Update on using a Bridge Doc on D-25K Martin

[Rob Mercure]

Folks.

I hope I'm not clogging the board by starting a new thread on this but it is a segueway (sp?) from my original thread. So, as reported I installed the BD to correct bridge bellying over a month ago and since then I've let the guitar set mostly - playing as energy allowed - to really see what happened. When I installed since I wasn't sure how much tension to use I got the machine "tight" but didn't try to pull all of the belly out of the bridge. And it seemed to work well.

This morning I addressed it again since the results so far have been positive and benign and actually tightened the machine so that it is as tight as I would ever pull an adjustable truss rod which wound up taking almost all of the belly out. Immediately the guitar got noticably louder with much more pronounced treble - much more like the original sound before the instrument was broken in with that classic Koa brilliance that I love but which also highlights noise and mistakes. And one of the strings - the B - started creaking at the saddle (bone) when adjusted - no string creaked before (I loosened it and rubbed in a bit of pencil "lead" - I'll probably recontour it or make a new saddle later). Overall guitar was easier to play and louder but somehow lost a bit of the "richness" that comes from again and, again, was more like a factory new sound. Now some folks like that sound but for my tastes I prefer a guitar that sound played and "broken in." So I'll proably leave it again for a while and see if it changes but if not I might loosen the tension a wee little bit.

While I know that the BD manufacturers have their expenses to watch and if Stew-Mac is charging $30 for the machine then the maker is probably getting $15-20 from them but the overall cost of materials is low enough that I'd like them to provide an allen wrench that would allow adjustment while under tension and if anyone is expecting to install several of these it might be worth purchasing those bit drivers that use a bit of flexible cable between the handle and bit holder to allow easy adjustment. I don't have one of these but if I can't figure out how to cobble one up (any suggestions?) I may have to buy one.

New from the field.

Rob

[Len Biglin]

Rob I have not tried the BD but I use a flexy 1/4 socket extension for similar jobs , you can add the appropriate socket that fits the allen key , but you'll need to cut a straight bit off the allen key to use in the socket . Hope that makes sense, as I have not seen the BD .Len

[Ned Knepp]

Hi Rob,

When I've adjusted a BD, I loosened the strings to do it and made small adjustments. I think the small adjustments allow the face to return without fighting the BD very much. I wasn't thinking of using the BD to overcome the string tension so much as I was considering it reinforcement for the top. This may well be where you are getting the tight sound you noted. Our guitar's sound didn't change very much at all.

I would be a bit concerned that cranking it down as far as it will go may actually force the bridge to over rotate over time. That or it may induce a warp/curve into the dowel that may cause it to fail and allow the bridge to rotate forward again. I suppose that a lot depends upon how elastic your top is and how much movement is needed to return it to it's proper position.

Ned

[Jeffrey L. Suits]

This JLD tool came from James, the "J" of JLD, should be self explanatory, a gear, some stuff, & ingenuity: a way to adjust a JLD when the guitar's strung up, which IS the way to find the sweet spot. Hope it helps...

[Mike Kolb]

Now that is one slick lil' tool. Proof-positive that a picture really is worth a thousand words. I'll have one cobbled-up by the morning!

My only experience with the JLD bridge doctor was as an aid in converting a Breedlove nylon string guitar to a pin-loading steel-string. Whether it was actually needed or not is up for discussion, but it -along with a larger bridge plate- was some good insurance and (per the customer) really helped to "tighten up" the overall sound of the box.