Roasted, Caramelized, Vulcanized, Heat Treated, Torrified, Cooked, call it what you want, manufacturers sure do! Heating wood to change its cellular structure and reduce its moisture content is what it is, regardless of your preferred adjective! Ok, now that I have got that off my keyboard, let’s dive in!
Thermally treating wood is known by numerous names but it all goes through a similar process. While each ‘Roastier’ (ooh, so fancy!) may have its own process, the typical roasting process looks like this…
- Dimensional Lumber is kiln dried by slowly heating the wood.
- It is dried out until it reaches 0% moisture content which removes any chemicals.
- The temperature is then raised considerably and the wood cooks for several more hours.
- The wood's natural sugars are rendered inedible by insects and mold.
- The wood is cooled and then 6 to 7 percent moisture is restored.
After the roasting process, the wood looks darker in hue and just like an older, naturally aged piece of wood on a cellular level.
These days, roasted woods are being used as necks, bodies, and tops on acoustic guitars by Electric and Acoustic manufacturers alike. While roasted maple necks have been en vogue for a minute now, heat-treated tops on acoustic guitars are increasing in popularity. With companies like Fender building USA-Made Strats, Teles, and basses out of roasted pine (see the image below!), roasted woods are only going to rise in popularity. I find the most obvious reward in the roasting of neck material. In fact, the roasted spruce tops I have experienced on some acoustic guitars left me wanting more but we will dig a little deeper into this later...
Now that we know what roasted wood is, how does it affect performance, and why am I paying extra for it? As with anything, there are pros, cons, pluses, and minuses to consider here, so let's do all that!
PROS and Pluses:
Roasted woods are more dimensionally stable than non-roasted woods. It does not shrink or swell with the same capacity as it would have before the roasting process. This makes for a great neck material, especially in areas that experience the four seasons in all their instrument-destroying glory. Remember the 1st time you felt the sharp fret ends poking out of the fretboard? Your neck shrank. It lost a little width due to being dried out and, since metal doesn’t shrink and wood typically does… well, you know! Those sharp ends need to be filed off before the neck is comfortable again. A benefit of Roasted Wood is that it's less prone to shrinking and/or that it will shrink less. Keep in mind, if your fingerboard is not roasted, normal shrinkage is impending!
Personal Experience: I have a Roasted Maple Neck with a Brazilian Kingwood (unroasted) fingerboard seasoning in my studio right now and the board has definitely shrunk while the neck has stayed straight.
Now THAT’S some shrinkage!
Actually, this guitar was getting refretted but it can sure feel like they are sticking out that far sometimes!
The Roasting process reduces weight but only slightly as it is directly tied to how much moisture is cooked out of the piece of wood. Makes sense! It also slightly reduces the dimensions of a piece of wood.
It “ages” the wood by collapsing its cellular structure so it looks more like an old piece of wood when examined under a microscope.
CONS and Minuses:
Heat treating wood ultimately weakens its strength and pliability. The moisture in a piece of wood allows for a bit of flexibility which is not an entirely bad thing considering your neck most likely has a truss rod in it. Or considering an acoustic guitar top NEEDs moisture and pliability to perform correctly. The reduction of strength is minimal and very hard to determine until you have cooked a piece so long that it becomes brittle and falls apart. In other words, this isn’t much of a concern since no one would cook a piece to that extent for a musical instrument.
Wood becomes more brittle through the roasting process so it is typically harder to work with. Think about how ebony loves to tear out in chunks compared to regular maple.
The aforementioned reduction in pliability adds some credence to why some roasted spruce tops on acoustic guitars don’t always sound great, at least to my ears. The top of an acoustic guitar NEEDS to flex to push sound efficiently. However, they also need time to break in, perhaps, even more, I suppose. Sigh... If any knows from experience, please drop me a comment!
Roasting adds to the price, considerably. We have 2 expenses here, though: the wood (instrument grade stuff is already kinda pricey) and then the labor involved with the heat-treating process. That’s why it costs twice as much. Add figuring into the mix like Flame or Birdseye along with roasting, and you have one expensive neck blank, my high falutin friend!
Just a Couple of Subjectives:
If you like figuring on a neck to pop, then you’ll likely dig how figured maple, in particular, reacts to the process. Flame and Birdseye maple seems to earn an Extra A on their grades after being heat treated. Finishing it with something glossy makes it burn bright!
Cooking a piece of wood will darken its appearance. The longer a piece of wood spends cooking, the darker it gets. If reaching a specific moisture level is the aim of the Roastier, then any given piece could take longer or shorter than average due to existing levels of moisture.
It smells like Woodshop Class. Remember that smell of burnt wood? Well, roasted woods carry a much lighter version of that scent, at least to my Old Factory. I received an unfinished roasted maple neck and, upon unboxing it, was transported back to birdhouses, cutting-boards, and wood burning kits back in the 8th grade. Minus the paralyzing fear that the band saw would claim one or all of my fingers, of course. Once you apply a finish, you most likely won’t smell it.
Let's not lose our heads here...
Your environment still matters! It’s still wood, not carbon fiber, so don’t have unreal expectations. We are about 20 miles north of Chicago, and we get ANNIHILATED by the weather. I think it was 2019 when we had a low of - 48 in the winter and 116 that same summer. That is an INSANE temperature range, and the fact that we expect guitars made of woods that only grow in tropical environments to handle this weather, let alone the stupid things we do to them is even more insane!
And that’s about all there is to have to sort through! This is a pretty easy thing to grasp compared to some other things discussed here at Matt's Blog. Roasting certainly is cool, but you know, every one of your favorite songs recorded prior to 2015 probably doesn't feature a guitar constructed with roasted woods. So, there's that to consider. As mentioned, I have a neck with roasted maple but it's not a must-have for me, just something cool to have in the collection. Ultimately, if you want a maintenance-free guitar, then check out Carbon Fiber Guitars, as anything made of wood will experience some shrinking, swelling, shifting and will require routine adjustment/maintenance.
Thanks as always for stopping by!
Written by Mathew Jenkins, who gets torrefied regularly.
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