Official Luthiers Forum!

On a new build:

1. Slab headstock - Do you drill all the way through with the bushing diameter or use the post diameter and enlarge for the bushing?

2. Bridge pins - similar question - drill to the smallest pin diameter and then ream to the appropriate taper or something else? At this point I am only drilling the bridge.

Using LMI 3 degree pins, will likely use slots as well.

Thanks!!

If you are using bushings then the posts will fit in the bushing holes just fine, as they are designed to, so you really have no choice but to drill so that the bushing inserts fit.

I've always drilled the bridge pin holes to the median thickness of the pin itself then ream it out.

Keyhole slots are always a good idea.

I drill 1/4" tuner holes and then use a violin reamer to enlarge the upper end until the bushing can be pressed in with a cam clamp. I like that it puts the highest stress deeper down in the hole, so the headplate is unlikely to split.

Bridge pins, I drill 3/16" and then ream. The initial hole just needs to be big enough for a ball end to fit through, and big enough for the reamer end to get into. After reaming it should ideally be a tight fit all the way to the bottom.

Do you have a 3 degree reamer if using 3 degree pins?

I drill for pins with a 3/16th" bit and ream to fit with the proper degree reamer for the pins, either 3 or 5 degree. 3 degree unslotted pins was and remains my preference for the benefits in bridge plate health... 5 degree unslotted pins are next in line with most of the benefits and slotted pins are the least desirable choice for me.

Tuner bushings are generally reamed to fit too and there are even stepped solutions for certain types of tuners.

For tuner bushings one other trick that I use is to drill a small pilot hole and then on the top side of the headstock drill with a bit good for the bushing the depth of the bushing. From the back side use the pilot hole to drill through with a bit appropriate for the tuner post. This assumes that you have a drill press or some other way to make sure the holes are drilled square to the head stock.

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http://www.Harvestmoonguitars.com

I use stepped hole for all tuners. Stewmac makes bits perfectly designed for the job.

John, I tried that, but using the pilot hole as my starter for each of the other two, things didn't quite lineup. If that's what you mean. Now, I drill into the drill press table and put a towel in to line up and it works great!

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Pat

I like your way of doing it!

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http://www.Harvestmoonguitars.com

I learned it here!

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Pat

3/16" bridge holes followed by champfer, tapered reamer, and slotting for the string with a jig saw, hand saw and files.

For tuners with bushings usually 1/4" hole followed by the appropriate SM stepped reamer on low speed in a drill press. A hand drill and/or high speed has not worked very well for me.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Yup. And the stepped bit is fairly affordable.

+1 for stepped drill bit.
For bridge-pin holes, 3/16" and a great 3 deg reamer from Murray (murmac)

Brent