Drill size for bridge pins?
 

I am replacing the bridge in a cheap guitar and would like to know what drill bit to use. At frets.com I saw one article that recommended to start with 3/16, hinting that you may have to go bigger after trying pins in the holes. Can someone please confirm that this is a good way to go? I don't want get sophisticated and do tapered holes for this project. Thanks.

Bridge pins are tapered though. I start with about 3/16 and then use a tapered reamer to size the hole.
I match the drill size to the small end of the pins. You want them snug all the way through the hole both slotted and non slotted pins.

I did not know what to do when building my last guitar, I did not have a reamer but with pins being tapered you kind of need it. Came up with my home made reamer. I took a piece of 1/8" steel and cut it into a triangle shape with the same angle of the pins (can't remember what it is, just look it up). Drill the hole smaller and rotate the 'reamer' in the hole till the pins fit in. Just putting a good right angle with a file on the edges was sharp enough to cut into the wood. Worked quite well.

http://i406.photobucket.com/albums/p...pscbb48384.jpg

Ok, thanks...I guess I will have to look into a reamer.

Yes start with either a #11 or 3/16" bit. The most common tapers are 3* & 5*. There are about 4 common pin sizes (1, 1.3T, 2A & 4.2C) so it helps to know size and taper that you are working with.

I use #13 bit.

Measure the width of the pin about half way up and there's your drill bit size. Then you need a reamer. You might be able to get away with using the tail on a rat tail flat file as a reamer provided it matches the taper on the pin.

Working in wood allows you to use less hard, less expensive tools.

You can get a cheap reamer from Harbor freight for well under $10.

Thanks all. Just bought this cheap set on eBay,
http://www.ebay.com/itm/BEADSMITH-WO...item51ad95864e
should be good enough for my $65 guitar.

you need one like this.
http://www.ebay.com/itm/Luthier-Tool...item1e812eb0cb

the one you bought is probably to small

Not just any reamer will work, it needs to match the taper of the pins or why taper at all

Murrmac123, I think his name is Murray is a sponsor on the forum here and he sells a reamer like the one Printer made in this thread, I have never used one but they look like they would do the job and are 5 and 3 deg to suit guitars. They are much cheaper than the machinist reamer of 5 and 3 degrees but can't remember prices, I think he has them up on ebay though. Some of those cheap ebay machinists reamers are greater than 5 degrees so not really so accurate for bridge pin hole.

Jim

Those eBay and Harbor Freight reamers are called "plumber's reamers" not luthier's and that pretty much says it all.

Half-fluted reamers are easy enough to make. Grind or file a metal rod to the proper taper, say, by chucking it in the drill press. Once you've got that, file off a little less than half the diameter to make a 'D' shaped cross section. This cuts by a scraping action. If you're not doing too many holes you can make one from aluminum that will work fine. Mild steel will go for quite some time. I made one from drill rod more than thirty years ago that's still going strong.

Yes the half fluted reamer that Alan speaks of is fine option imo. In 2008 I took a tapiered piece of mild steel to a guitar making school I was attending. It was slightly abrasive from the grinding wheel I had held it up to while I rotated it in a hand held drill. I was happy with it at the time as it had already worked for me. When the teacher saw it he filed it to a D shaped profile by hand in less than 5 minuites. I used it on several guitars before changing to hand reamers. I'm still new to hand reamers and have found (to date) that I have to be just as careful to not ream to far as I did with my home made reamer rotating in a power drill.