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I've got this washburn 12 string in for a bridge re-glue. There are probably a couple reasons the bridge lifted, first it was glued onto the finish of the guitar, and second the bridge plate is extremely worn.

I haven't ever replaced or repaired a bridge plate before, and was curious about a few things. At what point is it necessary to replace the bridge plate, and can a person get away with simply overlaying hardwood across the bridge pin holes? Especially where the instrument doesn't warrant an expensive repair.

I'm also curious, what are the consequences of a worn bridge plate? I've read elsewhere that the bridge should be thought of as part of the bracing structure of the guitar, I'm assuming the bridge plate is as well? So, if this wears it creates a weak spot where the most tension and torque resides in the top of the guitar. I think Hesh mentioned in another post that this creates an uneven surface for the bridge to sit, causing glue joint failure. Anything else to be aware of here?

Here's a picture of my plate...

I have never replaced a bridge plate but I have had it done on two of my Martins (large plate replaced by small). One of them was a 12 string. The tech who did the work currently shows that as costing $100 and its not a trivial operation.

There are also ways to make little tapered plugs for bridge plate repairs which just looks like a ton of work and there is that metal plate mate thingie. I did do one bridge plate overlay with some carbon fiber on a cheap old guitar that didn't justify any other work.

Looking at your picture and knowing what I do about the work on mine, I would pass.

I have replaced a bunch and try to avoid it at all costs now cause it is hard and risky work. That one looks like spruce and that would be the reason why it is so worn. The Stew-Mac bridge plate saver is one way to repair that kind of damage. I do not do overlays. Doing an overlay on that plate would leave a lot of void area and make the ball ends extremely deep.

It'a involved and risky as the others have said not unlike removing a fret board, very invasive to the instrument potentially and can be a can of worms. We've replaced far more bridge plates than we would have wished to do. We use dedicated aluminum cauls that we made with cartridge heaters to heat things up and then special "U" shaped spatulas/scrapers that can get a purchase under a corner of the plate.

Be warned though heating a bridge plate can compromise or cause the center seam of the top to open..... I have a story of a famous player who didn't want to pay to have this done. He did it himself on a vintage J50 and split the top of the guitar.

This one looks likes spruce which is a lousy choice for a bridge plate on a steel string guitar. Gluing the bridge to finish is also a lousy choice on a steel string guitar and especially a lousy choice on a 12 string steel string guitar.... That's three lousy choices that Washburn made on this one, what are they saving up to be Ov*tion.... but I digress.

So your plate Connor is a excellent example of how the string balls eat away at the edges of the pin ball holes in the bridge plate. Reason: cheap, unspotted bridge pins that encourage the string balls to attempt to migrate upward through the plate, top and eventually close to the bridge itself. This is why unslotted pins are a better idea and it's also an opportunity on better instruments that are woth the investment to convert to unslotted pins.

So the string ball holes get chipped away at and lose material as we see. As it gets worse the now deteriorating holes start to connect and cause weaknesses in the stiffness of the bridge plate. As you recalled and rightly said this can cause a "crease" in the plate not unlike a minor "tenting" of a flat surface and in conjunction with a poor bridge glue joint or RH stress or tension of the 12 strings and/or all of the above the bridge can lift too.

YES you an fix this easily with two .065" thick hard maple (orient flat sawn) bridge plate caps. Make the two strips 3/8th" longer than the six pin holes and bevel the edges. Not sure how wide you can go here and not have the two of them hitting each other but you can figure that out. One single cap is OK here too. This is not a fine, vintage, valuable instrument that someone is enamored with the tone likely, hopefully not. A single maple cap adds a gram and a half so this is not a tone changing thing unless someone has far better ears than I do.

Install the plate/plates, Titebond original is fine and then drill and ream to properly fit the pins and if converting to unslotted and charging for same, we charge for the conversion, this is a good time to do it...When I make my caps I predrill the pin holes and use the two outer ones with special teflon 3/16" rods to locate for clamping which is blind you will find.

This is not something I've ever done, but I can see that a single overlay tapered to snug up to the X braces would be much easier to fit, because you could slide it into the correct position largely by feel.

How about clamping? Would two or three guitar tuners mounted on a caul above, pulling strings up through the holes into a caul below, provide enough clamping pressure? If so, that repair could be comparatively simple to do.

This need not be at all this difficult. Making and installing bridge plate caps is done by commercial shops like our's dozens of times a year and it's a bread and butter activity. Very simple, very fast with 15 minutes being what we take to do the task. A proper cap may only weigh 2 grams or so making its addition very benign for the instrument.

As for clamping I am wondering why you would imagine such a complex approach Chris, it's not necessary and again why not just do it how it's been done for decades and is done every day.

Two long reach clamps, block of wood for a caul just slightly larger than the cap, wax paper around the block so as to not glue it to the plate.... I use two small blocks of softwood on top of the bridge to prevent marring from the clamp. Again this is a 15 minute operation and then we are waiting for glue to dry.

