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denver
06-08-2008, 10:56 PM
I want to make some pallets using quarter sheets (2'x4') of 3/4" MDF. I'm going to cut four grooves evenly spaced across the short dimension for t-track (3/4" wide, 3/8" deep). I'm also planning a sequence of narrow, shallow cuts 1" apart along the long dimension. I'll do those with a 14 degree V bit. All the grooves are on the same side. The narrow ones are just reference lines for alignment, so they're optional.

All those grooves will make the panel cup in both directions. In fact, I already made one just to see, and all the edges did lift. Not a lot, but enough so it doesn't lay quite flat, even with the vacuum. So I need to make compensating cuts on the other side. However, since I'll be using vacuum to hold this thing down, the relief cuts will need to stop short of the edges. And at least the ones compensating for the t-track grooves can't be directly opposite or I'll end up with five pieces of MDF.

Are there any rules of thumb for figuring out sizes and placements for relief cuts in a case like this? And if I make them on the already cupped piece will it straighten out?

Thanks,

Denver

Gary Campbell
06-08-2008, 11:10 PM
Denver...
Try making your cuts just thru the first layer of veneer. The next layer in will be at a skew angle to the face. Place them between the cuts on the other side. You may not need as many to relieve pressure as you have for reference. Let us know how it turns out.
Gary