Official Luthiers Forum!

Sometimes the bridge pin just refuses to seat, and as soon as you apply tension to the string the pin pops right out and flies across the room!

A customer has a guitar with camel bone bridge pins and for whatever reason I cannot get the string ball to move aside and sit on the bridge plate rather than right under the bridge pin, so as soon as you put tension on the string the pin goes PIINNNGGG and flies about 10 feet across the room. It scares me and I can imagine it may cause the customer a lot of headache... what can I do?

What tool should I use to slot the bridge pin hole, if that will help? I tried using a broken coping saw blade and it takes like 30 hours to carve ONE slot, because I get only 1/8" of stroke.... and my hand turns numb afterward.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Jigsaw blade, a very fine one. Make a handle for it. It works but I'm pretty sure that it's possible to make one that works better. Just need some saw steel and a file.

That hole isn't very big and anything small enough to fit in that hole will also be very flexible...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Stew Mac has tools made from jig saw blades that are stiff enough to hold up, yet small enough to fit into the hole. You can also carve a slot using a Dremel with a bit shaped like a small ball. I have several sizes of theses for the various string diameters.

The reason the string is pulling the pin out is the ball end gets stuck on the end of the pin. Two options are 1) sand the very end of the pin so it has a slant which will make the ball end slide off and up to the bridge plate, or 2) bend a slight curve to the string just above the ball end to do the same thing. When you are setting the pin, hold the string and make sure the ball end is in the proper place before tightening the string.

+1 to what Barry said. Jewelers files also work pretty good, I rough it out with a dremmel and finish it up with a file.

_________________
A man hears what he wants to hear, and disreguards the rest. Paul Simon

I did both of these things... and it actually made things worse!

The difference is I had to overlay the bridge plate with a piece of rosewood about .090" thick, because the original bridge plate is badly damaged (it has the classic split across the pin holes) which caused the bridge to pop loose (otherwise it would have actually cracked across the pin holes). It's a lot easier to do this than replace the bridge plate, which honestly I do not know how to do working blind. I tried bending the string ball end and it just refuses to sit where they need to sit.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Forgive me if I'm off base here. I'm rather inexperienced. I'm assuming you're using slotted pins? If you file/cut a slot in the bridge, make sure you turn those pins 180 degrees or go with an unslotted pin. Also, how does the pin fit in the hole with no string tension? Sloppy? Just right?

_________________
sweat the small stuff.

It fits loosely... problem is once the string is in the fit becomes very tight because of the double winding at the ball end of the string.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Sounds to me like the pin holes in the plate overlay are too big. I don't think the overlay is the correct repair, but I've never tried to remove a bridge plate from a completed guitar, but I'm sure someone here has. Glad I don't have to do repairs!

_________________
A man hears what he wants to hear, and disreguards the rest. Paul Simon

I tried making them too small and the ball end wouldn't even fit even if the bridge pins will fit fine. I did the overlay thing because it's a lot easier and I don't think the customer would want to pay for a bridge plate replacement given the value of the guitar... it was a Yamaha. I'm sure it's possible but I can't think of how I can remove a bridge plate working blind. I have enough trouble with clamping bridges already. Either the clamp doesn't have enough reach because the particular guitar has such distance between the bridge and the soundhole, or it's too much reach because the guitar is too small. This particular guitar has a shallower body than usual which will make such repair much more difficult. Frank Ford does overlays on some guitars from what I see so I see nothing wrong with them if the value of the guitar aren't that high.

I'm just not sure how I can get heat to the bridge plate without extreme finish damage... plus when heated to the right temperature how would I go about removing them? I don't think I can put a palette knife under that...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Don Teeter's repair book shows how to remove bridge plates using a few special built tools. It is still a rather complicated repair but the best way to go about it. I think an overlay is poor technique. It adds excessive weight, and the crack in the original plate may telegraph though the overlay eventually.

Sounds like your problem is poor fitting pins and no slot (in either the pin or bridge).

I've always used a narrow jigsaw blade that's been ground down a little more to fit in the hole, and a jeweler's file to clean up.

I test the slot size with a string when doing this. With the bridge pin inserted, you should be able to pull the string until you feel the ball end butt up against the bridge plate, without excessive resistance.

A coping saw blade wouldn't cut nearly a wide enough kerf to fit a wound string end.

By the way the bridge plate overlay's grain is right angle of the original bridge plate, so it will not telegraph.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I have no idea, since I am new to this, and have never attempted such a repair. But I do wonder, is it possible to size the pin to make it bigger? Thinking successive thin layers of super glue maybe, just enough to gain a few thousandths?

Or, is it possible to plug the hole, then drill and resize to correct taper?

_________________
Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

When I'm stringing, I put all 6 strings in the bridge, at once and put my hand thru the soundhole to make sure they seat properly against the bridge plate.

Without seeing it, it almost sounds like the new bridge plate makes it too deep to seat the ball against it, especially if the slots are there.....

Did you shamfer the bottom of the bridge pins? It stops the pin from grabbing the ball end

I slotted the hole, it solved it.

thanks for all the advise.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com