1. A proposal is now up as a poll to change the guidelines of TGP to only allow member self-deleting of post/threads for up to thirty days of the original posting it. We are now watching the poll here. Click here to view the thread.

    Dismiss Notice

Broke a screw off in my headstock! :/

Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by Crowder, May 21, 2011.

  1. Crowder

    Crowder Dang Twangler Silver Supporting Member

    Messages:
    16,804
    Joined:
    Jun 1, 2009
    Location:
    Chattanooga, TN
    I was installing a set of Gotoh vintage tuners on a new Musikraft neck. I pre-drilled all the holes, but probably should have used a bigger bit. One of the retaining screws broke off, leaving half the screw in the wood and the other half loose. The top of the screw that is in the wood is below the surface. Argh!

    I know they make gizmos for extracting screws when the head is stripped, but I'm at a loss on how to approach this situation. Any ideas?

    Thanks,
    Mike
     
  2. Sweetfinger

    Sweetfinger Supporting Member

    Messages:
    10,589
    Joined:
    Jul 16, 2008
    Location:
    Phoenix, AZ
    there is an older thread somewhere on exactly that.
     
  3. hank57

    hank57 Silver Supporting Member

    Messages:
    7,395
    Joined:
    Aug 4, 2006
    If you have a drill press and can lock the headstock in place maybe then you'd drill directly in to the screw till it is gone. Basically using a bit smaller or larger. Then put a dowel in the hole with glue and start over.

    That is my hack version of fixing it. Wait for a luthier to say what to do.

    Good luck and I have done this before but the crews was tall enough to hold onto with pliers or vise grips.
     
  4. nateclark

    nateclark Member

    Messages:
    437
    Joined:
    May 29, 2007
    Location:
    Ithaca, NY
    If it's too small for an easy-out screw extractor, you can drill a couple of holes right next to the screw and use some small needle nose pliers to rock it out. Then drill the whole mess out with a brad point or forsner bit and make a corresponding plug from maple, or whatever the neck is. If you're meticulous, you should be able to keep the plug at 1/4".
     
  5. Sweetfinger

    Sweetfinger Supporting Member

    Messages:
    10,589
    Joined:
    Jul 16, 2008
    Location:
    Phoenix, AZ
    I searched a bit but couldn't find the old thread. What you do is buy a small piece of brass tubing that is *just* slightly larger than the diameter of the sheared off screw. carve some teeth in the end of the tubing with a file or a Dremel cutoff wheel. Chuck the tubing in a drill and set the drill in reverse. Basically, place the tubing with the teeth right over the embedded screw shaft and start drilling. The teeth cut down around the screw and when they get far enough in the bit of screw will pull out inside the tubing. The reason you use reverse is that hopefully, the tubing will reach a point where it locks around the screw and unscrews it the rest of the way. This leaves a hole exactly the size of the tubing which can be plugged with dowel and redrilled.
    Yes. If a screw is requiring lots of pressure or force to go in, you need to back it out and use a larger drill bit. If you are using the correct screwdriver and are still raising sharp burrs on the top of the screw, same deal.
     
  6. pennylink

    pennylink Member

    Messages:
    1,844
    Joined:
    Sep 8, 2007
    Location:
    London, UK
    After removing the broken off screw and plugging the hole (as described above), redrill with the correct drill bit and use a little wax on the screws. Any wax, even candle wax helps to lubricate and reduces friction that causes small screws to break. I do this with all my woodworking projects and especially when working with harder woods such as maple. Makes a big difference.
     
  7. Tidewater Custom Shop

    Tidewater Custom Shop Performance Enhancing Guitarworks Supporting Member

    Messages:
    5,670
    Joined:
    Jul 22, 2008
    Location:
    Under a stack of textbooks
    ^^^ Good advice from pennylink. I use paraffin wax, available in most grocery stores in canning supplies. Use pliers to hold the screw, heat the screw and 'dip' it into the wax block. That puts a thin coat of wax on the threads.

    [​IMG]

    Here's my kit for doing this kind of work - it costs about $15.

    I chose a plug cutter to get the same grain orientation as the rest of the surface on the work area.

    [​IMG]
     
  8. SamBooka

    SamBooka Member

    Messages:
    2,227
    Joined:
    Dec 8, 2009
    Location:
    Montreal
    A pic would help.

    If a little bit of the screw is still sticking out of the wood you can sometimes grab it with the chuck from a hand drill and back it out (remove the tuner you were installing first)
     
  9. Crowder

    Crowder Dang Twangler Silver Supporting Member

    Messages:
    16,804
    Joined:
    Jun 1, 2009
    Location:
    Chattanooga, TN
    Just checking back in here to report my results and thank everyone who chimed in.

    I used some guidance from the TDPRI thread posted above. This involved cutting off a short piece of brass tubing, filing some teeth in the end, and cutting around the screw until I'd removed enough material. The screw actually came out inside the brass tubing. Then I cleaned up the hole with a 3/8" bit and glued in a 3/8" dowel. I used the very end as you can see from the black paint on the dowel. I'll sand it completely flush and the tuner covers will cover the rest. Should be no visible evidence of the repair.

    I'm pleased and grateful. I did get a little chatter around the hole from the brass tubing slipping a bit before it got into the wood, but I think it will look plenty clean when the tuners are on.

    Incidentally, the screwhole to the LEFT of the repair was piloted with the too-small bit. The one to the RIGHT was piloted with the correct bit. Big difference.

    [​IMG]
     
  10. Schmidt

    Schmidt Member

    Messages:
    145
    Joined:
    May 22, 2011
    Location:
    Denmark
    Exactly! That's the right (and only) way to do it.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice