Luthier friends — bisecting calipers or something else?

[mathias]

Hi all!

I’m trying to center a control plate and a neck pickup ring for a guitar I’m putting together. The body was cut and shaped by someone else and there’s no screw holes for what I’m doing.

Am I overthinking this in trying to center the plates? Do I need a bisecting calipers? I measured with regular calipers and took the half from the inside of the routing, but I’m worried once I Drill it, it’ll look off. I’m also trying to center in both directions so that I don’t tear out this semihollow top by drilling a hole too close to the cutout. Ideas, suggestions, and so on?

[kosta]

Hey Mathias. Has the bridge been located / placed yet? I'd mount the neck and the bridge and the tailpiece first, then string it up and make sure the strings are falling straight down the neck (checking for even spacing from either edge of the fretboard.) Once that's all sorted out, I'd float the pickups and rings in the cavities and get the pole pieces lined up nicely with the strings. Once that's all aligned, I'd mark the holes for the rings and drill away. I sometimes lay some painter's tape down on the body for marking holes. It can also help a bit with chip out from drilling. If you mess up the holes, you can always fill them with wood glue and dowels and do 'em again. It's not eh end of the world. Your mistakes will likely be hidden by the rings.

Hope that helps.

[mathias]

Thanks! It is a Tele so the bridge pickup will be on the bridge itself. Leaving just the neck pickup and the separate controls plate. I’ll give this a try. I’ve had the neck on but have not yet committed to the rest.

[kosta]

Oh nice, that should be a bit simpler then. For the control plate, I'd get the pickups and bridge installed and get it all strung up, and then I'd locate the control plate by eye relative to the strings and bridge plate. Might not be a bad idea to mount the pots, switch and jack to the plate (even if they're not wired) before doing this just in case they bump up against the edges of the cavity.