Drilling the top of guitar / control cavity.

Alnico

I am going to drill two extra holes in the top of my Jackson so i can fit two extra pots. There's tons of space as i have the 'Large' control cavity but what i'm stuck on is how to drill through the paint without splitting it.

I can vaguely remember someone telling me you put insulating tape over where you're going to drill but it's a vague memory at best.

Should i drill the hole from the rear inside the cavity through to the top, or from the top through to the control cavity ?
Should i drill a smaller pilot hole or will the drill for the hole size just go through without a problem ?

Any tips would be great.

John_P

I'm no expert but when I've done similar mods (last one was to add a switch for the piezo on my custom 24 while holding my breath).   I put some insulating tape on and drilled a tiny pilot hole them enlarged it and drilled from the top.  Seemed the least likely to cause any splintering or damage.   

Roland

Drill from the top into the cavity. Start with a pilot hole. Then tape up both surfaces to stop splintering. Use a brad tipped drill of the correct size, because you don't want to be trying the widen the hole out afterwards. The advantage of this type of drill bit is that the brad locates in the pilot hole but, rather than cutting outwards from the pilot as a standard drill bit would, it scores the perimeter of the hole first. Make sure that you are drilling perpendicular to the surface, other wise your new knob will be at a slant. Don't try to drill through too quickly. Let the drill take its time. Pushing too hard risks splitting the wood.

Alnico

Perfect !

Thank you guys. 
@John_P ;
I was thinking through from the top as well for the same reason but wasn't sure.

@Roland
A Masterclass !
Thank you sir, that will see me right and very informative.

Brilliant, thank you.