Experimental Steel String Top Build
 

https://i.imgur.com/LQJJJl0l.jpg
I have long wondered if a steel string top with lattice braces only would work.
Having seen the Taylor V brace, it got me thinking about the addition of parallel braces to help with the pulling stress of the bridge, while loosening up the top to vibrate. The x joint on an x brace has a real stiffening effect on that whole area, I think.. Before I glued it on the frame, I added 2 braces the same size as the lattice braces, going from the bridge plate to the lower transverse brace, and let into that brace at the bottom. Forgot to take a pic of that. LOL
The large sound hole patch is to deaden the top above the lower transverse brace, hopefully concentrating as much string energy as possible in the main vibrating plate area. Muck like a classical guitar.The lattice braces to provide a stable yet light platform to encourage a more controlled vibration over the entire vibrating plate.
Well, that's the theory anyway. LOL. Won't know till I string it up, see how it sounds, and if the top is stable. Russ Parker

I'm curious to see what the braces parallel to the grain do to the top under tension.

Me too
 

I hope that the lattice bracing Compensates. Dave Wren voiced the same concern when I sent him a drawing of the plan. The lattice is uninterrupted, and the longitudinal braces are notched over top. But as I said I will see. Lol

A local builder here in Stockholm makes steel string guitars with lattice bracing and they sound just fine. Don’t know exactly how he does it but it’s definitely doable.

I'm not a builder, or an engineer, but I would have though that replacing one major X brace with a bunch of smaller ones would lead to a stiffer soundboard?
On top of that you're adding 2 more larger X braces at 45deg to the lattice which I would have though would increase the stiffness again.
Isn't this the exact opposite to what you want to achieve?

Questions
 

To Frankond. Thanks for that. I'l think on that idea more.
To Zandit75. The lattice bracing gives a stable , yet light platform. My X brace guitars with lattice bracing are by far, the best sounding guitars I have made so far. As I say, it is only theory till it has strings on it, but I hope it works. Lol.

Experimental Top Steel string
 

https://i.imgur.com/NeePXK9l.jpghttps://i.imgur.com/rG2rBPrl.jpg]https://i.imgur.com/Y77hjSGl.jpgBoxed up with hot hide glue, just in case top removal is req'd. same reason there is no binding on the top. lightly stained zebra wood body. A cherry neck showing the adjustable neck system. I am using Osmo PolyX hard oil wax finish.

Am I seeing this correctly that your top is actually two plys below the upper transverse brace? I'm theorizing but one would think this will make for a heavy, dense and quite stiff top in addition to the lattice structure, it may be very bright sounding and treble biased? I'll wait to see how it turns out for you and would be interested in reading your thoughts after its strung up. Beautiful set of Zebra wood BTW.

top
 

Hi Tim. You are correct. I added a full width sound hole patch to deaden that area, so to hopefully concentrate as much string energy as possible to the vibrating plate below the sound hole. I do this on my nylon string guitars and am happy with the results. but I'll see soon If I was right. LOL

Hi Russ,

Is there also another double layer of spruce that the lattice is glued to? I’ve seen (and used) cross grain sound hole patches but I’ve never seen one on the lower bout? That is what I was trying to refer to in my question above.

Top
 

Got you now. No, what you see is a ledge, routed around the top, thinning the top to loosen up the sound board, like a Taylor route only thinned out to the edge. Hopefully that doesn't infringe on their propietary rout . Russ.

Aha, that explains what I thought I was seeing. Does the routed edge have a sharp 90* shoulder? If so, you might want to keep an eye on the shoulder because this abrupt edge could become a stress riser. Metal machinists often put a slight internal radius on sharp corners to eliminate stress risers in metals that move or may be subject to fatigue factors. BTW, Taylor uses a round endmill to eliminate stress risers.

Rout
 

Did not know about stress risers. Thanks for that. Very useful knowledge. Luckily I used round bottom bit to start, then removed the rest of the wood and then soften d the edge with sand paper. A fellow I used to know who grew up in Appalachia said "even a blind pig finds a mushroom now and again. " seems appropriate to me in this instance. LOL. Russ

Strung up
 

https://i.imgur.com/XaJKiavl.jpghttps://i.imgur.com/yvjxvs2l.jpghttps://i.imgur.com/FNqknQGl.jpghttps://i.imgur.com/3oIOavbl.jpg
Well, I strung it up 2 days ago. Glued with hide glue, no top binding. Initial impressions are: Happy with the overall volume, and sustain. The mid range and treble are what I like, however, the bass response is less than what I usually get from my X brace/ lattice braced guitars.
The top seems stable, so far. I am going to play it for awhile and see how it develops. unless the bass response improves it might get a new top braced X brace/ lattice. That bracing can be seen on the Imbuyia 'torrefied sitka thread from a few weeks ago. Russ Parker

I would have expected that to have less bass response too. Some of those old old Larson guitars used that laminated patch around the sound hole like that. They were also stiffly braced. They were built like tanks and took years to brake in but when they did they were sweet.

I applaud your experimentation, something I gave up doing a long time ago.