There is some talk at times that this may be a pretty benign place to commit heresy and us CA for the cap. It's faster for sure and this joint will never need to be serviced again. Other than the unforgiving nature of improper positioning CA could be used here, is used here (but don't tell the glue police...) and Bob's your uncle.

I still use Titebond original though because I just get off on having to clean the sludge from glue and wood out of the flutes of my 3/16" drill bit....

As far as clamping, I made several UHMW cauls that fit tight against the bridge plate inside the X braces. I slotted the two 3/16 bolts so they can be adjusted to the pin spacing (and the heads stick down on the bottom so I can get a box end wrench on them in case they get glued into the holes). Glue does not stick to UHMW so there is no danger of gluing the caul to the inside of the guitar. The bolts provide some clamping pressure and align the bridge to the pin holes

I only use these for bridge reglues - as I said before I have never done a bridge plate replacement or a maple overlay, but this is what I would use if I did. Ironically I happen to be regluing the bridge on a Guild 12 string. Bridge plate is perfect and the pin holes will be slotted

Thanks all, this is the info I was looking for.

As a quick aside, because the conversation allows. I've been looking at my D-18 without slotted holes and have been considering making the conversion. I've never done it before. But I have some gauged slotted stew mac keyhole saws. Is it as simple as cutting a slot into the side of the hole and changing over to unslotted pins?

Conor, there are three parts of the slotting question. First, are your holes tapered to fit the pins you will be using? If not do so (some Martins do not come from the factory with reamed pin holes). Second, slotting the bridge allows the string to pass next to the pin entirely in the bridge. The ball still pushes sideways against the pin holding it in. I made a slotting tool by taking a hack saw blade and grinding it down to make a little key hole saw. I then open the slots with jewelers files to fit each string. I have heard of people using a dremel, that scares me. Last is how you ramp the slot towards the saddle. I just do a simple little radius but I know people try to get the proper break angle, whatever that is. One thing about a 12 string is that you can do a little bit to space the strings at the bridge by the way you make your ramps but unfortunately the pin gets in the way of making them as close as I would like. Either turn your pins around or buy unslotted pins.

Looking at this Guild, it has slotted pins but the bridge is not slotted, however it is ramped and looks like good direction to the saddle. The bridge plated (ebony?) is like new. I'm not going to bother about slotting the bridge. The reglue looks perfect, life is good.

Yes - Obtain the new pins and hopefully they won't bottom out right out of the box and there will still be some reaming to do. If you can get 3 degree pins those are preferred but it's a nit as to why and not required by any means. If you want to know what's superior about 3 degree pins we've gone over that here dozens of times so lots of in depth discussions here if you want the details. The short story and the important part is that an unslotted pin goes a very long way to keeping the bridge plate from ever looking like this one by keep the string ball bearing on the flat of the bridge plate (or cap) and not eating away at the edge of the hole. A 3 degree pin has a larger diameter at the point where the pin goes proud in the box of the bridge plate. This fatter pin in this location pushes the string ball even more firmly onto the flat of the bridge plate (or cap) and prevents the tendency of slotted pins to cause bridge plate damage.

I use a set of strings old ones are fine and just cut off the last 6" with the string ball and then here is my process:

1). Ream the pin hole carefully so that the new pin sits a hair proud of having the rings fully seated (in contact with the bridge). I also like to check all six pins in the first hole because many pins these days have poor quality control and are not the exact same diameter. If you get some that are way off you can still use them simply label the pins as to the correct hole with a sharpie or pen.

2). Slot the pin hole with a small slotting saw. You can make your own or SM sells a decent one that's very inexpensive. This is where I use the 6" segments of the old strings with string ball. Slot, trial fit WITH dummy string and ball and continue to slot until the pin seats as it did prior to slotting but with the string in there. Be aware that not all strings have the same thickness of winds and some even have cloth wrapped around the winds. What's important here is that if the steward uses say Tomastiks which require a very large slots your dummy string should be the actual strings only don't cut them and use new ones for the trial fit. Or what I am trying to say Connor is some strings require larger slots try to use what the client will be using so that it does not come back the first time they restring and the pins won't sit all the way down.

3). I have small files for pin slots too and I finish out the well fitted slot with the files improving the uniformity and appearance of the slot and I break the edge at the top on the bridge surface so that the string has a gradual bend here not a sharp edge.

It's that easy.

Not sure who has 3 degree pins these days so I can't tell you where to find them.

One last word from me on cauls. SM sold one a while back that I use a lot it's white UHMW (great stuff or bridge cauls as Freeman said) and it's thinner than what you see here. This caul will ever so slightly flex when the clamps are set and conform to the dome of the guitar top a bit instead of forcing the guitar top to conform to the caul which may be why we see what we see in the OP here.

LMI have single sets in Ebony and IRW, or Gurian of course will make them up for you out of more exotic materials if you buy a bunch of pins at once. although I believe Gurian is temporarily closed at the moment due to the current situation.

