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View Full Version : Time needed to air dry Port Orford Cedar?



dmede
07-08-2004, 11:39 AM
Ive got some old growth POC thats been drying for 3 weeks in my garage and was stickered for most likely 1-2 weeks at the lumber yard. Its all 4/4, various widths and lengths. A set back with my WRC bulkheads has me left with nothing to do so I'm itching to start the midframe and stems of my Fiddlehead canoe but am worried the wood is still too green.

Any opinions on time needed to dry the wood properly? And what is the cheapest method to test the MC of the wood (if thats even neccesary)?

Thanks,
Dave

Bob Smalser
07-08-2004, 09:20 PM
Milled in early June?

Have a woodworker friend with a moisture meter?

1 October or 13% M/C...whichever comes first.

dmede
07-09-2004, 10:54 AM
yipes! I don't want to wait that long :( I'm not sure of the milling date so maybe I'll have to call them. Do lumber yards ever test M/C of small peices for you, you know if you bring it in?

Ive read posts (but now cant locate them) about checking a small peice in the oven... anybody with the procedures for that? bear in mind that I would have to buy the scale needed to do the weiging.

Bob Smalser
07-09-2004, 11:02 AM
Moisture Content – Oven Test

You can test your M/C with modest accuracy in the oven using a postage scale without the ambiguity of wondering how accurate your meter is.

Just get a starting weight for a small chunk from the middle of one board, cook it til it stops losing weight, then compare the before and after weights.

Moisture content = 100*((Initial Weight - Dried Weight)/Dried Weight)

http://www.woodweb.com/knowledge_base/Eliminating_Wood_Problems.html

http://www.woodweb.com/knowledge_base/Eliminating_Wood_Problems.html

All I care about boat wood is whether it is stable to the outside air yet. That range is generally from 13-18pct M/C depending on where and what time of year. Dryish woods like D. Fir and WRC are about 30pct M/C in the log cut during winter, and stabilize to about 20pct here by early June...and I can tell the difference well enuf between green and dry by the weight and feel of the board.

By the end of September before the rains begin, that same stock in 5/4 or smaller is at 15pct or lower.

So I know that June wood is gonna shrink some by September and that September wood is gonna swell some by 1 December. And I plan for it when building with it. How much do I plan for? Check out the USDA Wood Encyclopedia for the wood you are using. Cedar doesn't move much at all with seasonal changes....while Doug Fir does, so planning for the movement and using q-sawn stock becomes more important.

Thicker stock takes generally one drying season per inch of thickness to stabilize....with cedar much quicker than that and maple a bit slower.

Furniture or other indoor wood I simply roughcut and restack and sticker outdoor-stabilized stock indoors for a few weeks before using....cedar a week, DF two weeks and maple three weeks. Gets it to around 10pct....which works fine except if you set the finished piece next to a heater during winter, where it will dry to 6pct or so. And that can be planned for too.

Spissgatter W-9
07-13-2004, 09:41 PM
When we re-hung planks, the shipwright I retained bought the old growth doug fir salvaged by some gipo from a log that had been submerged in a lake. It was plenty wet. He had it milled to 5/4, stacked on stickers in his garage, covered with plastic and put a rented dehumidifyers at one end. Seems to me he had it dried down in a 4-6 weeks. This may be an option.
geo

Bob Smalser
07-13-2004, 09:54 PM
had been submerged in a lake Pond salvaged wood has already lost most of its cellular water...it's the water between the cells that sinks it. The cellular water is the slowest to leave...so submerged wood dries almost as fast as airdried wood left out in the rain for a good soaking.

Green wood straight from the tree takes longer.