8X4 3/4" pine sheets cupping

Jnealon

I got some pine sheets a while back to make up some wide door frames. I have about 10 - 12 sheets left and noticed that they are starting to cup.
A chippie up the road from me asked me a while back could he swap a few sheets for some 1/2". I gladly said yes as I could use the 1/2" sheets to make up some door stops but now I doubt he will want to swap.
I have two questions
Can these sheets be straightened?
If he does not want to swap could I use the 3/4 inch to make the stops or is it a bit on the thick side?
The door stops will run the width of the frame minus the 44mm of the door.

Jim

boysie39

Jim I'm afraid I wont be much use to you as regards answering your question as I'm only new to woodworking. However before I became involved I spent months reading the threads and marvelling at the ideas being thrown around by what I took to be experts.Not being used to this kind of thing I dared to reply to a question that I had a small bit of experience with,It was only later I discovered the question had been posted in 2005.So I dont know if you will get an answer, I hope you do because I would like to know as well. There are lots that I would like to ask as well but they would probley be too simple to get people fired up to give an answer.Sorry I cant be of help to you because I see your from my birth place although I'm long gone now. Maybe one of the experts might pick up on it soon .Best of Luck boysie39

carpainter

Jim
As you've probably guessed by now this forum is extremely busy! I'll try and throw a few answers your way. I think 3/4" is a little too thick for a door stop/ rebate. Standard door stops/ frame rebates are generally 12mm or 1/2" thick. Again it depends on the frame and door style, perhaps a bigger door could handle a chunkier door stop but there is one other consideration- most door ironmongery (knob type "handles" in particular) are designed to function with a door having a 10- 12mm rebate or stop. Of course if you have access to a thicknesser..... As to whether you can "de-cup" your bowed stock- it's possible but whether it's worth the effort is debateable. If the stock was a nice hardwood it might be worth the effort. In any case what I have seen advised is to lightly dampen the stock with water and lay the boards flat on a flat surface- like a smooth concrete floor. Weigh down with some ply and concrete blocks and allow to air dry for a few days. hopefully the boards will recover. The alternative is to plan cutting of the stock to recover the most useable material and accept that there will probably be a lot of waste.

JoeB-

Hi
Yeah, I use a lot of pine boards and I find that once cupped, they are very difficult to work with, and dangerous. The panel tends to close on a rip cut or saw cut so a circular saw binds and kicks back and a panel saw can also have problems.

The panels can still be used for many things... just not very large items.

The panels have to be stored flat, never leaning on end against a wall and also covered with plastic and weighted down if possible.

Cheers so
Joe