I’ve let this base dry for three years in my attic. It is approximately 2-3” thick. I had both sides painted with a latex paint. About 1 month ago I machined and flattened one first side. Now at this time the top is in my shop (heated). Two weeks later I placed my table top back on my jig to flatten the other side. At this point no cupping had happened. I flattened the opposite side. I went to finish up the machining on the second side last weekend and now it is cupped. The center is higher then the sides. I’ve placed it back in the attic to see if the moisture content will help get it back to where it was. Is there anything I can do to stop the movement? I would hate to re-machine both side just to have this happen again. Any ideas would be greatly appreciated.

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The reason for the warp is moisture content difference from one side to the other. Get it uniform before machining and also make sure you remove equal amounts from both faces and use the same finish on both faces to keep the MC balanced.

Or you could save the effort and just burn it now.

Howdy alljays, just curious what kind of wood you got there.

With both sides painted with latex paint, you may not have an adequately dry piece, especially if there is not good air circulation around it. I would check the moisture content with a meter. Put it in a place where it has good air circulation around both sides for a month and see what happens. Don't give up on it. The fact that it doesn't have radial cracks is cause for hope. Looks like a very nice piece.

Jamie, Its a red oak.

I take that back. Looks like it might be a white oak. Here's a picture of my kid working on it.

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Looks like it's an Elm or a Black Oak to me.

Put it in a place where it has good air circulation around both sides for a month and see what happens.