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I recently purchased the new J-45 plans from Stew-Mac. I found something that gives me pause. The two transverse tone bars going out from the x-brace have a pronounced radius to them, moreso than on any other blueprint I have. However, The X-braces are almost completely flat. To me this seems a little hinky. Does this seem wierd to anyone else?
Thanks for any input

Define "hinky"?

Are you saying they would sell plans that they knew were bad or not carefully done?
I doubt it...

So let's ask the question...have you ever looked inside a J-45, of the year of the guitar was measured for the drawing?

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

No suggestion of any wrongdoing of any sort implied.
I simply wonder about having the x-braces and the tone bars at a different radius. For example, if you buy a set of pre-made stew-mac dreadnaught braces, the x and t-bars match each other in their radius (although they are a much smaller radius than the stew-mac "herringbone" blueprints). To me that makes sense, while having different radii (sp?) seems counterintuitive. And no, I've never had a chance to measure the real deal, however it's likely safe to assume that any 50's J-45 that has had strings on it for 50 some odd years will have some top warpage, making it hard to know exactly what it looked like the day it first left the factory.
Thanks
"Hinky" ...anything that makes me go hmmm...

Med buddy welcome to the OLF!

Make them all the same radius.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Straight from the horses mouth!
Wouldn't that be most fantastic!

Also spelled "hincky," "hinkty," etc. etc. Usual meaning is anywhere along the spectrum from worried to nervous to paranoid. The present usage is a bit different, but related.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Sorry to take so long to reply to this one I have been unusually busy and just saw this post.
I measured the guitar very carefully. Using a series of straight edges, and a tool with dial allowed me take the measurement directly over each leg of the x. This was done with the string tension off the guitar. The result is the x brace was indeed flat.
The lower braces were arched as shown.
The top is not a single radius, but a series of compounds. The upper bout being completely flat with no arch. The most pronounced arch being in the lower bout.
The guitar is extremely solid with very little distortion.

Hi!
Just to be perfectly clear, it was never my intention to state or imply that an error on the part of the plan illustrator was made.
However, I'm still a little confused. Do you guys think that the guitar looked like that when it was first made? It sounds like that shape could have been derived from time and string tension, pushing down in front of the bridge and pulling up behind it. Gibson's website boasts that j-45's have " a radiused top for better projection", at 25", I believe. Anyway, I chickened out and built my top with a constant radius in all braces, and used the prints for layout and dimensions.
I just wanted to make sure you know that I am not calling into question either your competence or your accuracy...

Hi,

You raise some good questions about what the braces might have been.
It would be difficult to guess just how the braces were when they left the factory. I also wonder how the design has changed recently and if it jibes with what they were doing in the 40's and 50's. I don't recall any info on Gibson using radius dishes back then, and the majority of older guitar I have looked at are compound radius on both the top and back plates.

I definitely did not take your post as an attack. And I am sure you know I could only measure what was there and post my results.

That being said, one could use a single radius (25') and make a great guitar. I hope you will post some pics of your build!

Michael Collins
www.collinsguitar.com

Good timing on this discussion because I also am building a J45 from a set of Michael's plans. I'll be putting a 25' on the top and a 15' on the back. That's why I made the dishes and I'll be putting the adjustable neck joint in it too. Nice drawings by the way Michael.

Were the old J45s built lighter then today? The plans have 1/4" X 1/2" back braces and my J45 which is about 9 years old has 5/16" X 5/8" back braces.