Board Cupping in relation to thickness, much change over 1"?

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Tetsuaiga

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I was just wondering about board cupping as i've been thinking about trying to make a table, perhaps a two part slab type, so board about 35-40cm wide.

It seems safe to say thinner boards will tend to cup more than the thicker ones, but once you go over 1 inch thickness do you think it makes much difference?

I'm just looking for opinions really.
 
Tetsuaiga":z20l4vq6 said:
I was just wondering about board cupping as i've been thinking about trying to make a table, perhaps a two part slab type, so board about 35-40cm wide.

It seems safe to say thinner boards will tend to cup more than the thicker ones, but once you go over 1 inch thickness do you think it makes much difference?

I'm just looking for opinions really.

The species, moisture content and the grain are possibly the most important factors in cupping more so than the thickness.
look for quarter sawn timber, which is more stable, but can limit you're budget by sheer cost, and you may find the grain noy as interesting.
When facing and straightening, say, on the overhand planer, it's important to try and reduce the material as equal amount as possible each side thereby, hopefully, not adding more and different stresses.
There's a lot to be said for cutting the top in half, in width, and then joining back together after straightening/ planing as it's less wasty, as you have straightened smaller sizes plus addressed the stresses by cutting and using a decent glue should make an almost seamless joint.
There's some members on here, who have better college memory retention than I, whom will give you their thoughts all pretty good stuff, you'll find! Regards Rodders
 
Over the width you are planning I would suggest that some cupping may still occur even on thicker boards. The nearer you can get boards to being quartersawn the less chance of cupping. And the longer you can leave them to acclimatise before working them the better.
 
Thanks.

If you were to do the rip in half method do you join back after flipping one side over?
 
Tetsuaiga":2a8uxs82 said:
Thanks.

If you were to do the rip in half method do you join back after flipping one side over?

No, I kept the same side as the grain needed to match as in a table top,
Regards Rodders
 
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