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Does anyone have experience of an opinion on stabilizing wood for guitar backs and sides? I am talking about wood like spalted maple or sycamore, big leaf maple and other woods that are soft and associated with dampening the vibration of the sound box. This process, mostly done by vacuum, literally sucks the air out of the wood pores and fills it with acrylic, epoxy, etc (many different products). This stabilizes the wood, makes it harder and increases the density and durability. I think it would also help solve the dampening problem of some of the softer woods. I haven't heard of it being done on the scale that would need to be done for backs and sides but it seems entirely possible. Mostly pen blanks, pistol grips, knife grips, etc are treated this way. My curiosity has been peaked because I have some very nice spalted sycamore and killer red streaked box elder that would make striking instruments but are not the ideal woods for producing quality instruments.

Any information or opinions would be great!

Thanks, Ken

I've done a lot of research on stabilizing wood recently. No reason you couldn't do it on a larger scale such as a back and side set. It would take a lot of wood hardener that's for sure. As long as you have an air tight container big enough you can do it. I just did some dying of some pear burl for a rosette I'm working on. I'm also going to start stabilizing my bone nuts and saddles in minwax wood hardener.

Again, as long you have a container large enough to hold the wood and the wood hardener you can do it. If you have vacuum set up, get a vacuum bag and place a large rubbermaid container like they use for hold wrapping paper, put a bunch of holes in the lid and along the sides, right near the top (this will alow the air to escape the container but won't allow the bag to be sucked down into the cavity of the container), fill it with the wood hardener and the sides and bring it under vacuum, if the lid collapses, maybe screw a "brace" on the top or inside to stiffen it up. My guess is you'll need at least 2-3 hours with thin wood to get it all the way through. Pen blanks and knife scales they say require a minimum of 5-6 hours and more is better.

Now, what's going to happen with the wood after you've stabilized it Well of course it won't ever breath again like wood as you've completely filled any voids. You won't ever have to worry about it warping, shrinking or swelling from RH changes....but who knows what it will sound like. It might just thud like really hard cardboard with all the cured wood hardener in there....?

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I was wondering this exact same thing as well, Ken. Thanks for the info, Rod!

Sound was my main concern. I'm not sure how a back flooded with hardener would work out sound-wise, but I guess one could get around that by using a double back? I've seen so many beautiful pieces of spalted wood that would make amazing back/side sets if it weren't for the softness/stability issues, so I think it's definitely worth a shot.

Ever play one of those cheap Formica Martins? Bet it's gonna sound a lot like that.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Or, you could build it into an electric.
Maybe a nice looking top cap?

Or, you could build it into an electric

A lot of the serious pen turners do it under pressure instead of under vacuum. Apparently, they have better luck compressing the air bubbles than sucking them all out.

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Mike Lindstrom

I was under the impression the process was first vacuum to extract air and then pressure to fill the cells all in the same sealed tank of acrylic? Now there is another thing, penertration will have much to do with viscosity me thinks.

Cheers

Kim

Thanks for your input. I believe that I will try the vacuum technique. The stuff I am using as a stabilizer is water thin (maybe thinner). After the air has been sucked out, it should penetrate well.

Ken

I bought a tight curl spalted piece of maple to resaw for a few backs. It cost $20 plus shipping. I sent it to a company to stabilize with vacuum plastic. That cost $100 plus shipping. I have not resawn it yet. The stabilizing process seems to have reduced the ability of the light to show the curl, and overall dulled the wood. Also, for those who like to accent the curl with a light stain, that will not be possible if stabilized. Anyway, there are companies that specialize in stabilizing small batches of wood, if you really want to go through with it, but I don't think it was worth it and I don't like the result.

Last year I built a spalted mango small jumbo. The wood, especially for the back, was quite punky. I was a bit nervous to work with it. I didn't go through the vacuum process many of you discussed above. Rather, before joining the back panels, I treated them with Minwax's stabilizer, giving the wood as much as it would absorb, which was almost the entire can. I left the panels to sit over night and came back the next day to find them curled like potato chips! Fortunately I had done this prior to joining the plates and thicknessing because the wood really shrunk in some areas. I got the plates flat enough to join, thicknessed the back but left thicker than I would normally leave a back, then wicked in an ounce and a half of thin CA. At this point, I finally felt I could work with the back. I bent the sides, and afterwards wicked CA into the pores. Because of all the stabilizer and CA in the wood, I used epoxy on any wood that was bonded to the back or sides.

The guitar turned out very nice. The figure draws a lot of attention. I was concerned about what the sound would be like. I combined the mango with a lutz top. The guitar has a richness and presence that surprised me given how punky that wood was to begin with. I have had a few offers for the guitar, but given what a hassle the wood was to work with, I doubt I will do another one soon. So I want to hang onto this one for awhile.

Ken

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Ken, I went to your website and took a look at the Splalted Mango guitar you constructed. WOW!!! A very nice looking instrument. Gives me incentive to pursue the stabilizing of my spalted Quartersawn sycamore. I will keep you posted.

Ken H

Thanks Ken! Good luck with your spalted sycamore!

Ken

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Hi Ken,
That guitar is one of the most exceptional guitars I have ever seen. I have no doubt it draws a lot of attention. I look forward to the day I am at your skill level.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

Thanks I am sure you will be there soon, Joe! And welcome to the OLF!

Ken

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