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View Full Version : Some Thoughts on Working with Torrefied Spruce



sequoia
05-21-2016, 07:23 PM
Some thoughts on working with the torrefied spruce top (terriefied spruce?) from SMD. Some good and some not so good: First the good news.

- The stuff looks great! A "real" classic amber look right out of the box with no use of dyes. Pretty honey/gold.

- Extremely percussive with a nice bell-like tone.

- Thickness sands quickly and politely with good consistency.

- Nice book matching and grade. I'm no wood grader, but I would guess it is solid 2AA or better. Unfortunately, I got a little flaw that was hidden and only appeared after thinning. Who knew? Not a biggy.

Now the bad news:

- Very brittle and difficult to work. The tear-out possibility is very real and when it tears it fractures out the piece. So far any tear out has been on the down side and minor, but it happens fast and goes deep with the chip completely separating and disappearing. Really nasty.

- Smell: Smells like cooked spruce. Not bad but not very nice either.

- Curling: This stuff will curl like a potato chip in a heartbeat at the merest whiff of moisture. Not really a big deal, but it spent weeks stickered in the iron maiden until tamed.


Conclusion: VERY difficult wood to work with. Brittle with little elasticity. But the biggest issue is fracturing chip-out which is no joke. Repair possible, but challenging. Trying not to go there. I'm not out of the woods yet and have to trim the waste after I glue up the top and I'm approaching this task like I would if I had to deal with nuclear waste or a rabid cat: Very slowly and very carefully. No router and only the sharpest of thumb planes. I slather shellac on the thing before I even attempt working with it. Plus, I'm not a religious man, but I've been thinking about prayer.

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Sven
05-22-2016, 12:15 AM
Sounds as if it's turned into a piece of cedar, similar to the cedar I last worked with! Good luck man. Pucker that arse, as Ken does.

Timbuck
05-22-2016, 02:08 AM
Sounds as if it's turned into a piece of cedar, similar to the cedar I last worked with! Good luck man. Pucker that arse, as Ken does.
You leave my arse out of this :o known as the "lesser brown starfish" where I come from.;)

printer2
05-22-2016, 03:35 AM
That rosette looks fabulous with the color of the top.

cml
05-22-2016, 05:55 AM
I agree, the rosette looks great.
How's your first soprano coming along =)?

sequoia
05-22-2016, 06:33 PM
That rosette looks fabulous with the color of the top.

Thank you... Because I'm not sure I like the wide look with the thick purfling border. I usually do thin and with delicate purfling so this is something new and different. We shall see once it is finished out, but I think it might be just too big for an uke... It's all about proportion.

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Note there are no tear-outs on the rosette cut because I slathered on three (3!) coats of shellac, but check out the inside where there was no shellac and what happened when I cut the sound hole. No splinters, just complete fractured tear out. I count 6 tear outs. Shellac is a must on torrified wood. Shellac is my friend.

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Beau Hannam Ukuleles
05-22-2016, 07:30 PM
...Brittle with little elasticity.


Thats what makes BRW such a great tonewood.

erich@muttcrew.net
06-03-2016, 10:55 AM
I can verify your concerns with torrified spruce:
extremely brittle
subject to tearout fracture - major multiple fracture in my case
subject to bending/curling


On the other hand, it is strong, has a really nice color and, with the exception of routing tearout, is not hard to work with.

In my case, the smell isn't noticeable.... any more - it was when it came out of the oven :D Yes, I do my own "torrified" (in other words "baked") woods - have had very good success with some woods, not so good with others.

The fracture was bad. I was flush trimming the top, using the back as the template, and had my dremel/rebate setup at top speed (35,000 rpm). When I got to the tail end of the treble side, a huge piece of wood split off right along one grain line and a narrow strip split along the next grain line. Since the edges were clean cut, I carefully glued them back together, and here's what I ended up with (after attaching the braces):

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kerneltime
06-19-2018, 02:04 PM
Thats what makes BRW such a great tonewood.

What is BRW?

printer2
06-19-2018, 04:45 PM
Sounds as if it's turned into a piece of cedar, similar to the cedar I last worked with! Good luck man. Pucker that arse, as Ken does.

I feel the same about how baked spruce is like working with cedar. So did that stop me? I just had to do it, baked cedar.

https://i.imgur.com/CJonbIB.jpg

With baked birch pallet wood also. I hope the bridge stays glued on.

jcalkin
06-20-2018, 07:48 AM
After making dozens of guitar bodies with torrified red spruce I came to the conclusion that red spruce would be just as good, the working characteristics were the same. However, the tonal differences were extreme, with the red spruce totally living up to its hype. Though flush trimming caused some tear out, routing for purfling normally cleaned it up nicely. Changing suppliers made a world of difference. The color was the same but the tops were not floppy and tear out was minimal. The good tonal qualities remained. I assume that the difference was in the baking techniques. Torrified Sitka from the second supplier was also wonderful stuff. Torrified curly maple was always wonderful, beautiful wood to work with. I don't know who the suppliers were since the bosses and office staff at Huss & Dalton took care of all the details and I never asked.

Beau Hannam Ukuleles
06-20-2018, 08:12 AM
What is BRW?

Brazilian Rosewood