I have these 9”-wide, 3/4”-thick pine panels from the bigbox store that i would like to make into a carcass with dovetails.
Such panels commonly exhibit some cupping, but have some spring into them, and can typically be flattened with clamp pressure.
Would they stay flat once joined with dovetails? or does stock need to be absolutely flat from the start?
Photo shows three panels with varying amounts of cupping. A second clamp, if placed in the center, makes them flat again.
I gave it a go with the panels, based on feedback here. And it's totally fine, plus or minus some adjustments. This was my first attempt at dovetails. Here's a few things I'd not realized until I had to actually do it.
0) A bit more planning on my part would have revealed that the pin board (which was a glue-up panel) also had some cupping in it. So I had to clamp the two boards flat simultaneously while scribing my pin board on the tail board, which did complicate the clamping and marking situation. The tail board was clamped flat with a vise (a workmate), and I was holding the pin board vertically, with a 2x4 clamped on the piece to keep the pin board straight.
1) Depending on the level of cupping in the grain of the tail board, you end up with somewhat weak tail corners. I unfortunately didn't pay attention to that when I did the layout. I designed pins first, but didn't double check where the pins landed before committing to their final shape. I also should have pared more carefully around these fragile corners.
2) I put the heartside facing outwards of the box, as was recommended. But I still ended up with a minute gap. I've shone light through the gap here. There is some spring still in it and it won't rest at the bottom without pressure -- maybe my joint can be cleaned up a bit more. I feel it will probably vanish, with clamps and glue-up.
And the overall look:
Photo shows the overall look, before gluing and planing finished join. A few gaps which I'll try to fix using slivers (Full size).