Hi Niels



 > They vary from dead straight through simple curves to zigzags. A

 > depressing little paragraph in a "Furniture Making" book tells me

 > that proper drying out (60% water to <20% ) can take up to a year.

 > Bloody hell.



 NP>  The REAL figures are 1 year for every inch of thickness. I.E a 4x2 will

 NP>  take 2 years to dry out _properly_!



Bummer. I've made this nice set of cupboards and drawers, all built

and sitting loose on the base, waiting for a top. They're in use as

a fast-access fast-tidy toy storage, and if I wait too long before

adding a top I'm going to get loud complaints cos it's suddenly too

hard to get into the top drawers.



 NP>  Using them at less than 20%

 NP>  moisture figure (used for kiln dried) will result in some further

 NP>  shrinkage after they are in situ which will leave noticable gaps.

 NP>  For a good finish you need them _fully_ dried.



I don't quite understand - do you mean that a too dry timber can

give problems similar to wet timber problems?



 NP>  The above figures are for Tasmanian hardwood so I figure they would

 NP>  apply for most hardwoods.



Sounds right.



 NP> For air drying, the timber needs to be stacked level and straight, with

 NP> at least a 1" gap between each board and each layer separated
by 1"

 NP> thick separators.  If the separators are laced about a foot apart and

 NP> the stack is of sufficient size, the weight of the timber itself will

 NP> reduce the warping and twisting to a minimum.



I heard a radio article on the subject just a few days before I

read this, kicked myself, went home and stacked the planks. I'd had

them just standing on edge, and two of the 13 were warping visibly.

They're now in a spaced stack, with a few bricks on top. The garage

floor should be reasonably level over the 2 metre length of the

planks (though it certainly isn't over its full area). The spacers

are about a metre apart, though; I'll put in some more after

checking that the planks are reasonably even in thickness.



 NP> I found a rule of thumb figure was to get 30% more timber than required

 NP> and you will wnd up with enough straight stuff for the job.



Could be a bit tight; I'll need about 6 planks for the job, and a

few of the 13 are a bit thicker than the rest.



 NP>    I was told

 NP> this figure by an old timer, and used it to purchase ALL the timber for

 NP> the house when green.  I racked and dried all the timber I required as

 NP> dressed timber such as barge & fascia boards, door frames, mantel piece,

 NP> exterior wall cladding and also all the timber for the window frames

 NP> (Lounge windows were floor to ceiling).



 NP> The old guys estimate worked out to be pretty well spot on, with the

 NP> warped stuff being used as noggins etc.



 NP> I dressed the lot after after about 2.5 years and had NO movement or

 NP> gaps at all.  Dressed kiln dried was complete loss for anything except

 NP> the rafters and purlon for the 6 square carport.



 NP> I know that 2 years seems a long time but it is worth the wait if you are

 NP> doing something like laminated timber bench tops.



You've convinced me. I'll make a temporary top for the cupboard

while the good stuff dries.



I saw a program on telly about this quite a while ago - a

woodturning mob (a company or a school, I can't recall) found that

if they microwaved (as in microwave oven) newish timber, it would

become well-behaved timber, just as if it had been aged, and could

be safely lathed into bowls or table legs or whatever. I don't

think I'll find a microwave oven around here that can take 2 metre

planks, though...



 NP> The only timber I bought already air dried was for the staircase I built

 NP> in a later house and some 3x2's that were Blue Gum railway sleeper

 NP> offcuts.  (The Blue Gum HAD to be drilled just to get a nail to go in)

 NP> :-)



sounds familiar. Self drilling screws don't work in this stuff,

either.



 NP> Best of luck ;-)



Gee ta. I have a secondary project now, a barbecue stand, that will

use some of the planks I can't use on the benchtop. I plan to cut

one plank into 500 x 60 x 15mm slats for the tops. I've seen thinner

offcuts of this stuff warp like crazy, I'm about to learn if 15mm

thick bits, screwed down at both ends, will warp...



Here's a semi-related question - is there an economical way of

buying or making a 2 or 3 metre long straightedge?



Cheers, and ta for advice



--- PPoint 1.88