Do you use inserts for pick-up screws on your builds?

Discussion in 'Luthier's Corner' started by cnltb, May 2, 2019.

  1. cnltb


    May 28, 2005
    The title says it all.
    I would also be interested in hearing the benefits you see in using insert or not having them.
  2. Gilmourisgod


    Jun 23, 2014
    Cape Cod MA
    I haven’t so far, but may next build. The only downside I see is that they aren’t available locally, the postage to mail order exceeds the value unless you buy a bunch. Probably have to go through McMaster Carr. Do you have a source like Amazon? My G&L L2k has pup and battery cover screw inserts, very nice,
  3. HaMMerHeD


    May 20, 2005
    I've done it before, but I don't anymore. Those tiny inserts just don't hold on to the wood very well unless you glue them in, and I find that is difficult to do without getting adhesive in the internal threads.

    I think a better approach might be to adapt @Bruce Johnson 's neck mounting approach to pickup mounting. That is, glue big brass blocks in place, then drill and tap those blocks for the pickup screws.
  4. cnltb


    May 28, 2005
    Thanks to you two for your input!
  5. Gilmourisgod


    Jun 23, 2014
    Cape Cod MA
    What's the size of the screw? I didn't know what the length or thread count would be to search Mcmaster Carr. The brass ones in my G&L have held up for 36 years, can't tell if they are glued in or what. The neck bolts on my old 86' Steinberger XP-2 were screwed into brass inserts that were knurled, no threads. One of them failed after 30 years, but it was the CF/Resin in the neck that gave out, not the insert. The Brucebar makes sense for neck bolts, probably overkill for a pup. No real torque put on it unless you are a Gorilla.
  6. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    Like most subjects here on TB, this has been discussed many times before. Here's a post of mine from some years back:

    I used threaded inserts for the pickup mounting screws on the basses I built for the first several years. I used 4-40 socket head machine screws, either stainless or black. The best inserts I found were actually Hex Threaded Standoffs, available from electronics supply houses. It's a short length of 1/4" hex brass bar stock, drilled and threaded 4-40 down the center, nickel plated. Relatively cheap, available in different lengths. I was using 4-40 x 1/2" long.

    Very simple to install: Drill a 1/4" hole x 1/2" deep. Lightly press (or tap with a hammer) the hex standoff down into the hole. The points of the hex digging into the wall provided plenty of friction to hold the insert in the wood, for a light-duty application like pickup screws or control cover screws. Simple and reliable, and can easily be extracted if you need to change one for some reason. You can put a little bit of glue down in the hole if you like, but it doesn't really add much to the pull-out strength.

    But, with all that said, I stopped using threaded inserts for pickup screws back around 2000. Too many problems with the pickups vibrating out of position. A bass is a big 'ol vibrating machine. That's what it does when it makes noise. Machine screws into threaded metal inserts have very little friction, not enough to lock against vibration. The springs and foam typically used under pickups are way too soft to act as lock washers. You'd have to use very stiff springs to keep the screws still. Or, put Locktite on the threads. Which kind of defeats the purpose.

    That's why I gave up on threaded inserts for pickup screws. And I don't recommend them. Unless you are building a real bench mule instrument, where you actually are going to change out the pickups hundreds of times.

    These days, I still use the 4-40 socket head machine screws, but I thread them directly into the wood of the body. I drill a pilot hole (#42 in maple, #43 in other woods) and just drive them in. I use screws long enough to have 3/8" of engagement in the wood. The wood grips the screw well enough to hold them against vibration. Very reliable. Over the years, I've only had a few strip the threads in the wood. Easily fixed with a drop of glue and a waxed screw.​