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View Full Version : How do you drill holes through lacquer finish?



jermlilly
11-17-2013, 01:31 PM
I have clear coated but forgot to drill a few miscellaneous holes. It's been curing for 48 hours or so. How would I go about drilling hoes without cracking finish.

Also, I know I need to wait a couple of weeks for the finish to cure but could or should I go ahead and string it up get it set up and make sure everything is working? Or do I need to wait for finish to cure before I assemble anything for test run??

Thanks in advance!

jcalkin
11-17-2013, 02:35 PM
If you're drill bits are sharp you should be OK. Small holes should drill fine. Large holes might better be drilled undersize and reamed to final, or drill fairly undersize and then work up through the the bits 1/64" at a time. Anything you glue on will be in the way of your final buff. If buffing isn't part of your plan, go ahead and put it together. I've seen guys string up an instrument in the white, then disassemble it for finishing. What kind of clear coat did you use?

jermlilly
11-17-2013, 04:59 PM
I used a clear gloss lacquer from stewmac. After it cures I will be final sanding it as well as buffing and polishing.

I don't think I'll be gluing anything down. I have the holes for the peg heads drilled but not the screws that hold the machines down. And then I'll have to put some small screws in the back piece to cover up the cavity I routed out. Other then that I would just have to run the pick up ( mi-si ) through the hole in the saddle and tighten down the endpin and put some strings on. I've done nothing to the nut and saddle so I'm sure there may be action, etc problems but would love to see if this thing works.

Beau Hannam Ukuleles
11-18-2013, 06:11 AM
ive done this- and i know others very good makers that do it on purpose and completely finish, cure and buff the headstock first before drilling out the tuner holes- the tuner holes create little buffing compound lumps/bits/thingys that are annoying.

SO drill now or later. And is there ever a time when you really want a blunt drill it?

oh yer- for clean holes use the following method, with or without finish on it.

1- Using a brad point bit, set the depth stop so that the middle point of the bit will just poke out the back of the headstock.
2- Drill all holes almost all the way through
3- flip it and finish the holes from the back using the holes just poked through from the brad's point as pilot holes.

jcalkin
11-18-2013, 11:58 AM
ive done this- and i know others very good makers that do it on purpose and completely finish, cure and buff the headstock first before drilling out the tuner holes- the tuner holes create little buffing compound lumps/bits/thingys that are annoying.

SO drill now or later. And is there ever a time when you really want a blunt drill it?

oh yer- for clean holes use the following method, with or without finish on it.

1- Using a brad point bit, set the depth stop so that the middle point of the bit will just poke out the back of the headstock.
2- Drill all holes almost all the way through
3- flip it and finish the holes from the back using the holes just poked through from the brad's point as pilot holes.

Good tips, Beau. Nobody wants dull bits, but everybody has a few. For the tuner holes he could also drill all the way through with a 1/16" bit, then come in from both sides with the brad point. I often drill tuner holes before finishing using a bit one size small. After finishing I ream away the junk on both sides of the holes, then run the correct drill bit through using a tap wrench.

jermlilly
11-18-2013, 01:36 PM
Appreciate all the help. I have already drilled the holes for the peg heads( before lacquer). I only have to drill pilot holes for the screws that go on the back of the peg head. Just the 2 screws that hold each tuning machine to the back. And basically the same thing for the back panel. So nothing real big just some screw holes.

singsong
11-18-2013, 01:55 PM
For large holes I start with a pilot hole and then use a step drill bit for the final hole, it drills a clean edge hole. I use 1/2 inch for installing pickups.

thistle3585
11-19-2013, 04:11 AM
I use tape and a sharp brad point drill for large holes. For smaller holes where I don't have a brad tip, and have to use a twist bit, I run the bit backwards so it scrapes through the finish instead of cuts through it. Once through the finish then I'll change the direction. Since I build a lot of electrics, I often drill and rout after finishing. I don't like to wet sand with holes because the moisture can get between the finish and lift it and/or discolor it around the holes.

jermlilly
11-19-2013, 10:51 AM
Awesome. We'll see what happens after about another week or so.