Bridge pin size and angle

[Paul Levens]

Hi all.  I am new here!

Bridge pins have been loose since I bought the guitar, but now one is slipping. Can't measure the hole angle accurately, but 3 degrees is standard on a Taylor.  Hole at the top is 0.217", but pins only 0.200".  I doubt this is hole wear as all are smooth and consistent (modified perhaps?).  Can't find 3 degree "oversize" pins anywhere (even at Stewmac), but 5 degrees up to 0.220" are available..

Anyone dealt with this issue before?  I am not interested in plugging or re-drilling and reaming the holes - too invasive and/or costly.  Any feedback welcome - thanks.

[Russell Vance]

Hi Paul,

If the bridge was subject to shrinkage (wood shrinks laterally mainly with less significant longitudinal shrinkage) the pin holes would get smaller across and along the grain So initially, the pins would be getting/remaining tight.  However, as the bridge pin holes shrink up against the stable bridge pins they will crush down locally and when the humidity changes the pins may then be loose in the squeezed down bore.   That's my understanding of the process and is derived from a distant memory of this counter-intuitive thing. However it also depends on the ratio of the spacing and size of the holes to the remaining wood in the webs between the holes as to how the wood will react.   If this stuff was easy everybody would be doing it.

Rusty.

[Andrew]

I havent read the thread much so maybe someone has pointed this out, but if those are wood bridge pins, they are likely shrunken and compressed as well. Theres a glue available for furniture repairs than swells the wood and then freezes it in place. I wonder if that would do the trick.

Edit: looks like Rus pretty much said this. Whoops.

[Paul Verticchio]

The bridge saddle is in desperate need of replacement.

Best of luck with your bridge pin solution. 

[Ron Frazier]

First you could put a match stuck in the hole and the pin will not get out! Next your bridge saddle is notched for the strings that is a no no! the string slot shows black tells me the string is not touching  the so the string will have a buzzing sound .  Up grade the saddle !  Next is strad could have had supper glue Or titebound I am sure he would used them. The only thing that hide glue is good for is it can be taken apart easily.

The thing I have heard is the builders used to water the hide glue down so when the top shrinks it will not crack the wood but the glue gives loose.

Dose any one knows why they put rattle  snakes rattles in side a violin?

cracks the wood but comes apart. 

I say if it works dont  fix it. Leave   it alone .

Ron

[Russell Vance]

Hi Paul, 

I love refurbishing and bringing instruments back from the "dead under the bed" situation.   I'm an old artificer and its in my DNA to fix stuff.  Which is now a bit of a battle with a lot of everything cheaper to replace than repair because of the necessary cost pressure on my labor.   

But, this is a fine thing if you are a "picker" with a bit of time on your hands which is a joy because so much stuff is repairable if time is not a factor.   One of life's small pleasures is to get a job which allows a rebuild or restoration with a reasonable reward for effort.

And, yes, raising the grain with moisture will leave the grain raised when it dries out, however, it won't be as prevalent as it would be for an instrument in a higher humidity environment.  I'm just going out to soak a wooden bridge pin to see if it expands any......something new every day - love this job. 

R.  

[Mark McLean]

Genius Rusty. It’s not the hole getting bigger, the pin is shrinking. 

Paul, if your house is dry enough to be shrinking the floorboards you need to be seriously worried what it is doing to your guitars. Hydrate them. 

[Mark McLean]

But are the pins wood or plastic?  Many Taylors ship with plastic pins, so that theory wouldn't fly in that case

[Russell Vance]

Hi Mark, ah, not what I was thinking, I gather the bores are oversized for some reason and one in particular has given up first.    Without being there on the spot its just a case of talking to the probabilities and eliminating the obvious stuff.   Its sometimes not possible to work out how the problem occurred and in that case its just a matter of fixing it.   

So, If the theory doesn't fit there is no reason to pursue it.

   .   

[Paul Levens]

Regarding the dryness; yes Mark you are right, but everyone here has used, tried, (effed around with!) room hudifiers, house humidifiers and guitar humidifiers.  We get static shocks off the carpet in winter!  When we have several instruments around each requiring this kind of attention, most of us give up having to enclose each in a humidified case, or constantly de-liming the house device on the heating system.  Old or imported furniture and pianos suffer the same hazard.  Most of us now have older guitars with some dryness damage - just a fact of life here except for the obsessively diligent!

I see the dryness as more of a problem for my vocal chords when singing to be honest.

[Paul Levens]

Indeed Rusty, need to weigh up cost or time invested against reward.  After retiring (3 years ago) I had to re-learn not to put a $ value on every hour I spend (used to earn a good hourly rate).  Now I have that luxury, but when you do this professionally, of course business sense and efficiency are important.

That said; I have lots of time to enjoy tinkering with this fix.  I have other guitars to play for now (lucky me!)

[Walter W Wright]

good stuff, especially the ideas of "wallpapering" the holes with thin veneer or de-crushing the wood in there with soldering iron steam heat.

what's everybody's opinion on 5° vs 3° pins?

i'm finding that when i repair shredded bridgepin holes, maybe by putting on a thin layer of rosewood underneath and filling up all the gaps with a CA/rosewood dust mortar and/or fitting unslotted pins, that with 5° pins there's a problem with the hole in the bottom not being big enough for the ball to fit through before it's big enough fo the pin to be loose in the hole. the pin just gets too "pointy" at the bottom, it's too small right in the area where it's supposed to be supporting the ball end.

3° pins seem to be superior here, you get clearance for the string ball to fit through while still having the entire pin fit tightly in the hole.

hell, cheap ibanez acoustics use 0° plastic pins where it's a straight cylinder and those actually work very well.