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I'm planning to build a small jumbo for my next build. I have the Scott Antes plans for a "similar to Gibson jumbo model", which I think equates to a J-185. I am reducing the size of the lower bout by 0.5".

It looks to me that the bracing of the back at the lower bout is a bit hefty. The plans call for these braces to be 3/4" x 3/4". Can't I reduce the size of these braces a bit? Any suggestions for the height and width on these braces?
Thanks,
Steve

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

My understanding of the Antes plans is that they tend to be over-braced. That was my experience with the parole plans.

Steve

Depends on what you're going for. With braces that size, I assume the intent is a non-live back, in which case there's no tonal improvement to be made by changing it. But if you just want to lighten it up some without changing the stiffness, you could cut the width in half and multiply the height by cube root of 2, giving 3/8" wide by just over 15/16" tall.

Does anyone have the OLF small jumbo plans? I'm wondering how those brace dimensions compare to the Antes jumbo plans...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I'd be interested in those plans as well.

I'll check my plans in the morning, and what I used on the SJ on my bench (can't remember!).

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

The Antes and the OLF SJ plans are considered overbraced here - we use the OLF body outline and disregard the rest of the plans. The usual sizes used here for bracing in red spruce is 1/2" x 1/4" for #1 and #2, and 5/8" x 5/16" for #3 and #4, with the top bracing all 1/4", and X 0.600", tone bars 0.500", fingers 0.250", and UTB 5/8" x 3/8".

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For the times they are a changin'

- Bob Dylan

I've never seen the plans but have wanted to have a look. Plans are like recipes- open to interpretation. After all what's the fun in building something that you can't put your own spin on it? I can draw my own plans but it would be interesting to have a common starting point from member contributions here and see where it winds up. Right now I only build my own custom shape which is somewhere between an 00 and an OM and doesn't fit any cases snug enough for my liking. Am I wrong to assume that this shape would fit relatively snugly in a standard SJ case (if they even make those)? Or am I better off following the profile of a more standard design for the profile (which would more likely be a Jumbo) and sorting the rest out myself? Eventually I'd like to find a supplier that can fill my custom case needs at a reasonable price but for now I'd like my next shape to have more readily available/affordable options for cases. I have other more pressing needs to spend money on at the moment than cases.

The OLF SJ will fit an OLF SJ case from Ameritage, while most other generic SJ's - all variations on Gibson's shape - will fit some of the other cases from Canadian, TKL, etc. We prefer the Hiscox Pro II cases - for the wide range of guitars fitted, excellent protection, and the lighter weight construction that is kind to ageing shoulders. Lately, the best prices have been from Musician's Friend (we look for the frequent 15% off/free ship deals), but Elderly usually gets our business because they work so hard on solving other problems for us, such as finding cases to fit vintage instruments and other snipe chases. Mr. Dave Nichols of Custom Pearl Inlay was in the past a dealer for Hiscox and may have pricing for OEMS as well.

The Hiscox Pro II GAD will take any SJ we've had in the door, including the oddly shaped Omega, the few Olsens we see without Calton cases already fitted, and the OLF SJ, as well as a wide range of 12 and 14 fret dreadnaughts, Gibson wide-waisted jumbos (J-45/50 slope and square shoulder), and some of the grand auditorium shapes such as Taylor.

I am not sure if Mr. Kragenbrink has any OLF SJ plan copies in stock, but I would suggest you start there, as sales support this community and the ever-present server bill. If you are unable to source a set of OLF SJ plans, I am sure we can arrange a loan of the shop's set for you to inspect. CAD Guitar Plans (www.cadguitarplans.com) has a J-185 plan that looks fairly close to Gibson practice, but again - we used the OLF SJ body outline and developed the other details from the various resources available online, such as the Gibson Bracing LIbrary on UMGF.

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For the times they are a changin'

- Bob Dylan

I think any plans that I've ever seen are all over braced. But anyway I like the wide lower bout back braces and have been using those a lot lately. I aim for a live back on most of the guitars I make these days and go for 3/4 X 3/8 in the center. At the edges due to the arch it's more like 1/4 then I scallop that down to 1/8th starting 2 1/2in back and tuck it. At that dimension the braes have a lot of flex in them. 3/4 x 3/4 would be solid.

For a Jumbo though I might go a bit taller on the back braces.

Thanks Woodie! Thanks the kind of information on the bracing I was looking for...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Steve, FWIW. I am just getting ready to start a J-185 style myself and I plan to have my lower bout back braces wide and low ( 3/4" x 1/4"). I have used this size in several of my dreads and like the resulting sound. This guitar will have an EIR B/S and a Bear Claw Sitka top.

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"I've been had again"
Tim Benware
Creedmoor, NC

Thanks Tim, Maybe I need to drop by and check out your build... I'm planning on a Florentine cutaway and to put in my first arm bevel on this one. I figured the SJ shape was conducive to a bevel. Should be fun...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I am leveling the frets on a 1953 Gibson CF-100e style (Florentine cutaway, yuk!) today. Haven't done a arm bevel yet, interested in that. We should definitely get together it's been a while.

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"I've been had again"
Tim Benware
Creedmoor, NC

I prefer a Florentine cutaway but not that one!

I guess this is getting off topic...

Tim - You don't like Florentines? ...or is it that guitar? It appears to be knock off... How's this one Joey?

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Pretty sweet looking guitar, Tim. I’ll have to try that bracing on next guitar I’m making.
Ed

Tim - I am sorry. I didn't recognize your logo on that CF-100 headstock. That's your build. I didn't mean to sound like I was bashing the guitar. I just noticed that it was not a Gibson. It actually looks quite nice. I thought you were doing a refret for someone. Why did you say "yuk"? I always kinda liked the look of the CF-100...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Am I understanding this correctly?3/4 wide by 1/4 tall ?

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Say what you do, Do what you say.

Yes. Ends tapered similarly to the taller/thinner braces.

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"I've been had again"
Tim Benware
Creedmoor, NC

I didn't take it as bashing (I think I know you better than that:)). I like the look of the Florentine but not the building of one. My customer requested the CF100 knock-off.

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"I've been had again"
Tim Benware
Creedmoor, NC

Tim - I like the CF-100 and you did a great job with it. I've never seen a plan for one. Do you have one or maybe you traced one out... Yeah, floretines are trouble, but they sure look cool...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Traced it out and took measurements off an original '53. I have them in my files and you're welcome to them if you'd like.

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"I've been had again"
Tim Benware
Creedmoor, NC

Here are the brace sizes from the OLF SJ plans:

X - 5/16 x 3/4
Tone bars - 1/4 x 3/4
Finger - 1/4 x 3/4
UTB - 7/16 x 5/8

Lower bout - 1/4 x 3/4
Upper & waist - 1/4 x 1/2

Alex

_________________
"Indecision is the key to flexibility" .... Bumper sticker

Interesting... Here are the brace dimensions from the Antes Jumbo Model. They are heftier than the OLF SJ. (Also - note that the OLF back lower bout braces are the same as Tim Benware suggested...).

X - 5/16 x 11/16
Tone bars - 1/4 x 5/8
Finger - 1/4 x 3/8
UTB - 1/2 x 3/4

Lower bout - 3/4 x 3/4
Upper & waist - 5/16 x 5/8

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com