Veneering compound curves

[Michael Rowan]

Hello Everyone,

I am new to this forum and was directed here by Joe at Veneer Supplies. My question is in regard to veneering over compound curved shapes, mainly guitar bodies. I am a boutique guitar builder and I am concerned with the longjevity of the flamed and quilted maple supplies as used in my industry. I would like to see if veneering would be a viable alternative for my products, one of which has quite sharp break-over angles on the top. The model in question is the Sweet Six listed on my site at rowanguitars.com. I would appreciate any advice/guidence anyone could provide.

Thanks in advance,

Michael Rowan
Owner
Rowan Custom Guitars
Garland, TX

[Frank Drew]

Michael,

If I understand your question correctly, as far as I know no one has come up with a method to make veneer curve in more than one direction just with pressure; it will take a pretty tight curve in that one direction, but after that (compound curving) you have to start making cuts.

In other words, you can probably veneer a globe (or a basketball), but there'll be a lot of cutting and fitting involved.

[Rick Akl]

On the Wood Whisperer website there is an interview/ shop tour that I saw with David Marks of the "Wood Works" TV series. In the video (http://www.youtube.com/watch?v=A0D6Jey28dI) he talks about one of his current projects and explains how he accomplishes the compound curve lamination which I believe has a solid core. I do not know if that will help you with a curved bodied guitar build but it is probably worth a look. Alternatively you could laminate a thinner 2/4 or 3/4 stock contoured top surface with a solid back body but I know nothing of guitar acoustics and do not know how it would affect the tone. Best of luck and let us know how it goes!

[Pat Mullery]

Actually, I have veneered the inside of a 6' diameter hemisphere. It is one of 2 (the second one will be veneered shortly). It is a seating niche in a waiting room of a children's hospital. The same method could be used to laminate other objects. One key is mapping the curved surface as a flattened pattern.

[Richard Coers]

Hasn't curly maple been used on violins for a couple hundred years? Long enough for some folks to call that figure, fiiddle back maple anyway. Probably a hundred years with guitars.

[Mike Henderson]

Hasn't curly maple been used on violins for a couple hundred years? Long enough for some folks to call that figure, fiiddle back maple anyway. Probably a hundred years with guitars.

That wood on the back of a violin or viola or cello is solid wood - it is not veneered or bent.

Mike

[stephen thomas]

tried your link with this result:


This domain is pending renewal or has expired. Please contact the domain provider with questions



Regarding the question:
1.) traditionally, burl veneer has been used for compound curves; e.g. bombe furniture. Burl is relatively easy to push around in moderately 3D directions, see also Pat M's note about mapping the surface for the cut/mating edges.
I'm gonna guess burl is not ideal for tone?
2.) (can't see your work so more guessing) if you do the mapping, even curly maple might be applicable on something as gradual as say, a cello back, with a center match join = traditional book match anyway.
3.) in recent years there has been a lot of research and practice involving ammonia to flex wood in any & multiple directions as though it were wet noodles or dough. The ammonia is the strength that can kill you or give permanent respiratory issues, so not trivial to play with, but perhaps an avenue to research
4.) I typically use epoxy for curved veneering because it adds no moisture to complicate the lay-up nor warp the assembly. However, i have dabbled with hammer veneering and if you get good with it, it is possible to push veneer to do some interesting things including moderate 3D (see again bombe furniture). However, veneer pushed too far (whatever "too = for a given application) will shrink and may crack on drying, requiring fillers which are unobtrusive visually but might impact tone.

I am well aware that hard/sugar maple is under stress. The town took out 4 of our larger trees this year as the deadfalls and casting branches were becoming a road hazard. Even off the road/ into the forest, and traveling around NYS, hard maples are being attacked due to climate change allowing pests to survive winter and thrive further north. However, beyond disease, hard maple grows like a weed. Curly and birdseye maple are common, and it is not a wood that laminating instrument backs and bouts would save much of? For an exploration of tone qualities, i applaud the experiment, though. :)

PS: did any of the manufacturers of cheaper laminated top/back wood ever do arch-tops? It would seem ideal for industrial production. I'm pretty sure there were cheap laminated violins at some point.

