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etkre
10-08-2009, 03:00 PM
I just got a hold of a large section of freshly cut black walnut (felled today), about 2-3 feet in diameter. How do I go about drying the stuff for use in uke making? It's really beautiful, so I want to go about it the right way. Should I quarter saw it down into thin sections now? Are there any methods to speed up the drying process?

Thanks,
Eric

Pete Howlett
10-08-2009, 03:09 PM
Quarter it into billets by splitting it with a wedge and air dry it - wait a long time.... see those Taylor movies linked in another thread to see what I mean you lucky fellow :)

etkre
10-08-2009, 03:32 PM
Thanks Pete. Do you ever work with wood that wasn't dried by a supplier (I assume you're not felling koa across the pond)? I'd love to see a video of you starting from the log.

Pete Howlett
10-08-2009, 03:35 PM
I had my cutter in California resaw some wet koa - I regret it now as most of that wood did not dry well...

RonS
10-08-2009, 03:47 PM
There are books written on this

Short Version
Cut it
Sticker it
Seal the endgrain.
Wait a year or two

Long Version
http://owic.oregonstate.edu/pubs/for55.pdf

etkre
10-08-2009, 05:12 PM
Whoa, that's a lot of info! Thanks! I also have a 2' diameter section of what I think is pine that has been outside for 2 or so years without any signs of cracking. Do you think it might be stable enough to build with, if not for a traditional acoustic, perhaps as a hollow-body electric like Pete's Uklectics?

schubs
10-08-2009, 05:23 PM
When making a ukulele, i think you are suppose to not use light weight woods like pine, but i could be wrong.

donnercruz
10-09-2009, 02:48 AM
There is a local guy here in Santa Cruz who has built his own vacuum dryer and dries his own wood. I saw the set up, and it is pretty cool. The biggest limiting factor is the size of the materials used to build the dryer.

He has a website and sells a book on how to build your own.

Vacuum Kiln Drying (http://vacuumkilndrying.com/index.html)

RonS
10-09-2009, 02:48 AM
Whoa, that's a lot of info! Thanks! I also have a 2' diameter section of what I think is pine that has been outside for 2 or so years without any signs of cracking. Do you think it might be stable enough to build with, if not for a traditional acoustic, perhaps as a hollow-body electric like Pete's Uklectics?


Without seeing it and checking it out, it is hard to tell.

Typically, if the wood is still in log form, the center is still not dry enough. Plus, if it's been outside on the ground, insects my have gotten into the wood.

The old wife's tail is wood dries 1" per year.
It's been my experience that this is not always true, just simply a guideline.

Pete Howlett
10-09-2009, 04:02 AM
And a very good guideline - koa can dry faster...

etkre
10-10-2009, 02:31 AM
The walnut is split and the long wait begins. Most of it has nice tight and straight grain, with color varying from dark chocolate to milk chocolate. One wedge is unsuitable for an acoustic because it has a weird bending of the grain by the heart wood. I split it further and discovered a sawed branch base that was "swallowed" by the tree some 30 year back! I think I might be able to squeeze a solid body out of this section, but who knows...

koalohapaul
10-10-2009, 02:42 AM
Just remember to sticker well. Airflow is key in drying green lumber. Almost all of our lumber comes green, straight from the mill. 4/4 dries a lot faster than 8/4, so I prefer it for that reason. 8/4 yields more sets per block, but we don't always have the convenience of being able to dry and season the thicker stock.

I usually have one load on the wall, which I sort, grade, and mill into billets. There's another load in the kiln, and one stickered in the back of the shop. I keep a big shop fan blowing on it 24/7. The 4/4 drops to about 20% in about a month, even if they're dead green. If I'm lucky and they're all relatively dry, I rotate them in the kiln, and they're done in 4 weeks.

Again, I cannot stress enough the importance of airflow. Even in a kiln, lumber will not dry properly with poor airflow. Drying wood is a passive process and it will only dry as fast as it can exhaust moisture to the air around it. Think of a scoop of sugar dissolving in a cup of water. You can dump it in and wait for half an hour until it dissolves, or you can stir it with a spoon and have it done in a minute.

Fans aren't necessary, if you can stack the lumber in a breezy area.

