws.

Post by Warren May »

Don't feel too lonely, Matt, I just did the same thing with the bridge screws on the Challenge project and there was a broken headstock thread a few weeks ago with a similar problem for those annoying little tuner screws.

I bought a cheap ebay bridge and used the screws that came with it in a maple body and broke 2 of them before I stopped. Those are really cheap pot metal screws. At first, I decided to relocate the bridge but decided it would be better to get them out. I feel a lot better afterwards rather than leaving the broken screw in there in case someone else ever sees it. The bridge covered it if relocated but the fact they were there bothered me.

It's actually not a difficult thing to fix but you will be able to see the plug. StewMac sells a repair kit for headstock screws but it's really pricey. I think I saw one at Woodcraft very similar, a little cheaper but still pricey, but you can probably make one yourself using their pictures as a model for what you need. Those are too expensive for me and I didn't feel the need to make the hole saw. So, I carefully drilled small holes surrounding the broken screw as close as I could. At some point, I was able to remove the broken screw but the area was a little bit of a mess. I drilled a nice clean 1/4" hole. I filled that with a plug, which I did by using a plug cutter and scrap from the body cutoffs. Doesn't look bad at all and better than leaving the broken screw.
Steve Senseney
Posts: 673
Joined: Fri Jan 06, 2012 2:45 pm

Re: Broken bridge mounting screws.

Post by Steve Senseney »

This happens a lot.

I have a pointed awl that I use to stretch the screw hole after I drill the screw hole. I have less broken screws after using the awl to size the screw hole.
Michael Jennings
Posts: 58
Joined: Sat Jan 07, 2012 6:54 pm

Re: Broken bridge mounting screws.

Post by Michael Jennings »

A bit of bee's or candle wax or even bar soap scraped onto the screw threads before driving it will go a long way in preventing this. I almost never drive a screw without wax on the threads, hard wood especially but even in soft woods.

Mike J
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Barry Daniels
Posts: 3223
Joined: Thu Jan 05, 2012 10:58 am
Location: The Woodlands, Texas

Re: Broken bridge mounting screws.

Post by Barry Daniels »

+1 on bee's wax.
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Matt Madden
Posts: 34
Joined: Wed Feb 08, 2012 5:11 pm

Re: Broken bridge mounting screws.

Post by Matt Madden »

Thanks for the help guys. I should have thought of lubricating the threads.

I'm going to plug the holes and move the bridge back 1/8" or so, which is where it should have been in the first place.

I think I'm going to leave the broken screws in there. The repairs will not be visible, since they will be covered by the bridge. I just want it to be solid.
Warren May
Posts: 246
Joined: Fri Aug 10, 2012 7:00 pm

Re: Broken bridge mounting screws.

Post by Warren May »

Moving the bridge is an option if it covers. Drilling a good pilot hole and waxing the threads are very important but the screws for some of the import parts are just horrible. Especially tuners, even if you don't snap them the heads strip out and it's hard to get a good hold on them. Knowing that, I usually throw those out and use ones that I know are a little better quality.
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