Keep us posted!
smt

[Maurice Mcmurry]

Wood does not like to bend in compound curves. Take a look at the process of "spiling" boat planks. What looks like a nice fair curve on a boat plank is shaped like a dogs leg when you lay it flat. There is a rich tradition of using solid wood for instruments. Yamaha has created well respected laminated tone woods. Any compound curve on a laminated instrument is very subtle. The renowned UK builder NK Forester is having good success using laminations on a few of his builds. The domed back of a banjo resonator is often just flat laminations smashed into a dome. I build my dome shapes with solid wood and spiling techniques.

[Edward Weber]

Hello Everyone,

I am new to this forum and was directed here by Joe at Veneer Supplies. My question is in regard to veneering over compound curved shapes, mainly guitar bodies. I am a boutique guitar builder and I am concerned with the longjevity of the flamed and quilted maple supplies as used in my industry. I would like to see if veneering would be a viable alternative for my products, one of which has quite sharp break-over angles on the top. The model in question is the Sweet Six listed on my site at rowanguitars.com. I would appreciate any advice/guidence anyone could provide.

Thanks in advance,

Michael Rowan
Owner
Rowan Custom Guitars
Garland, TX

I would suggest that Scott Grove is the one to talk to.
https://scottgrove.com/

[Richard Coers]

That wood on the back of a violin or viola or cello is solid wood - it is not veneered or bent.

Mike
My point exactly. I took this statement as he didn't trust solid wood.I am concerned with the longjevity of the flamed and quilted maple supplies as used in my industry.
I thought he meant that is why he is looking at veneer. don't know of any contoured wooden instruments that use figured veneer. But I have no proof of that.

[Jim Morgan]

I would suggest that Scott Grove is the one to talk to.
https://scottgrove.com/

I second the Scott Grove recommendation. Took a class from him on compound veneering. He first softens the veneer using a mixture of water, glycerin, white glue, alcohol, and acetone (would have to look up the proportions). When the veneer is dry but still flexible, it is coated on one side with Titebond 1; the substrate also gets a coat of Titebond 1. When these are dry, the veneer can be tacked to the substrate with a small hot iron. The trick is to tack down the veneer is spots so that pleats are formed. Wood fibers in the veneer will slide past one another while it is softened so the pleats can be ironed down.

This works surprisingly well over some fairly sharp curves, but I don't believe you would have much success bending a piece of veneer over a sharp edge.

[stephen thomas]

model in question is the Sweet Six

Found one on the net.
So they are electric solid bodies?

For some reason i thought you were doing archtops like Ken Parker.

Ken is somewhat accessible if you are serious.
And he likes weird ways of using wood and other materials. :)

https://kenparkerarchtops.com/#renewing-the-form

https://kenparkerarchtops.com/archtoppery#archtoppery-contents

Also, there are many people on acousticguitarforum.com who are doing similar thin material joins on the cut outs and relief areas of acoustic guitars. Not veneer work per se, but similar scale.
For your solid body, you could just veneer all the breaks. Perhaps with a contrasting wood like ebony or snakewood (as the acoustic guys do sometimes). Then level it, and overlay the face/top veneer.
Even if they won't appreciate your electric perspective, there is a lot of talent on that site and you can get your maker questions answered.

Overall FWIW, you may or may not find it satisfying to attain this with factory 1/32 or 1/40" veneers.
Plan on making your own, thicker veneers, or buying some specials.
I helped a friend move shop including his veneer inventory last fall that nearly filled 1/2 of a 2 car garage, even after all that was thrown out. Mostly 1/28" (the old standard) and thicker, up to 1/8".
AFAIK it is still FS, but not in small lots. I got a nice flitch of persimmon that is slightly thicker than 1/28".

smt

[Maurice Mcmurry]

Here is a video of the Sweet Six.

https://youtu.be/DO-Wm3xdhtY?si=lTRns-O7dFZpHkTf

[John Kananis]

This is a good discussion regardless but the OP posted once on this site, 14 years ago.

