Falcate braces - radiusing?

[gerryt]

Maybe it's the plethora of info in the books or my reading of them but nowhere can I find any mention of putting a radius on the underside of the falcate braces on the top. If there is one can someone give me a page reference please? If there's not am I to assume that the use of epoxy/carbon fibre and gluing the braces inside the radius dish is sufficient to impart the radius?

Thanks again.

[Dave M]

I take it you mean shaping the underside to fit the spherically arched top - as we do with the back braces.

At some point, and it may have been in this forum rather than in the book, Trevor has stated that the braces will happily sit down into the curve even though they are flat. I guess this is due to their curves in the horizontal plane.

Anyway I can confirm that they work fine without any shaping.

Cheers Dave

[gerryt]

Yep that was exactly what I meant Dave!

Ok so maybe the carbon fibre and epoxy helps with reducing the spring back? I'm thinking there would be no issue even to go ahead and radius the underside of the braces just for a belt and braces approach.....

[Trevor Gore]

The falcate braces aren't shaped on their side that glues to the soundboard. A better, more conforming surface is produced just by planing them flat. Spring-back hasn't ever been an issue for me.

[gerryt]

Thanks (again!) Trevor. It seems slightly counter intuitive to me having been making guitars the 'standard' way for a number of years that just gluing the braces in a radius dish imparts the said radius to the top. That said I'm having to change lots of things about the way I build guitars since getting the Books!

[Dave M]

I haven’t done this but I guess you could check the situation by laying the falcate braces in the radiused/dished workboard and checking for gaps with feeler gauges.

As you have suggested any small gaps will be filled with the epoxy.

Cheers Dave

[kiwigeo]

I haven’t done this but I guess you could check the situation by laying the falcate braces in the radiused/dished workboard and checking for gaps with feeler gauges.

I've done it both ways. Shaping the bottoms of the braces didn't make any difference to the end result. When you start shaping the braces you actually increase the risk of the brace bottom and top not having a nice close fit. As Trevor notes a flat brace bottom will always fit nice and snug against the top.

[gerryt]

Good to know that it's been done without incident Martin. I'm pretty confident in getting a good join between brace underside and top after sanding in the radius dish but I guess the curved braces could be a complication that I haven't experienced before.