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Hello,

I'm in the process of working on a new parlor build based on the Antes plan from LMI. I've read here that two things often happen with this plan:

1) The braces are put on backward.
2) Over braced

I'm trying to avoid that if possible.

My setup:
1) Sitka Spruce top thicknessed to 2.5mm
2) Sitka bracing. All bracing (with the exception of the upper brace) is ~7mm wide. The plan called for 8, I took it down to 7.
3) All brace ends are shaped down to 2mm where they go through the kerf. The finger braces go down to nothing

The height of each brace and a pic is below.

Questions:
1) Should I take more off the bracing and if so where?
2) Are the braces on backward?

Overview of braces:


X-Brace Height (Center) - ~14mm


X-Brace Height (Node) - 11mm


Tonebar (X-brace side peak) - 12mm


Tonebar (valley) - 5mm


Tonebar (edge side peak) - 10mm


Upper Transverse brace - 11mm


If any additional pics or details will help, just let me know.

Thanks!
Brad

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I'd take and re-shape those (X and tone bar) into a peaked scallop at to about 2" from the perimeter and intersection. The height looks OK but the shape should be more triangular, perhaps 1/8" or even less at the top. The finger braces are merely cross grain crack preventers. So those can be substantially reduced in size as well. Upper leg "X" looks OK. Of course without having it in hand its impossible to determine tap tone -- but I have no doubt that its currently way over braced.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Most folk use a triangle shaped brace profile, not rectangular like that.

I've built a bunch of size 2's from those plans with mods. Braces are 1/4". Tops are deflection tested but usually wind up 0.96-0.110.

Here is a build sequence for one that shows the bracing. I splay my X about 93 degrees and lengthen my bridge to about 6.5" to catch the corners of the X.

http://kennedyguitars.com/building-process.html

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OK, so that I'm sure before I get out the chisel.

The highlighted areas should go up to points with 1/8" surface on top (at most). Correct?

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Thanks! Are we talking about the same thing as Ken (see the pic above) or do you mean tipping the plane on a 45 and pointing the tops of the braces? I did that for the upper transverse and the back braces, but did not for the X or the tone bars.

Thanks!
Brad

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Yes -- take a look at Terrence's photo album above exactly what I am describing.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Even though I have several Antes plans, I am not sure I have ever followed one completely. I have always built my guitars lighter.
I have a Parlor plan drawn by Rick Micheletti that is a 1906 Martin Parlor. It is very similar to the bracing, and size, of my 1921 0-18. The 0-18 does handle extra light strings.
The X braces are 1/4" wide by 1/2" tall, scalloped with a radius on the top
The single tone bar is 1/4" x 3/8" scalloped and tapered sides
Finger braces are 3/16" x 3/8" tapered sides
Even the transverse brace is 1/4". Even though that is fairly light it is also what was used on my '27 00
The X intersection for the 12 fret design is at 10" which looks lower than yours.

That is a bit of a different look than your plans. Maybe somewhere in between would work?

Tim

What they said...

Thanks, Everyone. I'll take another crack at it using Terrence's pic as a reference.

Thanks!
Brad

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This will help a ton. Thanks!

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As you shave the braces, stop, hang the guitar on a finger through the soundhole, and tap. The braces, the bridge, everywhere. As you shave the braces, the tone should drop and the sustain should increase.

Now the problem is, when do you stop? If I knew the answer, I'd be selling my guitars for a lot more money

Good luck

Steve

One more thing. Taper the edges of your center seam patch, as well as the bridge plate. It's a little guitar. Every ounce counts.

Steve

Here's the last one I did.


Top was .101 ish and the x and tone bar started out as 1/4" x 1/2" . That's fairly standard for mine and there is very little belly or top distortion with medium strings.

Great little guitars! I've built 4 for myself and I still don't own one.

Do you have a strong opinion one way or the other on putting the bottom part of the X brace through the kerfing? It looks like you didn't. I was planning to but to be honest I'm just following Robert O Brien's video. I don't have a strong reason or experience one way or the other.

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If you mean Brad, letting the X and/or tone bare into the side and linings, no, I don't ever do it. I have only done one guitar with the X let into the sides. It sounded great....... if you pounded the crap out of it with a heavy flat pick.

