Every time I start a project I am always concerned that my lumber (post
jointing and planing) will twist and bend before I can construct the
carcass. For my current project I am stacking my lumber with sticks in
between to allow for even moisture equilibration.
Should this be a 'real' concern? Or am I being overly cautious now?
Actually the process begins with timber selection. It is considered to
be good practice to select out the most stable stock (ie: as near to
quartersawn as possible) for the door frames and such. It is usually
considered to be best to do the stock prep and joinery for these items
on the same day, as the reference planes can become out of spec quickly
and the joinery needs to be cut before any relaxation can occur. A
secondary consideration would be the selection and preparation of any
exposed members such as casing and pilasters. If your carcase is to be
of solid stock it would be best to joint and glue the panels on the
same day, for the above reason. The stickering of stock should occur
during the stage that the timber is in a rough state. You will do
yourself a great favor if you bring the timber to final dimensions and
create the joinery on the same day, whenever possible. If you do not
do this, you run the risk of your reference edges becoming out of
square to each other and your joinery will be the worse for it. The
concern for Equilibrium Moisture Content is most perfectly put at the
rough timber stage. If you remove more or less equivalent mass from
the opposing faces during prep, you will not have to worry about
distortion from unequal moisture content throughout the section.
Are you concerned because of a bad experience? Sure, it's a real
concern, and no, you're not being overly cautious, especially if you
live in a humid environment. Stickers are part of it, of course. Use a
two-step process of machining. Acclimate the wood to it's final resting
place, rough dimension, allow to acclimate and move again (as long as
possible), then final jointing/planing/assembly/finishing (as quickly
as possible). I think. Tom
I agree with the above replies. Also, if you get lumber from a mill (I
have my own logs milled) try to keep all boards, from the same log,
together and keep the boards adjacent to one another, as they are sawn.
Before milling, try to mark the ends of the logs so that you can tell,
after cutting and if the boards get separated, how they were positioned
within the log...Does that make sense? It's best to have similar boards
complement one another, within a woodworking project.
All experienced woodworkers are well aware of the "living aspect" of
lumber. It moves, twists and bends. It is best to true up your
lumber and cut to size shortly (at most a day or two) before assembly.
There are many factors that can effect cup, wane, and warp.
This answers another question I had. A couple of days after getting it
home, I noticed that some of the cherry I bought earlier this week was
slightly bowed. I wasn't sure what happened.
After reading this thread, it seems that you guys are saying that this
is going to happen, and it's just part of working with wood. Is that
ukalu wrote: >This answers another question I had. A couple of days
after getting it
Yep, it's part of it. Certain woods are well-behaved, others are not.
And it depends on a few other things, such as where from the tree the
wood was cut, changes in temp/humidity, storage methods, etc.. Tom
On 20 Jan 2006 06:55:07 -0800, email@example.com wrote:
How did you buy it ? I'd expect it to move after cutting or long
drying, but rapid movement of unworked timber is indicative of timber
that wasn't quite as dry as you might want it. If you brought it from a
damp winter timberyard into a warm, dry house then I'd expect it to
move, but not if you left it in a draughty workshop.
Which way did it go ? Did the rings straighten out (getting drier) or
did the rings curve more (getting wetter) ? If you really want this
cherry to give you the results that cherry is worthy of, let it sit for
a few months in the sort of humidity it'll finally be stored in. Better
have it move now than after you've made the cabinet.
Couple of things you might like to look at:
A couple of cheap (<$5) plastic air hygrometers. Put one in the workshop
and one in the living room. Keep a vague eye on them around the year.
Bruce Hoadley's excellent book "Understanding Wood". If you want to be a
_good_ woodworker, you have to get a little grip around this stuff.
The US forest products lab handbook. This is available for free as PDFs
on the web, or you can buy an affordable paper copy from Lee Valley etc.
Thanks to all that responded.
My only problem with some of the responses is that I cant always (actually
never) assemble a day or two after milling. I woodwork after work in the
evenings a few hours at a time and then on weekends. It is sometimes (ok,
always) necessary for me to leave stock for several days after milling
before assembly. So far I have only 'noticed' a problem once, where a board
cupped slightly and needed to be re-face-jointed.
I cant be alone here.?. Is everyone assembling a day or two after milling??
Copied from an exceptionally well written prior post:
It is usually considered to be best to do the stock prep and joinery for
on the same day, as the reference planes can become out of spec quickly
and *****the joinery needs to be cut***** before any relaxation can occur.
Being a bit anal here but it's cutting the joinery here that is most
critical, not assembly.
I think there is a subtle but important distinction.
If I can possibly avoid it, I would never intentionally make major cuts
on timber then carry on working with it immediately. Leave it a week
after you resaw it before thicknessing. Leave it a week after
thicknessing before you do the joinery. I've usually had the raw boards
in my own racks for a few months before I work it anyway.
For assembly, then I'd prefer to assemble as soon as possible after
cutting joints, but I really wouldn't sweat it. The timber should be
more stable by this point.
This is probably why I have a great many projects on the go
simultaneously and never get to finish anything!
Interesting post and responses.
Just to throw my two cents into the discussion....
I've never gone with the approach to hurry and 'get er dun' before the wood
starts to move. What's to stop the wood from moving after it's assembled?
I normally mill my stock down and leave it oversized in thickness and width.
I let the stock sit on edge with no stickering or stacking for a few days
and let it move were ever it wants. Then I joint two adjoining surfaces
square and plane the stock to it's final dimension. If the stock moved too
much to use this method, I really don't want to use it anyway as it would be
the piece that racks the project. For interior door stile and rails, I will
oversize the glued up stock by 5/16" and let it sit without pressure for a
month or more.
I would rather have the wood move before I machine it rather than after.
Just another method to consider.
As usually Tom, the correct answer. Thinking back on what I said about my
wood moving when doing rails and stiles on interior doors, I had actually
forgotten why I try to assemble the doors quickly after cutting. I
indicated that the wood would bow after cutting. Actually after thinking
about it I seldom have a piece bow. The actual problem that I have is when
I cut the groves in the rails and stiles for the plywood panels to fit into.
In humid Houston if I do not assemble the same day I often have to taper
the edges of the panels with a sander so that they will again fit into the
slots in the rails and stiles.
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