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Hi all,

I am bracing up my first top and thought I would get some input concerning which surfaces of the bridge plate to glue (and why do it one way or another).

I have seen some put the bridge plate right up against the x brace. Others say to leave a small gap (Kinkead book). I tend to want it right up against the x brace. If I put it against the x brace, should I put glue on the sides of the bridge plate to glue it directly to the x?

Thanks!
Peter

Really? I wonder why anyone would do that.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

What would be the disadvantages of the gap? I just finished bracing #3 based on the Kinkead book and all have had the gap based on those plans. #4 is in the works and will be my "good" guitar for a while. If there is something to be gained by changing this I'd like to learn.

Donald

I butt and bevel the edges, all of them, to about 45ish degrees.

I leave a gap but I don't think it really matters either way. I glue all the flat grafts on first, I imagine it would be easier to but it up against an already glued x-brace. Tucking it in would certainly make it more secure but then maybe that is what Kinkead is after, if the plate gets chewed up and needs to be replaced it would be easier. But I don't know sure sure.

Todd, that's a bit of a drastic reasoning. Everything in guitar building is about finding the good balance beween two extremes. It's not because a small gap may be acceptable that there is suddenly no need for a bridgeplate whatsoever.

I for myself don't care too much about tucking braces between one-another, or bridgeplate for that matter.

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I'd suggest that the plate and the X together form a platform for the bridge, and that introducing a place where that platform is broken and the top can distort upwards may lead to the bridge lifting off adjacent to the gap. How big is the gap in those plans?

I generally agree that as a convention of discussion, the person who goes against tradition ought to be the first to put forth a reason.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I believe Santa Cruz guitars were originally built with a gap between the bridge plate and the x-brace, and they may still do it on some guitars. I heard an interview with Richard Hoover where he mentioned that he believed there were benefits to this.

I think the idea behind tucked braces and bridge plates is that the braces would be more of one unit, but also, I think it's to avoid loose braces in the areas where the braces have the least height. I know many vintage gibsons didn't even tuck the back braces or X braces into the kerfing, and you often find the braces are loose at those points. Martin tucked the bridge plates underneath the X arms up until the late 40's, but then they switched to a butted bridge plate. I think that there may be tonal benefits to the tucked bridge plate, just my belief, as those old martins sounded pretty good. I do think it is important not to notch the bridge plate too far into the X-brace, as to allow enough gluing surface for the notched X-brace. Same goes for getting a good tight joint between the notch and the bridge plate, as this will likely strengthen that areas glue joint. Some of the Martins had a bit of a loose fitting joint in that area and I think that is why the X-brace would occasionally become loose in the bridge plate area, as hide glue doesn't make a good joint filler.

Great responses, everyone. I would love to hear more. I figured there were some different ways to approach this issue.

So far, I am gathering a general consensus around the idea of a bridge plate that is more directly connected to the x-brace may form a more unified bridge bracing system.

Peter

Indeed the size of the gap is important to know here.

For myself, since the wings of the bridge (which has to be considered a pretty large brace itself) overlap the entire bridgeplate/brace joint areas, I feel the small gap there may be between the bridgeplate and the braces (1/16'' max) is insignificant. The 'platform' isn't broken. Actually, the way I see things, the entire bridge area should be considered a single unit on its own, including the bridge.

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I may not have made my point clear when I asked the logic for butting the bridge plate, and for that I apologize. The only reason I am going against tradition is because I didn't know it was tradition until this thread. The Kinkead book said do it that way and I did, no further logic. I've built 2 and 1/3 guitars and the only thing I'm sure of about guitar building at this point is chisels will draw blood. I didn't mean to suggest Todd is wrong, I don't know enough to take a stance. I just wanted further input to increase my knowledge base. Is it a sound issue, a structural issue, etc...

Again, sorry if I offended anyone or used poor etiquette, I'm still learning. Thanks for all the input.

Donald

Donald,

I am sure about the chisels and blood thing too! I don't think anyone was mad at you or that you violated any ethic. I think they were just asking for a clear explanation for the rationale behind leaving a gap if someone could provide it. The Kinkead book does not provide it, or I would have provided his rationale.

Peter