I think the only advantage of letting in is the lower X is less likely to delaminate from the top. IMHO, not letting in allows for more free movement of the top. (think speaker cone). The one that I did do and wasn't happy with has scared me away from that approach. I think you will find that most builders don't, but not all. But what do I know.

Cheers!

Just out of curiosity what are the back and sides?

Bocote!

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Based on Don Teeter's comment years ago -- "the only thing tucking the bridge plate or braces under one another does is piss off the repair persons years down the road" might be true, but I still don't do it. I do let the upper bout "X" into the linings as well as all the back braces. I keep the tone bar and lower bout "X" clear of the linings. Taylor"s are clear plus a routed channel to help the top move freely.

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Ken Cierp

http://www.kennethmichaelguitars.com/

OK, here is what I have so far. I would appreciate any feedback on where to modify further. There are before and after sound files linked at the bottom of the post.

Overview of braces:


X-Brace Height (Center) - still ~14mm


X-Brace Height (Valley) - now 5mm


X-Brace Height (Node) - now 8mm


Tonebar (X-brace side peak) - now 7mm


Tonebar (valley) - still 5mm


Tonebar (edge side peak) - now 8mm


Upper Transverse brace - still 11mm


Sounds files. Tap 1 below tonebar, tap 2 above tonebar, tap 3 on bridge plate, tap 4 below X Brace intersection.

Before
https://soundcloud.com/tofu-x-labs/ante ... tap-before

After
https://soundcloud.com/tofu-x-labs/ante ... -tap-after

Thanks!
Brad

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This is some good advice! Not that I think I can add much, but I have found it easiest to do an initial scalloping and tapering before profiling the braces, then fine tuning the scallop and taper as necessary to voice. A small bracing plane is very useful for the profiling work - I made my own plane as one of the little projects inflicted on us students here, but there are small planes available commercially, such as the Lie-Nielsen violin plane, or from the OLF's own Mr. Stephen Boone.

Here is the link to Mr. Boone's plane making video, which is a nice treatment of the process. Mine was similar, but with a lignum sole and a replacement Ibex blade versus shopmade.

https://www.youtube.com/watch?v=rwyKe3iOb8Y

One thing that was emphasized by the boss (emphasis as in "cut off all that bracing and start over.") was the need to keep the curves of the tapers and scallops smooth and moderate in terms of change in depth. A catenary-like curve - think suspension bridge - is a smooth curve that avoids 'elbows' in the stiffness curve. I think of it as that suspension bridge-like shape as opposed to the profile that looks like two widely separated ant hills on a flat stretch of ground.

I am not sure if it's still available here on OLF, but the boss saved a copy of an OLF-sponsored lecture by Mr. Ervin Somoygi that do a good job of illustrating how minor changes in brace height have major impacts on stiffness, and the case for smooth, progressive curves. Very interesting video!

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I'm wondering why you didn't extend the bridge plate all the way to the X braces, Brad? It seems that stopping short would create a stress riser that may cause cracks to start at that point, with the rotational pull of the bridge, under tension. Or I might just be wrong, as happens often!

Alex

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Good question. The honest answer is that I bought a few pre-cut bridge plates from RC and that is the width they come in. I considered grabbing a piece of maple from the local supplier and cutting another one. I decided against it, but I may pay for it in the future. Thanks for the details about why stopping short might be an issue. That is helpful going forward!

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Looking better. I agree transitions are a little abrupt but I'd go with what you have, record all the specs, see how it turns out and tweak the next one accordingly.

As mentioned I'd tuck the upper X and UTB but feather the lower stuff to the edge of the linings.

Let us know how you like it.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Thanks, Terence! I have archived the specs. I'm thinking of adding the soundhole bracing as well, which shouldn't take but just a few minutes.

So that I'm 100% sure what we are talking about. In the pic below you can see both the top and bottom of the X brace. The red boxes I was planning to tuck into the lining. The green boxes go down to zero a bit before the edge of the soundboard. Look correct?



Thanks!
Brad

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I"m not Terence but that is what I do and I'm sure that is what he means. I would feather the finger braces and tone bar out to zero too.

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Bryan Bear PMoMC

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