Just an uninformed question from a non-builder. Is it the curl that's the problem or is this a general property of all redwood, including redwood with straight grain? Sorry if the question sounds stupid.
Curly Redwood
- Thread starter Moore Bettah Ukuleles
- Start date
Kent Chasson
Well-known member
The curl is severe runout (grain that is not parallel to the surface) that changes direction with every curl. It reduces the stiffness along the grain and can create serious structural weakness at a place of high stress concentration (like where the bridge is glued).
BlackBearUkes
Well-known member
In my experience with all redwood, it tends to be more brittie and prone to splits and cracks easier. It also tends to be very stiff and light in weight which makes for a nice top wood.
Duane, how is the lamination done? What glue is best used?
I also have some of this very suspicious curly redwood. When I sanded a piece to proper thickness, it broke like potato chips, so I set it aside. This thread has revived my interest and has put me to thinking about vacuum-bagging a laminated top in the 25' radius dish.
Beau Hannam Ukuleles
Well-known member
This concert top is 0.040" (bridge patch is 0.020" rosewood veneer) but the bracing was designed with that in mind.
I'll epoxy the bridge on, tradition be damned!
I'll epoxy the bridge on, tradition be damned!
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Moore Bettah Ukuleles
Well-known member
It's not the bridge you should be worried about separating from the top. It's the bridge taking a chunk of top with it if it does fail. In that case I'd rather use a glue that I knew would fail before it did such damage. .040"? Really?
Beau Hannam Ukuleles
Well-known member
True Chuck, but my reasoning is thatWest system Epoxy would seep into the underlaying bridge plate at that thickness giving more strength to the curl.
Some modern classical guitars have a 0.040" top and they have a lower bout twice as wide so i reckon im ok (with the bracing it has, which aint 3 fans), but it all may explode in my face when it is strung up. Its all a bit of an experiment but ill let you'all know in time.
Some modern classical guitars have a 0.040" top and they have a lower bout twice as wide so i reckon im ok (with the bracing it has, which aint 3 fans), but it all may explode in my face when it is strung up. Its all a bit of an experiment but ill let you'all know in time.
thistle3585
Well-known member
Here is a photo of a curly redwood tenor uke I made several years ago for my wife. I haven't had a single problem with it. Its all the same top, back and sides. I can't recall what glue I used on the bridge but it hasn't come off. I'm guessing its West System epoxy. The uke has absolutely no volume and dents very easily. My wife likes it because it isn't loud. I wouldn't build another. I built a bunch of semi hollow body electrics with curly redwood. I do know Bill Bussmann of Old Wave uses it quite extensively. You should email him. Really nice guy.
If you decide not to use it then I'll be more than happy to take it off your hands for drop tops on electrics.
If you decide not to use it then I'll be more than happy to take it off your hands for drop tops on electrics.
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Moore Bettah Ukuleles
Well-known member
I was concerned more about the tone. No matter how well braced, any time I've tried very thin tops the tone becomes very bright and one dimensional. Like a banjo.
BR Ukuleles
Well-known member
That's been my experience as well Chuck.
They can be very in your face like a banjo, and some people have asked me for that type of instrument so that they can play lead in a group. So that is a very useful bit of design info for builders to put in the back of the head in case your ever asked for an instrument like that.
They can be very in your face like a banjo, and some people have asked me for that type of instrument so that they can play lead in a group. So that is a very useful bit of design info for builders to put in the back of the head in case your ever asked for an instrument like that.
Beau Hannam Ukuleles
Well-known member
I love a banjo/bluegrass sound (as do a few other people) so im not worried about that 
I ment to say that ill be treating the top with Smiths penetrating epoxy prior to finishing, then epoxying on the bridge with West.
This is an experimental, 'fun' personal build (non customer), something I like to incorporate into my year to keep it all interesting and me on my toes- At the moment it has no binding and has a nice tap and booooiiing to the top
The other piece of this wood i kept at 0.080" for a later concert top.
That idea of laminating some spruce, cedar, straight redwood or even some Brazilian RW to the underside of curly redwood is an interesting idea- perhaps for my next experimental build
I ment to say that ill be treating the top with Smiths penetrating epoxy prior to finishing, then epoxying on the bridge with West.
