Bridge screw up and fix

[TonyinNYC]

I am building three guitars right now. Two will have 2.25" string spacing at the bridge, one will have 2.125" spacing. I made the bridge for the 2.125" spaced guitar, located it using my KMG bridge setter, and drilled the locating holes and the holes for the 1st and 6th strings. That all took place about a week ago.
This morning I got up and realized I might have goofed. I measured the spacing of the two holes on the soundboard and sure enough I had made the holes 2.25" apart on center. I also lost the bridge so I needed to make a new one anyway. But now, my choices are the following to fix this mess and my thoughts about each method in red:
1) Do nothing. Widen the two holes that I already made by .0208"(the difference in string spacing of .125"/ 6) towards the center line of the top and move on.
Seems logical and non-invasive. .02", is not very big and this option has the least room for errors.

2) Plug and redrill the holes in the soundboard and bridge plate, do nothing else, and carry on with finishing the guit
Also a good option, but the chances of the plug remaining intact as I drill out the new holes seems pretty small to me.

3) Pull the bridge plate, make a new one and install it. Plug the holes in the soundboard with spruce. Drill new holes and proceed as normal.
This option makes the least sense to me. It is the most invasive and the chances of doing damage to the guitar are the greatest with this option and gluing a new bridgeplate in blind when the current one is sound does not seem like a logical choice.

The other facts you should know about this guitar are that the finish is already applied and the neck can not be widened to accommodate the wider spacing at the bridge since it is already finished as well.

What do you all think?

[John Parchem]

I will be interested in any answers I have a guitar that I would like to move the bridge over a little more than a 1/10 of an inch.

I removed one bridge plate from a top that was not on a guitar. That was hard enough, I can not imagine doing it with a mirror and my large hands. Stewmac has a tool that cuts plugs for the bridge plate and cuts removes the material to allow the plugs to fit.

[Tim Benware]

I think your math is off. You have the outside holes at 2.25 ON CENTER right? And you're 1/8" (.125) off, then the centers of those holes need to move equidistant toward each other or .125/2 (not 6) which equals .0625", taking off only .02 on each side would make your distance 2.21. If it was me, I'd clamp a backer block to the bridge plate and using the outside holes of the bridge as a drill guide, re-drill the holes. The backer should help reduce chip out. (edit - this is option #1)

[TonyinNYC]

Good point Tim.
It is still only a sixteenth, but plugging and re-drilling seems doable.


There is one other solution I had not thought of at first: pinless bridge!!
This was suggested to me by a luthier friend from Holland. It is simply brilliant! Now I just need to figure out how to make one!
It is an elegant solution to every problem I am facing now.
Thanks to my friend Edzard Kolks for the great idea!

[Tim Benware]

I've made several pinless bridges and depending on the design they aren't that hard. The tension steel develop always gives me concern that the bridge may lift after a while i.e. the full tension pulling on the bridge and not being reduced by the bridge plate.

If you have a cross mill vice to drill the holes it's best but even good measuring and placement will get you there.

[TonyinNYC]

How big of a hole do you drill for the strings to pass through?

[Tim Benware]

Here's one I did for a Harmony after a neck reset, the original bridge had been shaved down too low. These strings are fed through the front but you can also come in from the back and make the bridge any shape you like.