Steve Wurster
04-11-2010, 9:53 AM
Hello,
I'm running a bunch of cherry through my Jet 8" J/P combo machine, and am noticing a problem. After I run a board through the planer with the flat jointed side down, that same side will come out cupped after the rough side is planed smooth. The cupping is actually convex, meaning the board is higher in the middle / thinner at the edges.
I check the jointed side before planing and verify that it is flat across both the length and the width. I then use the planer to smooth out the rough side, but only until it's smooth and not yet the final thickness. Checking the freshly planed side, I find it flat across length and width. Flipping the board over and checking the jointed side, I find it flat across the length but now convex across the width. The board actually seems to be thinner just on one side, and flat across most of the width.
What the heck is causing this? Is this just the forces in the wood releasing, or could it be the planer table is not flat across its width and actually bending the wood? At this moment, I'm ruling out the knives not being parallel to the table, only because this is the jointed side that is getting cupped and not the planed side.
Any ideas here?
Thanks,
Steve
I'm running a bunch of cherry through my Jet 8" J/P combo machine, and am noticing a problem. After I run a board through the planer with the flat jointed side down, that same side will come out cupped after the rough side is planed smooth. The cupping is actually convex, meaning the board is higher in the middle / thinner at the edges.
I check the jointed side before planing and verify that it is flat across both the length and the width. I then use the planer to smooth out the rough side, but only until it's smooth and not yet the final thickness. Checking the freshly planed side, I find it flat across length and width. Flipping the board over and checking the jointed side, I find it flat across the length but now convex across the width. The board actually seems to be thinner just on one side, and flat across most of the width.
What the heck is causing this? Is this just the forces in the wood releasing, or could it be the planer table is not flat across its width and actually bending the wood? At this moment, I'm ruling out the knives not being parallel to the table, only because this is the jointed side that is getting cupped and not the planed side.
Any ideas here?
Thanks,
Steve