safe way to drill witout messing up finish

[dougray]

hello,i recently purchased and upgrade pre-amp but the 3 tone control pot. shafts are slightly larger than the old ones,how do i drill the holes without cracking the clear finish? i was thinking of masking tape over the holes and drill slowly? any suggestions?,the holes only need to go slightly larger(bass/mid/treble) controls,thanx..

[Hambone]

How much larger the holes need to be will be the determining factor in how to enlarge them. If it's something like the thickness of the finish, then a round file will work well. If it's much more, then I would use a tapered reamer from the back of the hole. That's a tapered steel shaft with 6 sharpened blades running it's length and is used precisely for this type of alteration. The problem is trying to center a drill bit in a hole that's nearly the same size as drill used to enlarge it. That's very hard to do and even harder to do without some damage.

BTW, taping the hole will help like you've observed.

[dougray]

hello,i found an unorthodox way of doing it,i used a metric tap/die set(metric) i found the same size tap as the control pots. and went to next size up,i actually used 3 taps ,slowly making holes larger,it worked like a charm!,no chipping/cracking of the finish. all it took was going slow and patience,thanx for replies.

[Hambone]

Doug, that's a cool solution. I like using tools in ways that weren't thought of by the designers.

Ok everybody, get out your metric tap & die sets!

Whaddya mean you don't have a metric tap & die set??

[merlin]

Originally posted by Hambone
Doug, that's a cool solution. I like using tools in ways that weren't thought of by the designers.

Like screw drivers? They can be used for anything.. like chisels or scrapers, levers hmmm the list goes on. hehe

Metric.... phhftt come into my workshop buddy.



Merls

[pkr2]

Dremel Tool.