JLD Bridge Doctor - Stewart MacDonald catalogue

[Thermionik]

Has anyone here tried the 'JLD Bridge Doctor' (I've seen it at the Stewart MacDonald guitar tools site) to cure a bellied soundboard on a flat-top. Was it the screw-mount or the brass-pin-mount, and what effect did it have on the tone.

 

I know it wouldn't be on a Gibson - but you may have used it on a cheaper guitar..... I only ask because I just picked up an old Hohner dreadnaught (sic) and the top is slightly bellied, just enough to make the intonation a few cents out. Not an expensive guitar even in mint condition, but a nice old player nonetheless, and I am wondering if anybody has used said Bridge Doctor - because I will hack one up myself if the reports are good!

[littlejohnny]

Hi,

 

I used the brass pin mount on my '65 Epiphone Cabellero. It helped to cure the bellied top quite well. On a cheaper guitar i would recommand the permanent installation, because most of the effect will go away when you deinstall the bridge doctor. And the brass pin mount bridge doctor was no permanent solution for me. Bad break angle, because of that no good tone, doesn't look that good too.

 

hope that helps a little.

[ksdaddy]

I made my own back in '94 or so. I bought a Suzuki 12 string and the top was distorted quite badly. I've never had a bridge doctor in hand but I stole the concept. I did it because otherwise the guitar would have imploded. It sounded fine after the block was installed; no idea how it would have sounded without it because as stated, it would have imploded with 12 strings at full tension.

 

If you have a trash guitar and want to try it, go ahead, but man..... I see it as a last ditch effort. First I would back up and ask if maybe the bridge plate needs to be replaced... or maybe there are some cracked braces or something... ANYTHING short of welding a 2x4 under the top.

 

As to the Hohner being off on intonation, wouldst thou prefer to relocate the saddle?

 

Remember, always take the least intrusive method to get the job done.

[Thermionik]

I had considered shifting the bridge, as ksd says - but the belly shape suggests two things to me:

[1] the shifted location would be up the belly a tad, which might cause both action and sticking issues.

[2] the bellying is not too bad, and since it is causing the problem - rectifying it seems the logical way.

 

Suprisingly nicely finished inside, the bracing is very like I remember the early Martin 'X' bracing - with two main braces running in an "X" from the upper bouts to the lower bouts. The "X" crosses just between the sound hole and the bridge but nearer to the sound-hole (maybe an inch back), there is a sturdy cross-ways brace just above the sound-hole across the upper bout, and several smaller braces at the same angle as the 'X' bracing, and two good sized braces running diagonally at a more shallow angle across the bottom bout. Not only that Martin-like pattern - but scalloped ends and some shaping in the middle of the bracing suggests attention to the sound produced was quite good.

 

So I thought first off, lighter tension might do it, but having had a good inspection with the light and dentist mirror and finding all the bracing still glued fast and no cracks or other issues, I am thinking, since it clearly took a long time to belly this far, so maybe some active un-bellying might be needed, whereby I could very gradually apply progressively more correction in very small steps over several months or more.

 

I have only heard it with some very old, very tarnished strings, and it was rather nice - so I am going to keep it as a player - but I wonder if I am perhaps being over ambitious wanting to correct the belly it has developed.....

 

So (and this is especially aimed at ksd.....) if I follow the design of the JLD Screw-mount, I am wondering if this might reduce the belly somewhat without either looking too naff or making the tone suffer too much. ksd and anybody else who has been down these roads - your comments would be most helpful.

[retrorod]

I ordered the Bridge Doc from Stew-Mac. It is currently on my 40's LG3 (brass pin version-didn't want to drill a whole through the bridge). I can,t say there were any REAL exciting changes in tone (to my ears). It DID take some bellying out of the top and improved the action slightly (which was the goal) as it sounded damn fine as it was.

I don,t like the aesthetics of those brass pins. The wholes they drill are barely big enought to get the ball-end of a 'healthy guage' string through also. It does affect the break angle as mentioned previously and with a low saddle could lead to some buzzing issues. I am sure the BD has its merits on a case to case basis....In my case, I think that a neck set is in order for optimum playability! Hope this helps...RRod

[Thermionik]

retrorod - thanks for that, it wasn't an improvement in tone I was expecting, rather just wondering if the tone suffered at all. Seems to me that twisting the flat-top and thus 'tightening' it up, might just strangle the tone or something. I am reassured by your comments, but.....

 

I am still in two minds which way to go. With lighter gauge EB Earthwoods on it still sounds good and the intonation is playable 'in key', though modulate too far away and it starts to jangle to my ears. The lower tension may allow it to settle back, or may stop it worsening, and I guess all our bellies start to grow as we get on in life, and that old Hohner is no different.....

 

So - I will leave it be for now, and see how it goes, but I think in the long run, I will be 'cobbling together' a Bridge Doctor and fitting it - just to flatten that flat-top, if nothing else.