Gibson J185 back brace heights--Anyone have the answer?

[tippie53]

Actually Dan 3/8 would be more than heavy enough. Wider isn't always stronger , the stiffness is in the height. Ken points out about the braces at 1/4 inch wide , I think he may be right . You will not gain anything by overbracing , in fact you can loose tone .

[Dan Bombliss]

I'm not claiming I'm deliberately over bracing, I already glued the 3/4x3/4" braces down, according to the LMI plans I purchased. and all I can do now is cut the height.

[Darryl Young]

With a little heat you can remove the braces from the back. Thin the braces, clean the glue from the back, and re-glue braces that have the correct thickness.

[Jim_H]

Dan,

Who drew the plan?

I'm just curious. I don't think LMI draws the plans, or even commissions them. Much like the books and DVD's they sell, I don't think they are really responsible for the content of them.

I have a whole bunch of plans I've bought from various places. I'm currently building a dread using the Dan McRostie plan I got from StewMac. I'm mainly just using the plan as a guideline.

I kinda learned from experience the hard way that (at least some) plans are not intended to be followed to the letter . I recently re-topped an OM/OOO, and followed the Micheal Dale Pane OM plan for this. Using his dimensions the braces were really really heavy. Thankfully, before I closed the top up, I took it down to Rick's shop and he gave me some tips on lightening it up. I got lucky. That guitar actually sounds pretty decent now, but if I had closed up the top before I talked to Rick I'd probably be a pretty unhappy dude. =)

[Dan Bombliss]

Well, when you're ripping your own braces from scratch stock, you kind of need to rely on your plans to at least have accurate dimensions. How else are you suppose to guestimate that with out experience? I can honestly say I'm a bit flustered. I haven't done a J185 yet, so I can't really go by experience. And the number of OMs and dreads I've done don't help me much here, seeing how small OM braces are.

If they were premade braces I could see not going by the plan being an option, but you can't expect to do that with a new body build, and jump in blind with out dimensions.

[Dan Bombliss]

I took a peak at the plans it says Scott E Antes, 5-15-09. If you see the plans for this by S Antes, stay away from them. I already had issues with out the widths of the back braces being in there, I mean it was an easy enough fix, but still frustrating to have more than one contradiction in a plan that I payed real money for.

[Jim_H]

Something else I learned (the hard way) about printed plans, is that they are very rarely accurate for size. I'm sure the original was fine, but digital copy machines don't do a good job of accurately sizing them and they get shrunk after repeated copies.

The fretboard on my MacRostie Dread plan is almost 1/4" shorter than the actual fretboard if made to the proper scale. Fortunately, the actual measurements are provided.

This is not unique to Scotts plans, or even guitar plans. Any time you make a digital copy of something it's almost certainly going to get munged. It's not noticeable when making copies of 8.5 x 11 documents, but when when making copies of large blueprints/plans, they are almost always going to be either too big or too small (usually too small by my estimation).

Always go by the measurements and don't trust the scale of the plans.

[Dan Bombliss]

I don't actually use any blueprints outside of my former instructors plans now anyhow. The school I attended for construction and repair had the all of the blue prints for basically any variation of bracing, per body style, sloped shoulder or not for dreads, and any scale lenght. Basically a mix and match for the most part. Although, jumbo isn't offered, it goes parlor to dread. These are all insanely accurate amazing plans for only 5 bucks each. All drawn up and printed by David Vincent, the instructor for the acoustic guitar construction class. All the measurements are printed direct form the original digital rendering of the CAD program, and measured when printed to be sure of accuracy seeing as how the students at that school will be using them to measure directly off.

So, the one set of plans that I buy that is not form there, is a completely bogus set as far as information goes, and I can't really express my disgust for inaccuracy. What good are plans if you already have a template, already have an outside mold to hand bend to, and you can't rely on the dimensions listed? I'd might as well use them to get a fire started, they'd might actually have a purpose that way.

-Dan

[Dan Bombliss]

With a little heat you can remove the braces from the back. Thin the braces, clean the glue from the back, and re-glue braces that have the correct thickness.

The spruce back graft has already been notched to 3/4". I'm going to go 1/2" tall by 3/4" wide and I'm sure it will work. Early Martins and Gibsons were popular for doing the short fat bracing on the back, so those dimensions are not too uncommon from my understanding. Still stewmac dread kits are supplied with 2 braces of those dimensions and dreads are still commonly built like that. I'm confident those specs will work for these 2 guitars this time.

-Dan

[Jim_H]

Well, I don't disagree that the plans are of little use if you already have a form and bracing locations.

For me, they provide a nice visual reference for how things go together. The measurements (expressed as numerical values) can be helpful as well. You just have to be careful not to take measurements from the drawings, or use them as templates unless you are sure they are correct.