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Michael Smith
11-14-2011, 10:48 PM
I I've been sawing and resawing quite a bit of black, and silver acacia and myrtle. I resaw as much as I can stand as soon as I get it and set the rest aside. I find when quickly resawn the ends don't even check. As Rick as said in another post it seems to work better when cut to sets as soon as possible. I have been having a problem when resawing the green black acacia my blade loads with pitch which causes the blade to vibrate and wander if I don't run a razor knife along side of the blade to cut off the hardened pitch every 10th cut or so. Does anyone have a fix for this? Black Acacia seems the worst offender. My saw has a built in brush on the blade but it doesn't seem to help.

I'm also wondering about how long after cutting the wood to 1/8th" would it be usable. If green wood takes 1 year per inch to dry does that mean 1/8th" would be usable in 6 weeks? Not saying I would try to build an instrument in that short a time. But when you read that a set has air dried for 2 years it really matters how thick it was during that 2 years. If it was in the form of a 2 inch thick billet that would not be any dryer than an 1/8th" piece at 6 weeks. My theory for what its worth is that it is very beneficial for the wood to go thru as many humidity variations as possible.

Allen
11-15-2011, 01:36 AM
Don't know what species your are referring to as Black Acacia. In Australia, Blackwood (Acacia Melanoxylyn) is usually cut green and depending on where it was grown can be easy to down right tough on blades to cut. A mate that does a fair bit of resawing uses paraffin wax on the side of his blade after every few cuts. Just a touch with a candle on either side of the blade while it's running. Seems to help.

Another mate that cuts a lot of Blackwood very green hangs his pieces from the cloths line as they come off the saw, just to get the initial wet off of them. An hour or so latter he stickers them in the usual manner and weights them down to keep them flat. I must have 40 guitar sets from him on my shelves. All perfectly flat without a single check.

I really don't care how dry they may be after a few months. They could be usable but I don't build with them for at least a couple of years.

mrhandy
11-15-2011, 04:16 AM
I have a can of paste wax that site in the tool trey in my bench, it has a bit of rag that is loaded with wax. When I am hand planing I will take the rag and wipe the sole of the plane every once in a while, I also do this with hand saws if i am having issues. I would think wax would also help on the bandsaw... I would think that a stick of wax would be safer to apply to a running bandsaw blade... ?The only other solution i can think of would be a wider kerf to help clear the waste, but if it is sticky you need something to keep it from sticking.

The year per inch rule for air drying wood is generally good for one inch stock, but once you go over that first inch the time can increase significantly. 2" stock can take 2.5 to 3 or more years depending on species. All air drying is dependent on climate. Here in Florida you can dry a board for 10 years and it will never drop below 10% unless you bring it into a climate controlled area. I have been known to experiment in my young instrument building career with drying wood. I dried a soprano set of eucalyptus in my black car in a few weeks.

Allen is right about letting the wood air out before stickering and stacking the wood, some species need to oxidize for a few hours before they are stickered, otherwise they will develop a sticker shadow that will not sand out. Also certain woods are quite susceptible to fungus, and if you sticker them with a damp surface they can be ruined. Dry wood is happy wood. :)

Rick Turner
11-15-2011, 05:36 AM
Allen, the black acacia we have here is indeed Acacia melanoxylon...aka Tasmanian blackwood, etc. It was brought over from South Australia or Tasmania in the 1880s and planted in Southern California as a fast growing ornamental. Our climate is very favorable to the trees, and they have spread on up the California coast at least up into Mendocino. The trunk quarters I just got were from a tree that was about 34" in diameter "at breast height".

I'm sawing using the TimberWolf 3/4" variable pitch blades, and I'm happy with the results. Try a bit of "Pam" sprayed on the blade every now and then.

Michael Smith
11-15-2011, 06:52 AM
Thanks for the info I'll try the Pam and wax. Yes this is the Acacia melanoxylon, It does look a little different than the sets I bought from Tim Spittle of Australian Tonewoods. It is quite a bit redder. It came from a very old tree just a few blocks from the beach in Santa Cruz, CA. I was thinking the salt air might have something to do with the redness. There is a project here in the SF Bay Area to plant Koa trees in California. Does anyone know how that project is going?

ukulian
11-15-2011, 10:39 AM
In all the years I've been cutting wood, both with machine tools and hand tools, there has always been one or two pieces of candle in my apron pouch. It's the next most useful item after a pencil. It gets used on planer tables/soles, bandsaw blades, router bases, even circular saws, although not on the actual blade in that case.

Rick Turner
11-15-2011, 03:01 PM
Planting koa in California (except for all the "only native trees" crowd) would be terrific! I would hazard a guess that it would grow quickly and well here. Acacias are considered a pest tree by some, but bring 'em on!

There always seems to be a "terroir" issue when a wood goes from one micro-climate and soil composition to another, though. The wood color may not be quite the same, etc. That said, though this acacia I just got is pretty plain, it's also really beautiful. I just need a good couple of days with nothing to do but block it out and resaw it. I am wishing I had a WoodMizer sawmill now. Many of these chunks are too big to deal with on the resaw, as large as it is.

Michael Smith
11-15-2011, 07:15 PM
Her is a little youtube about the guys planting the koa trees in Fremont Ca.
http://www.youtube.com/watch?feature=player_detailpage&v=hqQLDX1RYyA The ones that were in a year look like they are doing very well.