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Hello again to the forum. I have been working on a new project that I decided to post a bit here due to the excellent response and reception I've received from this group. This project is one of my Z series designs but I'm using a new material for the neck. I have read a bit about using "Roasted Maple or Caramelized" as some put it, for the neck. As usual, I've included a blog post for a bit more detail. http://wp.me/p2IaxD-gq.

Thanks as usual for allowing this outlet for me-

This technique has been around since the days of the Archer's and spear chuckers. Bow makers used a technique called fire hardening on their bows and arrow tips. The scientific name is Torrefaction. One manufacture that I can think of that uses roasted maple necks is Ernie Ball Music Man. I believe a few smaller builders like Anderson and Suhr use them too. I'm sure others do but just don't advertise it. Many guitar factories and builders tend to be secretive about their processes. Now Gibson uses something called baked maple for fingerboards. It's basically the same process....mike

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Guitars, guitars and more guitars.

Recently I tried a bit of heat treatment to Oak. My objective was to impart a darker colour (for fretboards) that went deeper into the wood than any dye can. Not exactly scientifically controlled. I did it in a domestic oven and tried to keep the humidity up. Colour wise it certainly worked and the piece of Oak hasn't cracked or exploded yet.

I'm a believer in cooking wood, mainly soft wood for guitar tops. I believe what it does is speeds up the natural aging process of wood. Anyone that has hamered old soft wood (50 years or more) knows how much harder it has become.

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Joe Beaver
Maker of Sawdust

The bottom board is roasted maple that I plan to use on my challenge build neck if I don't bind the fb. You can also get roasted oak as well

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Michael, at what temp and for how long did you "cook" that piece of oak? Looks nice.

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Formerly known as Adaboy.......

Does anyone have a good supplier for torrefied maple? The process requires a nearly pure nitrogen atmosphere as the kiln is maintained over 400°F and would otherwise cause the wood to combust, so it should always have a dark brown color. I would love to build some necks with it.

If anyone is curious, I have an extensive and controlled data set on the dimensional stability of untreated and thermally modified poplar, maple, and ash. Even after soaking in water for several months the torrefied lumber experiences single digit percentage changes in some species. In all cases it is far more stable than untreated wood and was incredibly resonant.

This is where I got mine. http://www.exotic-woods.com/index.html The last time I was there, I saw that they had curly roasted maple as well.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

From what I have read if you take the process to far you can go from hardened wood to wood that is soft and brittle that you can break it with your bare hands easy like a wafer. I have also seen something where after the hardening process they force humidify the piece. Hugh do you know anything about that? Do you need to introduce water back into the wood after this process? Or will it acclimate naturally? Hugh is your data on this available as a downloadable file...Mike

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Guitars, guitars and more guitars.

Thanks Alex! Their name sounds awfully familiar, and I remember the samples I had came from a supplier in Ontario. I will be very curious to see if its the same place when I check my notes.

Mike-- the process absolutely changes the strength characteristics of the wood. The standard procedure takes the wood to 0% moisture content. Also, the temperature is sufficiently high that the lignin cross-links extensively (a major reason why it becomes do stable) while virtually all of the light organic molecules are released. The loss of light organics and sugars is theorized to be very similar to natural changes as wood ages. Among other things, the strength to weight ratio increases and makes the wood more resonant.

After thermal treatment there is no reason to subject the wood to any specific moisture conditions. At equilibrium, it tends to be capable of carrying very little moisture... 2% to 3% is not uncommon at room temperature and 50% relative humidity. In some species strength is adversely affected more than others. In general the wood becomes more rigid (evidenced by a slight increase in modulus) while its ultimate strength decreases. Failures due to stresses applied perpendicular to the grain are often very odd looking, most similar to rotten wood, with the crack following a jagged line parallel to the load point. From memory, maple holds up much better than poplar. If the process is not followed correctly and small amounts of oxygen are allowed into the chamber or the temperature goes too high there is indeed a risk of destroying the wood. This is due to the fact that torrefication reaches the limit of what wood can withstand. The required temperature necessitate a pure nitrogen atmosphere as it will otherwise combust spontaneously. It's also why the stuff smells so much like smoke.

I will need to compile some of the data, since I was canned while the long term soak test was still ongoing. Once it is all together, I will make it available for download.

Thanks Hugh. The reason I asked about reintroducing moisture to the wood was related to an article I read explaining what Gibson baked maple was. The article mentioned this. i couldn't find anything else on this but the Gibson article. I can not recall where I read this story on Gibson baked maple. Maybe Premier guitar magazine. Thanks....Mike

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Guitars, guitars and more guitars.

Not sure! It was fairly gentle compared to thermowood treatment. I'll take a guess at around 175 C. I do know that I cooked it for just over an hour with a large container of water in the oven. Don't know how effective the water was, probably not much but better than nothing. The whole thing was a quick experiment and of course I will have to do many more and monitor them over many months if not for a year or so. I'm looking to use something fairly hard, durable and local for fretboard use. I've used Bog oak and new Oak with it's natural colour without problems on Nylon string instruments.

Just a quick update on the neck project -

Thanks for all the activity on this topic. I found it to be very interesting and I like the results so far.
Pretty cool trivia to be had. Thanks for all the expert and welcomed responses-

I've completed the neck for the most part and will finish up the fret ends tonight.
I find the material to be fun to work with.
I love the smell of a campfire and that's what it reminded me of during the process.
I also love the color once a finish is applied. Looks very warm and comfortable.



Thanks to all-