having problems with pine warping

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thetyreman

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Hi,

I bought some 6 x 1 PAR redwood recently and they've both warped already within less than 2 days, from being perfectly flat originally,

the problem with it is I need very straight pine for the sides of a bookcase, however they seem to move regardless of what I do, it's my first piece of furniture and it's going to be a gift for a relatives birthday present, the pieces are around 40 inches long and there will be a dado joint that they go into, if they are warped like they are now, they won't fit in the dado joint, that's the problem.

what do you all recommend? I would like to hear your opinions on how to minimise it or stop it as much as possible,

cheers.
 
buy it oversized, let it acclimatise inside and then machine it to size, bit by bit if you need to.
 
marcros":3muu0wqq said:
buy it oversized, let it acclimatise inside and then machine it to size, bit by bit if you need to.

I don't have any machines, using hand tools only, when you say oversized, by how much? like 8 x 1? I'm not sure the timber yard I'm going to sell anything wider than that.
 
here's the current weather report
 

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thetyreman":3fyhg7sh said:
marcros":3fyhg7sh said:
buy it oversized, let it acclimatise inside and then machine it to size, bit by bit if you need to.

I don't have any machines, using hand tools only, when you say oversized, by how much? like 8 x 1? I'm not sure the timber yard I'm going to sell anything wider than that.

if it is cupping, then you will lose some thickness correcting it- so 7x1.5 or so, if you can get it.
 
Use quartersawn material .
Use flatsawn material .
You might try dampening the concave side of a board if its not too bad.
How are you storing it ..If lying flat the moisture from the air will go into one side only.
(depending how dry of ,say a table that it's laying on) alternate often.
If you can't get either choice of grain orientation, rip the boards into pieces that will yield stable material
and laminate up to get what your looking for .
Lots of gluing though .
If you still cant get stable material after ripping, alternate the timber ....
So, if you were looking at the laminated end grain,
you would see smiley mouth,sad mouth,smiley mouth.sad mouth,exc
This might be your only solution, and you might still need to put weight down ,
You will get a rippled effect, but its better than nothin .

Or salvage as much superior materials as you can,like doors ,windows and the like
Even if you were choosing softwoods, I'd still be lookin for salvaged free stuff.
Buy a jack plane for Gawd's sake if you don't have one allready .
And the most grimy undesirable timber to the layman suddenly becomes way superior than
any softwood you can buy ...within reason .
A quick lick with a hand plane transforms the ugliest stuff into stable material, that has allready warped
90% as much as it will, because it was stressed in use for years being a door or whatever .
I have more hardwood now, than I could not shake a stick at !
As I'd never be able to afford any wood wherever place it be .
And its all pretty stable, so much so that I can choose only the best for a bench top....
Which you will be sick of me talking about in time :roll:
I bought a lumber wizard style metal detector for nails and screws and this has proved sooo useful .
Good luck
The ugliest ,weathered, nail ridden timber often turns out to be the best, unobtainable timber,
Regardless how thick your wallet is !!!
A thread I will be posting about very soon
Good luck
 
I'm writing this without seeing the actual wood you have, but in my experience you can, to some extent, use non-straight wood to make a straight piece of furniture. If you can easily straighten your side pieces by bending them in your hands, you might be able to constrain them into shape.
You will need to have some big cramps when assembling, or improvise some.
You might need to clamp some temporary stiff battens to help components stay straight.
Another option is to nail your housing joints. If you use small nails from under each shelf, going up into the ends at a slant, they won't show at all.

You don't say where you are storing the wood. Especially at this time of year, bring it into a cool room in the house and only take it out to the shed while you are working on it. As advised, expose both faces to the dry air.

Good luck!
 
PAR is not suitable for furniture as a rule. It's for bodging only. For people who don't have the kit.
You need to buy sawn boards and plane them up yourself.
marcros":3fnuzqjz said:
buy it oversized, let it acclimatise inside and then machine it to size, bit by bit if you need to.
Everybody needs to do it bit by bit! That's how you do it.
You never plane anything until it has been cut to length and ripped to width - with a margin for error, allowing for horns etc. Except very short lengths which would be easier to handle as one longer piece - but not too long.

Set aside the straightest stuff for the longer lengths and vice versa.
 
Jacob":3csbvgeg said:
PAR is not suitable for furniture as a rule. It's for bodging only. For people who don't have the kit.
You need to buy sawn boards and plane them up yourself.
marcros":3csbvgeg said:
buy it oversized, let it acclimatise inside and then machine it to size, bit by bit if you need to.
Everybody needs to do it bit by bit! That's how you do it.
You never plane anything until it has been cut to length and ripped to width - with a margin for error, allowing for horns etc. Except very short lengths which would be easier to handle as one longer piece - but not too long.

Set aside the straightest stuff for the longer lengths and vice versa.

What I meant by bit to bit was to get somewhere near final dimensions, and let it sit for another day or two to see whether it will move further.
 
I think it's likely that your problem is in how you're placing the wood once you get it home and it's getting wetter or drying out unevenly, which is a classic problem if you're placing wood flat on a surface where air can't get to one side, or up against (doesn't have to be touching) a cool wall. And it can happen as easily to wood that's fully acclimated to your workspace (been there for months) that you've just completed planing to thickness as to wood just bought in, so it's something to always bear in mind.

If you're storing the wood in the workshop to minimise the risk the two best courses of action I think are:
  • Store the boards until you're just about to use them stickered and under weight. This way the moisture content of the wood can change fairly evenly, with any slight tendency to warp taken care of by the weight.
  • Store the wood until you're just about to use it well wrapped in plastic bags (a black bin liner is perfect if large enough). This way it's kept in a stable environment and can't dry out or get wetter.

Buying better wood can help, since flatsawn stuff is prone to this sort of problem. You can get lucky sometimes buying cheap softwoods to find individual boards that have rift or quartersawn grain – like this at the end /// or ||| – and if there's any of that you should get it in preference to stuff with flatter grain, it'll always be more stable.
 
got it, thanks guys, it's very likely to do with how I was storing it, I had one end on the floor, and one end in open air, but now I've got them on my sawhorses with both ends exposed to the air, it seems to have moved back a bit to being flatter, actually it's not as severe as it was yesterday, I've certainly learnt a lot from all your responses.
 
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