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Of course, I still have these rather disreputable-looking examples
A hand reamer is a thing of beauty. I really should get one, up to 12,7mm would do nicely. I have this little project with an acoustic guitar, that needs a pickup. The noveau-classique way to fit the phone jack is to replace the shoulder strap knob on the body with a special 1/4" jack that not only serves as output but also as knob. (The phone jack also serves as power switch to the preamp in the pickup, if it's active. Shorting ring and sleeve grounds the battery circuit and powers the preamp.)
A thing of beauty when used to deliberately make conical holes, a horror when used to make holes that ought to be cylindrical by their nature.
This little babe came from Luthiers Mercantile International (
www.lmii.com). It's set to exactly the angle (3º) that's used as standard for end pins and for string retaining pins (there's also a 5º standard as well, but 3º is the commonest). Note that it has teeth only on one face, the other is smooth and that feature is crucial to maintaining concentricity when reaming by hand. This is the 'economy' version that comes in at a mere $73 at current prices, the posh German one they sell is $170. Mine has been used a fair bit, I've never sharpened it but it's still so sharp that I could cut myself on it. You don't actually
ream out the hole, you just turn it a few times under very light pressure until the entrance hole magically becomes the right diameter and some sawdust dribbles out the far side. Presumably the $170 German version is so sharp that it needs its own special holder so that you don't inadvertently lean the edge on something like the tabletop and cut through it.
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The holes it cuts are so precise that I've never had to glue an end pin; they are smooth and perfectly concentric with the [lathe cut] pins. A light tap with a leather faced mallet and the peg is in there for good.
However, you won't need one for an end pin jack, all the ones I've encountered go into a
straight 1/2" hole (L.R.Baggs and impersonators) or a straight 1/2" hole that is then tapped to a 9/16"–12 thread (Switchcraft, need I say more?). (Standard end pins are 1/3" at the fat end.) So a standard 1/2" spur lip drill is going to be your weapon of choice, along with some very careful clamping and fixturing.
If your pillar drill is capable of being reversed (to overhang the edge of a bench) then some judiciously shaped clamping blocks (with something soft like felt, foam or leather on the faces) and some wide carpenter's clamps are the way to go. That's how I've always drilled out the holes for end pins. Needless to say,
only clamp with any force on the end block with only the lightest clamping force on the very edges of the guitar itself to stabilise things and
none at all on the unsupported soundboard itself. (Soundboards seem quite firm when they are on the guitar but they are immensely fragile things and will crack along the grain with only the slightest persuasion.)
I've had the advantage that when doing it I've only had a body to deal with, before the neck is glued on - you might have problems finding the height to fit a whole guitar, neck and all, in between the floor and the drill, with something at the right height to clamp the body to.
There's something very unnerving about taking a 1/2" drill bit to the bottom of a mostly finished guitar. Taking one to a completely finished guitar would be nail biting. Definitely the kind of job that you spend a couple of days rehearsing inside your head before eventually going for it.