But as soon as you get into adding controls or changing things in such a way that you have to break out a drill to get the job done, it all gets a bit hairier. For example, I just built a new solidbody electric guitar; it has a beautiful quilt maple top with a stained finish under a gloss topcoat. The last thing I wanted to do was to crack or chip the finish as I was drilling the final holes for the strap holders, output jack plate, control cover plate, switches and pots, and other hardware.
Fortunately, there’s an easy trick you can use to prevent a guitar’s finish from cracking or chipping when you drill a hole in it. Simply stick a piece of masking tape over the spot where the hole will be drilled. This will help prevent the finish from cracking, and it will also serve a second purpose: it gives you a great surface for making a pencil mark exactly where you want the hole to be.
I prefer to make several passes as I drill a larger hole. First, I use a very small bit to make an initial guide hole, then I expand the hole to the desired size, using progressively larger bits. I take it slow, let the drill do the work (not forcing the bit in), make sure I’m not drilling at an angle (unless I need to), and measure many times to ensure I’m making the hole in the right place! Once it’s there, it’s there…
WARNING: Be careful! Any damage caused by modifying your instrument will not be covered under its warranty. Be sure you know what you’re doing before you make any permanent changes to your guitar or bass! Sweetwater and me ain’t responsible…if you have any doubts, then consult a luthier or a guitar repair expert before attempting the mod.