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Bob Smalser
04-28-2004, 6:45 PM
RE: “Big Madrone” Posted Below



From 10 tons of 8’ logs…
http://pic3.picturetrail.com/VOL12/1104763/4110272/50978740.jpg

…the 240-year-old Pacific Madrone was milled into flooring, stair tread/threshold and turning stock, along with the flitches taken from the slabs…

http://pic3.picturetrail.com/VOL12/1104763/4110272/51164646.jpg

Madrone is a relatively unstable wood, benefits from slow drying, and a wide stack is made using 4/4 dry cedar stickers:

http://pic3.picturetrail.com/VOL12/1104763/4110272/52320534.jpg

On a small hilltop with good airflow, cedar slabs were laid on the ground and shimmed flat…not necessarily (or even desirably) level, but flat. For 8’ stock, three 4X6 DF bearers were laid square, and the flooring stock stacked in layers or decks tightly with the edges touching, followed by the heavier 5+/4 stair tread stock. Each layer of stickers is positioned directly atop the bearers, and the stack is laid to slope outward slightly as it gains height to provide shade. A few layers of beveled cedar siding top it to provide shade. Light builder’s felt or tarpaper will be applied just to the top surface later. Tarpaper, Tyvek, and some commercial products made for the purpose don’t condense moisture beneath as severely as plastic.

To slow down drying of the end grain to minimize checking, the log ends were painted with Henry’s Roofing Compound…tar in a water emulsion that dries like paint and doesn’t smear during sawing. The preferred product for this is a wax emulsion called Anchor Seal…very effective but also very expensive. This Home Depot tar at 3 bucks a gallon works as well and much better than common paint (by all means use any old paint rather than nothing) …but it adds a step. I’ll have to chop those tarred ends off before running this stock through the planer.

http://pic3.picturetrail.com/VOL12/1104763/4110272/52320504.jpg

The flooring stock is laid in a 8’ X 10’ stack for the first year. The heavier turning stock is stacked separately. This time next year, the center will be removed from the flooring stack…once the cedar cover is removed the stack doesn’t have to be dismantled, the boards will pull out…to make two, 4’ wide stacks. By then, the 4/4 and 5/4 stock will have reached its equilibrium moisture content of around 20 per cent and it will dry to below 10 per cent by September next.

Cedar can be dried in less than half the time of Madrone and other unstable hardwoods and Douglas Fir in a little more time than cedar.

The final tally for the tree was over 900SF of vertical grain flooring and tread stock and another 500BF of turning stock and flitches

Todd Burch
04-28-2004, 7:09 PM
Bob, I really enjoy your picture-filled, information-filled posts. However, I do not understand this comment:

"By then, the 4/4 and 5/4 stock will have reached its equilibrium moisture content of around 20 per cent and it will dry to below 10 per cent by September next."

By definition, wood reaching equilibrium moisture content (EMC) means that it has reached a point that the moisture content in the wood is equal with that of the surrounding environment. Around the Texas Guld Coast, our EMC is 11% to 13% EMC.

Once wood reaches EMC, it will "dry" no further, UNLESS, you change it's environment. Merely waiting another year, and not moving the wood, will do nothing to drop the moisture content to 10% if your EMC is 20%.

I'm no expert by any means, but I do have a certificate from the Univ. of Tenn. @ Knoxville telling me that I was present for 3 days of wood drying class a couple years ago. :) (Whatever that is worth)

Todd

Bob Smalser
04-28-2004, 9:10 PM
Correct, Todd...and thanks.

But here EMC is in the 20pct range in late winter and the 8-9 pct range in late summer. Yours is obviously different in Texas.

I'm being sloppy in my terms. What I mean is that when the wood goes from the green M/C in the log...say 30-60pct...to in the 20-22pct...the bulk of the shrinkage and instability is gone and it is no longer fussy about sticker position or weight and is safe to move. Wood is never completely stable, but once it gets down to close to 20 pct, I'm ready to take it to the next stage in drying...the final stage, of course, is stacked in the heated shop often on end in a rick.