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Troll 01-09-2020 05:39 AM

Bridge Doctor
 
Do any of you have experience with guitars that have been repaired with a bridge doctor device? Iím interested in a Vintage Guild D-25-12 with this repair, but am concerned. Before I drive an hour to look at the guitar, I thought Iíd seek your expertise. My first thought is that this may be a temporary stopgap solution that will eventually require a permanent fix. Am I off base here? Iím also concerned about tone as this device produces upward pressure on the bridge and may have an adverse impact on top resonance and sound quality.

As always, thanks for sharing your wisdom.

Troll 01-09-2020 06:13 AM

Disregard....30 minutes of research has told me all I need to know. Iíll pass on this one. Thanks anyway, go on with your day😎

DavidE 01-09-2020 07:27 AM

The price would have to be very low for me to buy one with that kind of repair and I own one with a bridge doctor repair. Not sure it's needed on mine, but my Taylor 810 was scrapwood when I got it and is now a great playing functioning gigging guitar. But it's market value isn't close to what one would be that didn't need it.This one just had so many repaired top cracks the luthier thought it was a good insurance policy. I have very little in the repaired guitar. Plays better than most of my others now. Maybe all of my others. LOL.

peter.coombe 01-09-2020 04:10 PM

I have used the bridge doctor to save what were basically wrecks. Last resort option, but it works and guitars that were heading for scrap wood are now making sound, and the customers are very happy. One customer told me it improved the sound, but I have no idea what difference it made. One guitar was wrecked by an airliner, the other had a nasty cross grain break in the top and broken X brace. For the latter repair I got a big hug from a nice young lady who apparently had been doing the rounds of repair places with no success. Was worth it.

mirwa 01-09-2020 06:21 PM

Bridge doctors are IMO a stop gap product for guitar techs, most luthiers deal with the root problem instead.

A guitar with a bridge doctor fitted is not a deal breaker, I would however have it looked at after purchasing and have it removed and fixed properly (my interpretation of properly)

Steve

peter.coombe 01-09-2020 08:04 PM

Quote:

I would however have it looked at after purchasing and have it removed and fixed properly
Yes well sometimes the only "proper" fix is a top replacement that would cost way more than what the guitar was worth. Sentimental value is sometimes high and top replacement would pretty much destroy much of that as well. A bridge doctor at least is a viable option to save something that would otherwise be cactus. These are very practical considerations, one cannot always implement what might be ideal and "proper".

John Arnold 01-09-2020 09:44 PM

Most any problem that a bridge doctor would help can be repaired without replacing the top. There are methods to strengthen the top and/or bracing that can be accomplished through the soundhole. I have repaired several that had been deemed unrepairable by others. This does not mean an oversize bridgeplate, which can adversely affect the sound.

Neil K Walk 01-10-2020 06:31 AM

Quote:

Originally Posted by Troll (Post 6260329)
Disregard....30 minutes of research has told me all I need to know. Iíll pass on this one. Thanks anyway, go on with your day😎

Good choice. On a student guitar I'd say go for it, but for something of value it's essentially extra weight. IME the more lightly built the guitar the clearer the tone. The BD is essentially extra weight that reminds me of how we used to shore up leaks on wooden ships.

Personally, I'd be interested to see if there were a way to redesign the BD so that it wasn't so hefty. I've seen independent luthiers follow similar concepts with carbon fiber bracing running from the neck block to the inside of the waist to counter tortional stress at the neck joint. The BD does nothing to address a degrading neck angle; it merely immobilizes the bridge.

ChrisN 01-10-2020 12:20 PM

I've said many times, many ways, that I love my BD install on my '70s Japanese OM (Matsumoku via Conn) student guitar. Had developed a belly in front of the soundhole and the lower bout was pulled up, thus angling the bridge, resulting high action even with a too-low saddle.

