Mine cup overfloweth

[PerranOak]

So, I bought two ash planks and let them acclimatise in my "shop".

Now they are cupped.

I did leave them "taped" together, thus one side was covered, one exposed - the "shop" is quite dampish.

Will this cause the cupping? They were ok when I got them and they'd been in the supplier's store for ages.

Will they go back now I've separated them?

Cheers.

 

[wizer]

How odd, you taped them together? It looks like you understand why they've cupped. It's unlikely that they will go back to flat on their own. You'll have to plane it out and hope you've got enough thickness.

For future reference. Store wood with stickers between each plank running perpendicular to the length. This keeps the air flowing around them and the drying even. Stickers can be made out of MDF or PLY aswell as solid wood. Obviously they all have to be the same thickness or the wood will deform.

Oh and if it's still not clear DON'T TAPE THEM :roll: :wink:

 

[Digit]

Will this cause the cupping?

Yes! DAMHIK!

Roy.

 

[OPJ]

Yep, it's basically it's probably because you denied one face on each board the chance to ventilate and release/take on moisture at the same rate as the exposed face.

Are these boards sawn or have they been planed all round?

Chances are, they will want to move again now that both faces are 'free'. Whether or not they will return to being 'flat', God knows! :shock: But, they will quite possibly move.

 

[PerranOak]

Darn!

Thanks all.

The timber yard taped them together and I didn't separate them!

They are planed all round.

They will become drawers that are a little bendy I guess as one board is too thin to plane really. The other is thick enough and, I guess because it's thicker, didn't bend as much.

Lesson learned! :roll:

 

[squib]

It may sound a bit drastic ..............but if you put them on a concrete floor and chuck a bucket of water on them they should straighten out again, i was told this by an old gypsy wagon builder and have done it a couple of times with great success.

 

[woodbloke]

The Golden Rule - always treat both sides of a board in the same way - Rob

 

[PerranOak]

I guess I didn't think it would make so much difference so quickly. There must be a huge humidity differnce between the Timber shop and mine.

I really need to use this wood - I'll even throw a bucket of water on it if that'll help!!?!?!? (... did you really mean that squib?).

I've already cut out four pieces ready for the drawer in the hope that they'd "spring back"!

 

[wizer]

I think I read somewhere about leaving a board on grass over night and the dew in the grass will even the board up. Sounds like an old wives tale to me. Go get yourself some new boards and put it down to experience. These can be used but will need considerable flattening and you will probably yield more by ripping them for smaller components.

 

[squib]

Yes,I do mean it but only if the boards are bowed lengthwise.If so i think as the boards are already planed i would damp down the flat concrete and put the boards on it...put the curve so that the two ends touch the concrete and the bow is upmost.....the logic is that one side of your timber has dried and shrunk more than t'other so damp concrete causes a that side to swell .Try it overnight and see, i think that if you dont wet the boards there is nothing to lose. I even got a friend to try after he had carved and guilded a house sign that warped and it worked a treat.These are my thoughts and as a newboy i am losing a little confidence as i type because i dont fully know the beauty or quality of the timber so maybe only as a last resort.....good luck with it anyway.....I'll get me coat!

 

[PerranOak]

squib, I didn't see your post before I did this:

I put an old towel soaked in hot water on them and left them over-night. Now one is 20mm thick, the other 10mm.

I was atonished!

The thicker board is now flat!!!

The thinner one is cupped!

However, the thinner one is now cupped THE OTHER WAY! :?

I guess it worked too well. Now I'm trying to "bend it like Beckham" ... just right!