There were two reasons I made my cauls that thick. The first was that I want them thicker than the deepest brace I would ever encounter so that center clamp would never rest on on the brace. Second was that was the thickness of some scrap UHMW that I had.....

fwiw - I use UHMW for all kinds of clamping cauls. It can be machined on a mill or cut with a band saw, but it is kind of hard to work with hand tools. Glue does not stick to it so I use it if I expect squeeze out.

Yep it's good stuff and does not stick to HHG or Titebond original.

That tear out between the pin holes has probably been there from the beginning. That's what happens when you just drill right into the top through the bridge place without a backer. I don't think the Stew Mac plug repair tool would work on that one becasue of it.

Jeff, I think it would work because the little cones of wood end up overlapping, so they should fill in all the voids. And if you made the cones out of maple it would last a lot longer.

To be honest, I don't have one of the Stew-Mac's tools but made my own version. In mine the cones are not curved cups but straight cones and fairly wide so they overlap considerably on normally spaced pin holes.

Spruce is an excellent wood for a bridge plate with the grain in the same direction as the top, but the holes needs to be reinforced, or you get what you have in the picture. I use the Stewmac Bridge Saver for this and really hard wood (bubinga) for the buttons, spruce is soft and maple is not really hard enough

_________________
New will change the old,
turn to ashes or gold

http://www.gammelgura.se

Roger, I read your article in a recent GAL rag. I found it quite interesting, thanks for writing that!

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Jim Watts
http://jameswattsguitars.com

Thanks, glad you liked it. That text is the one I have spent most time doing, usually I just write and be done. A lot of work goes into an article like that. Not to mention the years of actual work to gather all the facts

_________________
New will change the old,
turn to ashes or gold

http://www.gammelgura.se

I've done a few bridge plate replacements. Huge undertaking, for the most part, just because it's such an awkward angle and a lot of working blind.

Never tried doing a cap, but I'll keep that in mind!

For damaged bridge plates I've used the SM Bridge Saver many times, and maple plugs. My most recent repair with that I actually did on both sides: the bridge plate as well as the top, as the holes were equally chewed up on both sides. Countersink the holes with the tool, then plug.

I got into the habit of simply pressing the plugs into place. They'll hold themselves in, then I drop CA glue on top. Wicks in and you can see it saturate the entire plug.

Relatively fast and easy, but doesn't sound as fast or easy as a cap. I'll have to give that a try next time around. I do like the Bridge Saver but a cap sounds like it would be much, much faster.

I dislike a cap because it usually is covering voids and does not fill them. Eventually the cap will wear though. I prefer the bridge saver and replacing the bridge pins with un-slotted ones.

Like most repairpersons, I routinely do both types of repair. The SM tool has been my go-to solution in most cases since the day I got it. Faster, cleaner, and IMHO less intrusive as far as possible impact on sound. Well, if I'm being really honest both methods have positive impact on sound.

I too have plugged from both sides with it, such as on Gibsons LGs that needed bolt holes plugged AND reinforcement plates added over the original very chewed-up soft wood while doing plastic bridge replacements. So there's more than one way to skin those cats, obviously.

Nowadays I only use reinforcement plates if the SM tool won't fit in the guitar, that is if the body does not offer enough clearance to fit the tool.


Pierre
Guitares Torvisse

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Pierre Castonguay

Caps are a great answer especially for the crowd that does not want metal in their guitar and thinks that there may be a tonal impact (there isn't but they think that anyway....). A cap can be banged out in three minutes .055" thick, good ole Michigan rock maple and no need to purchase anything from anyone. In either case consideration for possible pick-up interference in installation should be considered as well.

But the best solution is a slotless pin conversion cap or saver and refitting the instrument for slotless pins. We have restored 1870's Martins with slotless pins and there was zero bridge plate wear.

Bridge plate wear on modern steel strings is actually a fairly newer thing and resulting from some genius at a f*ctory determining that if they used mass produced, cheap plastic bridge pins with slots in them they would not have to pay semi-skilled labor to slot the bridge, top and plate for slotless pins as it was in the past.

But what no one cared about or knew is the slot in the pin and to a lesser degree the taper at 5 degrees permits the string balls to eat away at the edges of the pin holes and that's what results over time in bridge plate wear. Unslot the pins and properly fit the instrument for this and there is no bridge plate wear. 3 degree pins do better too, unslotted in keeping the string balls from the edges of the string holes.

My business partner David Colling presented a talk on this subject at one of the Northwoods seminars and he called it the "Deevolution of the Bridge Pin." Many of you who have come to classes at our place may remember the posters on the wall describing this.

I once tried a brass PlateMate and took it out as quickly as I put it in. I got a very nasty metallic shrill from the brass plate for sure. Maybe only noticeable for youngish guys (that I was at the time) still able to hear the crickets.

_________________
New will change the old,
turn to ashes or gold

http://www.gammelgura.se

Well I don't think that there is any way to prove what we hear making this very subjective. I don't hear any difference and if there is any difference in tone it's more than likely because of a change of mass in the bridge area not because of the material of the plate.

One additional objection I have to this device is we are Luthiers we are supposed to me "crafting" much of what we do not buying a commercial, slap it on and forget it solution from the nearest Luthier supply house.