Also, don't forget to seal the end grain. If the wood is over 30%, you will get some degree of checking. The greener it is, the more you'll get and they'll travel deeper into the log/cant/billet/board.

If you're really impatient, you can cut the logs into 4/4 boards and sticker those with airflow for 1-2 months. Like I said, they'll drop surprisingly low, relatively quickly. It's getting it below 20% that takes a long time. But, there is a trick if you want to start working with it sooner. After letting the boards air dry for a month or so, you can resaw them to your rough set thicknesses and sticker them with chopsticks or any kind of small wood that will act as stickers. Rubber band the ends to minimize warping, then blow a fan on those, or put them in a climate controlled room or box for about a week. Even better, if you can blow a fan through, in a climate controlled room. Air conditioned rooms are great, since they dry out the air. In fact, most traditional kilns are basically ac units, with fans circulating air in a temperature controlled room. As long as you have good airflow and the humidity is right, you'll be able to drop them to 6-10%.

etkre
10-10-2009, 02:54 AM
Thanks Paul, I was getting a little bummed by the thought of waiting a year or two before I could get to shaping this stuff. I'm excited again! Quick question, will green wood damage the blade of a table saw? I don't want to mess up the saw at work.

RonS
10-10-2009, 03:11 AM
Etkre, do you have a kiln?

That's the key to drying it quickly.

etkre
10-10-2009, 03:17 AM
No kiln, but I do have a spare room that I could seal off and run fans and an A/C dehumidifier unit.

Moore Bettah Ukuleles
10-10-2009, 07:21 AM
Good advice Paul. Someone over here turned a shipping container into a drying kiln simply by installing fans and vents in it.
Or you could as I do and buy enough wood so you can get ahead of yourself a few years. I'm buying koa now that I won't use until after I'm dead.
BTW, do you use the sugar water before or after the wood is dry?

RonS
10-10-2009, 07:39 AM
Or smaller

Filing cabinet (or refrigerator) with a light bulb for heat and a vented fan.

Pete Howlett
10-10-2009, 07:55 AM
When Jeff traugott had that tremendous article published in acoustic guitar magazine he got orders for 10 years ahead. I asked him what he was doing with the deposits - answer: "Buying all the Brazilian Rosewood I can get." It's the luthier's curse - WAS. I really envy my hawaiian contemporaries - here in the UK I get the KOA crumbs from your table and boy do I have to pay for them :(

Moore Bettah Ukuleles
10-10-2009, 08:53 AM
When Jeff traugott had that tremendous article published in acoustic guitar magazine he got orders for 10 years ahead. I asked him what he was doing with the deposits - answer: "Buying all the Brazilian Rosewood I can get." It's the luthier's curse - WAS. I really envy my hawaiian contemporaries - here in the UK I get the KOA crumbs from your table and boy do I have to pay for them :(

It's no better here, the best stuff gets shipped overseas. A well respected builder here that we both know just bought 20 sets from the mainland. I've boughten sets before from Washington state that was felled just a few miles from my shop. If you're buying "koa crumbs" it could be that you're not willing to pay for the good stuff. The last koa I bought was $75.00 a board foot. Green!

Pete Howlett
10-10-2009, 09:30 AM
Oh it's very good but at $110 - $135 a board foot often sight unseen I've given up. Some good stuff occassionally crops up on eBay. Last time I looked at buying sets from Bart Potter it was $155 for mastergrade. That was 4 years ago. When it gets to my front door you can add 65% to that in shipping and duty! My only consolation is that when the dollar is weak I just hope I have some spare cash to buy. However, shipping has nearly doubled in the last 2 years. It's all a bit depressing...

Moore Bettah Ukuleles
10-10-2009, 09:38 AM
How about I send you some cheese?

Pete Howlett
10-10-2009, 10:09 AM
Do Hawaiians make cheese?

etkre
10-10-2009, 12:46 PM
I read that some people use paint to seal the endgrain. I have a gallon of latex lying around. Will that be okay, or would you recommend something else?

Thanks for all the info so far.
Eric

RonS
10-10-2009, 01:41 PM
I read that some people use paint to seal the endgrain. I have a gallon of latex lying around. Will that be okay
Eric


Yep, should be fine

etkre
10-10-2009, 03:02 PM
Thanks, I'll paint 'em in the morning.

Eric