This is an experimental, 'fun' personal build (non customer), something I like to incorporate into my year to keep it all interesting and me on my toes
- At the moment it has no binding and has a nice tap and booooiiing to the top The other piece of this wood i kept at 0.080" for a later concert top.
That idea of laminating some spruce, cedar, straight redwood or even some Brazilian RW to the underside of curly redwood is an interesting idea- perhaps for my next experimental build
Thanks for the discussion everyone! As a non-builder, though, I'm still left wondering whether this discussion has general implications for the use of any sort of redwood, especially non-curly redwood, as a soundboard. I know I'm not the direct audience for Luthier's Lounge conversations, but I am a consumer and find myself making decisions now and then about what sort of wood to use as a soundboard wood. Thanks ina advance for any additional clarification about the properties of non-curly redwood as a soundboard wood.
BlackBearUkes
Well-known member
Best? Depends on your methods, beliefs and experience. If I were gluing curly redwood and spruce together to make a top plate, I'd probaby use titebond, maybe even a waterproof Titebond. You can use whatever your comfortable with.
As for gluing them together, I'd coat both pieces of wood, bring them together and weigh them down for a good 24 hous, making sure there are absoluety no voids.
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Kent Chasson
Well-known member
Good quality redwood makes a great top. I've built maybe 6-8 guitars with it. I have yet to use it on a uke but wouldn't hesitate. On a guitar, it is similar to cedar in that it is warm with lots of overtones and very fast to respond. It's more crisp sounding than cedar but still has what I call "rounded edges". Well quartered wood is essential in my book because redwood loosed lateral stiffness dramatically once you get a few degrees off quarter.
Yes, having a vacuum pump is very, very nice. I've been using mine to run a fixture for holding bodies while sanding and routing binding channels but it's not a big step to use it for a bagging set-up.
Thanks for the tip on Unibond 800. It seems to be expensive, though, so for purposes of experimentation, perhaps HHG really is the best bet.
I do like the idea of molding the radius into a top.
I've been using mine to run a fixture for holding bodies while sanding and routing binding channels but it's not a big step to use it for a bagging set-up.Thanks for the tip on Unibond 800. It seems to be expensive, though, so for purposes of experimentation, perhaps HHG really is the best bet.
I do like the idea of molding the radius into a top.
With some thought, and a membrane, a vacuum frame system could easily be built. HHG for lamination still scares me just a little, I am still a beginner with it. I know there are members here who use it for laminating. With warm pieces, and a well though out plan, I think it would be great. Especially with a vacuum frame for speed.
As a newbie, I am sticking with solid tops until I begin to understand what is going on a little bit more.
Unibond 800 cures brittle hard, as does HHG. Titebond does not. Titebond will give a damping effect in a lamination, I do have experience with this. The Red Cap Titebond is better in this respect than Titebond III. I would not laminate a top with Titebond III no matter what. No way, no how.
Molded radius is a cool idea. When I spent a week with Pete, we built Reso ukes. The tops, and backs were Baltic Birch ply, with nice veneer. Flat, however. If we laminated, we could have chosen the species for the layers, chosen the adhesive, and created the radius. Win, win, win. One of these days I am going to make new body for the Reso I built that week, with a radiused back.
As a newbie, I am sticking with solid tops until I begin to understand what is going on a little bit more.
Unibond 800 cures brittle hard, as does HHG. Titebond does not. Titebond will give a damping effect in a lamination, I do have experience with this. The Red Cap Titebond is better in this respect than Titebond III. I would not laminate a top with Titebond III no matter what. No way, no how.
Molded radius is a cool idea. When I spent a week with Pete, we built Reso ukes. The tops, and backs were Baltic Birch ply, with nice veneer. Flat, however. If we laminated, we could have chosen the species for the layers, chosen the adhesive, and created the radius. Win, win, win. One of these days I am going to make new body for the Reso I built that week, with a radiused back.
BR Ukuleles
Well-known member
Here's a link to building a "Double Top" as they are referred to in guitars.
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