Drill Through Metal Templates?

[David King]

Terry for my first couple of basses I scribed the cover on to the bass and drilled the pickup corners and tabs to depth with bad point drills. I then used forstner bits to remove the bulk of the wood in the center and cleaned up the edges with a sharp chisel. You could use the same process to make a routing template in 3/4" MDF or birch plywood. A routing template needs anextra 3-4" of wood all around the hole so that your router doesn't tip off the edge. I like my templates to be rectangular with scribed center lines. That way I can just tape the template down with it's center line lined up with the body's center line and my pickups will end up dead center.

You can always buy the routing templates from StewMac or many of the other luthier specialty places.

I agree that doing these types of precision operations are much easier with a milling machine but if you have a simple set of layout tools; a ruler, scribe, square and some patience you can get all the accuracy you'll ever need. A cheap digital caliper is a huge time saver.

[Quarter]

For drilling small one off's or making a master template, I like to draw it out in Illustrator then print it out on label paper or regular paper and use some 3M 77 spray adhesive for larger projects. Punch / mark the centers with a carbide scribe or punch and you're ready to drill. Do make sure your printer is printing at 1 / 1. You can add a known scale to your drawing for double checking.

[Mick Bailey]

For drilling thin material I grind HSS bits to a spur point. The centre guides the bit in the pilot hole and the two spurs cleanly cut out a little disk. The trouble with regular, fluted bits is their tendency to drill a triangular hole in thin material. They also work wonders with fibre, phenolic and softer materials where a standard bit deforms and creates burrs.

[David King]

Mick, that's a really good point especially with thin metal covers. You can buy three flute, solid carbide drills that will give you a round, burr free hole but they need a drop of lube. The ones I use are made by Garr. Ebay has lots of them.

[Joe Gwinn]

Garr also sells direct, though eBay may be cheaper.

GARR TOOL

Select material (brass et al) and tool type (drill), and look for 3-flute drill bits. It's best to use the stub drill length, for better stiffness and reduced breakage (carbide is brittle).

Series 1120 EDP# 78460 will bring one to the 5mm diameter drill.

Use a drill press. even a cheap one. Drilling by hand is going to be a challenge.

[big_teee]

A sharp scribe, and a step bit in my drill press cured my problems.
The step bit is short, and doesn't flex, and I can drill a straight hole in soft material with it.
Thanks guys, for the info.
T