Gotoh Tune-o-matic Bridge Posts

[guitar2005]

So I'm at the point where I'm getting ready to drill the bridge post holes for the Gotoh tune-o-matic bridge. The posts are 11mm but I can't find a good quality drill bit (i.e. Forstner or carbide tipped brad point).

7/16" is pretty close but slightly too large. any ideas on whether this would be suitable?

Thanks,

F.M.

[ihocky2]

Is there any specific reason you NEED a carbide tipped brad point? I know carbide tools have their bonuses, but unless drilling metal, a good HSS has never failed me and I can resharpen it myself with ease. An 11mm Forstner might be hard to find, but an 11mm brad point should be easy enough. I experimented with a 7/16" and it was a loose fit. A 27/64" was actually a little tight, bit I cleaned it up with a little sand paper and it was fine. But a 27/64" is going to be harder to find than a 11mm.

[Mattia]

+1

Never used a carbide tipped brad point in my life.

[guitar2005]

+1

Never used a carbide tipped brad point in my life.

The carbide tipped point isn't necessary.

I guess I want to make sure I have a super clean cut. I guess that HSS would be more than enough.

This is the best I can find:

http://www.leevalley.com/wood/page.aspx?c=...cat=1,180,42240

Any other options out there?

Edited October 8, 2007 by guitar2005

[MescaBug]

I always drill the posts holes with a 7/16 drill bit. I installed the posts with a soft hammer, they are very tight. Don't know why you guys had problems with the post being loose. Stewmac recommend a 7/16 bit, don't know why you need a larger one...

[Jon]

Stewmac recommend a 7/16 bit, don't know why you need a larger one...

27/64" is actually smaller than 7/16", not larger.

[guitar2005]

Stewmac recommend a 7/16 bit, don't know why you need a larger one...

27/64" is actually smaller than 7/16", not larger.

Yup - and its also > 0.1mm larger than the 11mm bit.

[ihocky2]

27/64" = 10.715625mm

7/16" = 11.1125mm

0.1125mm doesn't sound like a lot, but I found it to be enough to make the bushing a little sloppy. I could easily pull it back out by hand. Which to me means that it is not transfering vibrations to the body as well. Plus that is figuring on the bit drilling a PERFECT 7/16" hole. If your drill press has any runout (which they all do to some extent) will cause the hole to drill a little oversize.

[guitar2005]

27/64" = 10.715625mm

7/16" = 11.1125mm

0.1125mm doesn't sound like a lot, but I found it to be enough to make the bushing a little sloppy. I could easily pull it back out by hand. Which to me means that it is not transfering vibrations to the body as well. Plus that is figuring on the bit drilling a PERFECT 7/16" hole. If your drill press has any runout (which they all do to some extent) will cause the hole to drill a little oversize.

I hate this

I found a nice 11mm Brad Point bit, drilled a test hole in maple and the Gotoh post won't go in unless I hammer it in with force. It is way tight and I don't want to crack the wood as I'm hammering the post in.

I guess 7/16" it is.

Edited November 25, 2007 by guitar2005

[ihocky2]

Before you get another drill bit, try heating the bushing with a soldering iron first. I have found that once the bushing or even string ferrules are hot, they slide into the wood a lot easier. If it works, great. If not, you only wasted about 15 minutes.