permaculture

[Mikal Jakubal <mjakubal@asis.com>]

HI,
Sorry to take so long to reply, but your message got buried by the flood of
emails from other lists (gotta set up filters...) and I only just saw it
again while clearing out old stuff.

>have two very large (but near dead) white ash trees milled into large beams
>for a timber frame structure. I understand ash (like oak) will twist, warp,
>bend alot when drying so was looking for ways to mill it to preserve it for
>long term use, and use it as efficiency as possible.

How much a board will deform when sawn and dried depends on a number of
factors, the most important being the quality of the log, how it is sawn,
and how it is stacked and dried. If the tree is straight, with no reaction
wood (when it is cut down, look at the butt--the heart should ideally be
centered and the ring density equal all around) you'll be off to a good
start. Make sure you don't split the heart when sawing it. The heart should
end up centered in a beam. If you want your beams to be clear, once you get
toward the center where the knots are, you could cut 4/4 or 5/4 boards and
make flooring out of them. Knots are okay in flooring if you don't mind a
slightly rustic look. To stack, make sure the pile starts on a flat, level
surface and sticker the beams every foot or so. If big beams want to twist,
it will take massive amounts of weight on top of the pile to prevent this.
What I use is barrels of water. Put a layer of stickers across the top of
the pile, then a row of 2x4s to help spread out the weight. Then put 55
gallon barrels up there--as many as you can fit--and fill them with a hose.
When it's time to empty them, use a siphon hose. Keep the pile covered and
out of the rain and sun. Sun and too fast drying will destroy wood quicker
than anything. Ash 9x9s will take years to thoroughly dry--how many, I
don't know--it depends on your climate.I've never done timber framing, so I
don't know how dry you want them to be. 


The sawing part is trickier to explain. The best advice I can give you from
here is to get and check references of sawyers. There are a lot of people
out there who just got a mill and can make a 2x4, but don't really know how
to read and saw a log for maximum value. There are also lots of old-timers
who use outdated and inappropriate sawing techniques. Point is that
experience alone is no guide to quality. My usual advice is to find local
fine woodworkers and ask them who they'd recommend. Fine woodworkers rarely
have money to waste AND they really know what the best quality wood in a
log is. So when they hire someone to saw one of their valuable logs, they
make sure it is done right--and they know what "right" is. When you find
two or three furniture makers who recommend the same person, that's
probably a good sign. 

If you can't find any sawyers through references, you might call Woodmizer
(the kind of mill I've got) at 800-525-8100. They ought to be able to refer
you to some Woodmizer owner in your area. They may also know about other
places to look for sawyers.

By the way, sawing the beams oversize is a good idea, but it would be
easier to re-saw them to size with a band mill once they are dry. Running
something that big through a planer and joiner would be a tough job. I
would only go 1" over size to minimize waste. On the other hand, by going a
couple inches over, you may be able to do a thin skim cut on one side, and
get a board thick enough for flooring or cabinetry from the other.

The USDA Forest Products Laboratory in Madison, WI has lots of books and
pamphlets on sawing, drying and so on. They should be in the telephone
directory. I bet they have a web page too.

Hope this helps.  

Mikal