[Maurice Mcmurry]

It is an awesome guitar and Fazio's Frets and Friends is my favorite instrument store. Covering one of those with veneer is beyond the scope of my experience.
Maybe ammonia gasification of the veneer followed by vacuum bagging?

from the web,
The 3D-moldability of veneers, as opposed to the moldability of plastic or other materials, is limited because of the characteristics of wood. Veneers can be modified by physical, chemical, or mechanical treatment. We chose water and ammonia-water solutions. After treatment for an established time, the moldability of veneers was examined. The level of concave deflection of a test piece of punch-molded veneer was assessed. Three sets of test pieces were tested by dipping in cold water (20 °C), hot water (95 °C), or a 25% solution of ammonia, for different durations of time. The results showed that the 3D-moldability of veneers increased by 66 to 119% after plasticization by a 25% solution of ammonia, unlike the unmodified veneers with a moisture content of 7.65%. The increase in moldability was significantly higher in comparison to the veneers modified by dipping in cold water (20 °C) and hot water (95 °C). Futhermore, the relationship between the moisture content of the veneers after their modification/plasticization, the level of concave deflection, and the molding force in relation to the level of concave deflection were examined.
https://www.researchgate.net/publication/269401678_3D-Moldability_of_Veneers_Plasticized_with_Water_and_ Ammonia

[Jim Becker]

That wood on the back of a violin or viola or cello is solid wood - it is not veneered or bent.

Mike
Correct. The fronts and backs are literally carved to the contour while keeping precise thickness, some of which is done with cute little hand-planes with curved bottoms. :)

[Zachary Hoyt]

Correct. The fronts and backs are literally carved to the contour while keeping precise thickness, some of which is done with cute little hand-planes with curved bottoms. :)
Or in my case with an ugly big Kutzall carver in an angle grinder. I'm too cheap to buy those planes...

[Maurice Mcmurry]

This is a good discussion regardless but the OP posted once on this site, 14 years ago.

Thanks John, It is always good to be reminded to start at the beginning and look before you leap.

[Mike Henderson]

My point exactly. I took this statement as he didn't trust solid wood.I am concerned with the longjevity of the flamed and quilted maple supplies as used in my industry.
I thought he meant that is why he is looking at veneer. don't know of any contoured wooden instruments that use figured veneer. But I have no proof of that.

The back of many cellos are figured maple, either a solid piece or two pieces resawn and then glued together. You'll see a vertical glue line. Many of those cellos were made in the 1700's and are still being played - with the same back.

I suspect the same is true for violins and violas but I'm not as familiar with them as I am with a cello.

Mike

[Jim Becker]

Or in my case with an ugly big Kutzall carver in an angle grinder. I'm too cheap to buy those planes...
Keep your eye open for them "out there" used...or make some of your own. Pask Makes has done a few small planes like this on his channel on the 'Tube. He used metal, but you can do wood, too. I had one but sold it here in the classifieds last year 'cause it never got used. But it was cute!

[Maurice Mcmurry]

Or in my case with an ugly big Kutzall carver in an angle grinder. I'm too cheap to buy those planes...

The few guys I have met that make carved instruments also carve their own planes. Making a violin plane is on my ever growing to do list. I have one in mind to copy. It was made by R.L. Givens and hangs on a nail of honor at the mandolin factory. It looks a little like this one.
521144
snip from eBay
more from the web including a plan
https://finelystrung.com/2008/08/16/violin-making-planes/

[Zachary Hoyt]

Thanks for the link. Making finger planes looks like fun. I have gotten pretty used to the way I carve now, but it would be interesting to try another way. I've carved the plates for 34 fiddles, 7 archtop mandolins, 5 archtop guitars, a cello and a bass so far using abrasive carving, and it's fast but also loud and messy.