Official Luthiers Forum!

Hello,

When doing a bolt on either a butt joint or M&T , when do you drill your bolt holes ...after the box is closed or is it better to drill the end block in a drill press before gluing the top and back on?..then wait with the holes in the neck by marking where the inserts should go with say,  a pencil through the holes in the end block from inside..and mark on the neck..?

 

I'm trying to figure it out before I close the box...Any help greatly appreciated..Thanks

I do it "option #2" style. If you wait and drill them while in the rim, the bit tends to blast through when it exits the cut. That, in my opinion would look pretty sloppy.

So far (only three guitars) I've drilled after the body is closed. I did have trouble locating one hole accurately, and had to plug the offending hole and re-drill. I'm going to switch to a completely machined end block for the next guitar- mortise and mounting holes pre-drilled. I'm also thinking hard about trying an adjustable neck on the next one.

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

I always drill after the box is closed. Then I'm sure that its centered in the mortise as well as the correct depth. If the depth changes during radiusing and you've already drilled, it may be a bit off.
I just take a small block of wood and hold it on the inside to prevent any blow-out. This lets you feel when the bit is all the way through, preventing the drill from slamming into the guitar body when you get through the block. Works like a charm.
-j.

_________________
“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

After the box is closed.
Here's a photo of the jig I use that fits right into the mortise and has two drill guide bushings to locate the holes the same every time. Excuse the fuzzy photo, but you get the idea.

_________________
Hank Mauel

I drilled the holes in the guitar body/head block after the box was done. Just put some scrap through the sound hole while drilling and go real slow before busting through. To find the exact position of the insert in the neck, I took a brad point bit and put it inside the guitar and through the holes. Hold the neck in the correct position and push the brad point bit into the neck. It will make 2 tiny holes. Make these bigger with an awl, then drill. Worked for me. Good luck!
Tracy

_________________
Tracy
http://www.luthiersuppliers.com

I've only done a couple, but...
I drilled the holes in the neck block after the rims were assembled to the end blocks, but before the box was closed. It's easy to do on the drill press and you don't have 'blow out' problems since you can put a backing block in place when drilling.

I sharpened a 6-inch length of 1/4 steel rod and use it to mark the neck hole positions (via soundhole of the closed box) once the neck is rough-fitted.

John

I drill mine after the box is closed up. To locate the holes, I have two short lengths or 1/4-20 threaded rod ground to a point on one end. I screw these partway into the barrel nuts & firmly push the tenon into the mortise, making sure the fretboard is pressed flat against the top.
The two sharpened pins leave dimples in the bottom of the mortise, making it easy to drill the holes in the right spot.
I like Hank's jig idea too, but you'd have to be really consistent in drilling the tenon for the barrel nuts.

I pre-drill and countersink my head blocks ahead of assembly. I jig-up a couple of stops on the drill press and make 6 or 8 at a time. After the rims are glued to the head block I drill through the sides. Then I mark for the inserts in the neck after the body is done.

Long

_________________
"No man ever steps in the same river twice, for it's not the same river and he's not the same man.” -Heraclitus of Ephesus

[QUOTE=Daniel M] I like Hank's jig idea too, but you'd have to be really consistent in drilling the tenon for the barrel nuts. [/QUOTE]

I do it the reverse of your method...I clamp the assembled neck/fingerboard extension down (after the tenon is fine fitted) and use the centerpoint shafts from the inside of the box, through the holes, to mark the drill centers on the tenon.
Six of one and a half dozen of the other.....or, more than one way to skin a cat!

_________________
Hank Mauel

I drill the neck block before its glued onto the sides....

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

I drill mortise and tenon before assembly. I use Cumpiano's barrel bolts and you have much more latitude (and longitude ) for adjustment, if needed, than you get with inserts.

Ron

_________________
OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......