The guitar was gradually, but easily, brought into alignment with the BD, though it did also still need some wood taken from the heel to bring the action down with a new saddle. No belly, flat bridge, flat lower bout - looks like new with 4/64 on the big E. Required a tweak on the adjuster to get the tone just right, but the guitar's like new again.

peter.coombe 01-10-2020 08:25 PM

Quote:

Most any problem that a bridge doctor would help can be repaired without replacing the top. There are methods to strengthen the top and/or bracing that can be accomplished through the soundhole. I have repaired several that had been deemed unrepairable by others. This does not mean an oversize bridgeplate, which can adversely affect the sound.
So John, what would you do with an inexpensive Japanese guitar with ~ 6cm break across the grain in the top. The guitar is unplayable, but has great sentimental value to the owner. The break is angled off from the bass end of the bridge. Looking inside with a mirror, the X brace has been broken under the treble end of the bridge and repaired before, but there is oodles of glue that looks like Titebond all over the brace and on the top around the brace and on the bridge plate and under the break visible on the top. So much glue that it would be impossible to glue anything near it without a major glue removal effort. Difficult and very time consuming ($s) to do through the sound hole.

mirwa 01-10-2020 09:57 PM

Quote:

Originally Posted by peter.coombe (Post 6261854)
So John, what would you do with an inexpensive Japanese guitar with ~ 6cm break across the grain in the top. The guitar is unplayable, but has great sentimental value to the owner. The break is angled off from the bass end of the bridge. Looking inside with a mirror, the X brace has been broken under the treble end of the bridge and repaired before, but there is oodles of glue that looks like Titebond all over the brace and on the top around the brace and on the bridge plate and under the break visible on the top. So much glue that it would be impossible to glue anything near it without a major glue removal effort. Difficult and very time consuming ($s) to do through the sound hole.

Peter, I have respect for your work and I have seen your mandolins, but, I would not use a bridge doctor to fix whats described in your scenario, not ever.

A bridge doctor is a device aimed at guitar techs IMO who do little to no luthery work.

Steve

peter.coombe 01-10-2020 10:30 PM

Ok, I am not trying to start an argument, just curious as to what others would do and maybe learn something. So what would you do that is not going to cost the customer more than what the guitar is worth (not much)?

In this case I was first presented with the guitar by the owner's friend and I sent it back with the message to get it to a specialist guitar repair person, which I am not. What I saw with the mirror was a god awful mess. So I declined. Soon later the owner returned and told me she had already been to many guitar repair places and all had said they could not fix it. I then got a pleading please, please try and fix it so I caved.

mirwa 01-11-2020 12:23 AM

If the internal braces are glued and functional but messy I would leave it / them alone.

If the internal braces are glued and not functional ie, glue creep is apparent or weakness etc, I would steam said brace or braces clean and reglue them.

Any crack going against the grain can be glued with a cleat or cleats sufficiently, in 20 odd years I am yet to have come across one that was so bad cleating did not fix.

Bridge doctors are there to reduce bridge rotation, the offset is the stiffening of the top, the added mass to the bridge area and reduced tone / responsiveness of the guitar, I wont use the term repair bridge rotation, many ways exist to permanently repair rotation and each method is really dependant on the guitar itself.

The cheapest i have ever fixed a guitar that had excessive bridge rotation was $35 which is my minimum charge and in that scenario i added a brace, but that is the difference IMO between a guitar tech and a luthier, a guitar tech sets up guitars and typically when confronted with a "repair" will purchase a ready made product targeting said issue, Eg, bridge doctor, truss rod rescue kit, premade bridges, premade braces, replacement fretboards preslotted and so forth, a luthier identifies the weakness in a design and crafts a repair specific to that instrument and its nuances

Steve

peter.coombe 01-11-2020 02:03 AM

Thank you.

The braces were messy but glued and functional as far as I could tell and were left alone. Gluing a cleat or any other reinforcement was not possible without cleaning up all that excess glue. Gobs of glue from the brace repair was already covering the area under the break. I would not really call it a crack, it was a break extending right through the top close to 90deg across the grain. From memory, it extended from just under the bridge plate, under the X brace and right out the other side of the X. Would not surprise me if it was actually much bigger than what I could see.

The owner told me she had been trying to get it fixed for more than 10 years. I don't claim to have "fixed" it, after all the top is still broken, but at least it is playable and sounded surprisingly good. I don't think I would have been able to fix it properly without taking the back off. Maybe someone expert at poking around through the soundhole might manage it, but I can't. The owner was fully informed and extremely happy and that is what really counts.

thomasfelty 01-11-2020 12:10 PM

I have used Bridge Doctors on a few instruments to make playable for people who didn't want to have new tops put on. I also did neck resets on those guitars. When I installed the bridge doctor I did it with only enough tension to keep the dowel in place so under pressure it would pretty much prevent the bridge from distorting the top. The neck reset was to keep the action playable. Every guitar I fixed for people that way made them happy to have the guitar playable again. As far as sound goes I couldn't tell you if it made their guitars sound as good when they first purchased them or not.


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