Router table top

[1oppo]

Hi

I bought a 3/4" sheet of MDF to make a router table top, my old table top is not flat. Today I cut the sheet into 3 pieces 32" x 48', when I checked them they are not flat. I had planned to laminate 2 pieces together so the would be 1 1/2" thick. I am using a Woodpecker PRL lift and a Miluakee 5625 router. I know I am going to have to support it to keep it flat. How do I get the MDF flat to start with? I noticed my original top was not flat when I tried my incra fence to cut som joints and could not get the depth of the cut the same all the way across the material.

Thanks
Ed

[JR]

If you have a flat surface available for assembly then the problem should go away when you glue the two pieces together. Just clamp the glue-up to the assy table and it should come out flat.

Alternatively, you could build a sub-frame for the table surface. Use square stock and screw the top to the sub-frame.

JR

[poolhound]

Agree with JR. I would build a subframe and make sure it is square and that there is support as close to the router plate as possible. Once its assembled everything should flatten out. You can the either laminate or treat the MDF with multiple coats of poly.

[LarryG]

Whether you elect to use a subframe or not, when you laminate the two layers of MDF orient them so that their crowns are facing each other (i.e., they touch out in the middle but not necessarily all the way around the edges). When you apply clamping pressure around the edges, they'll pull each other straight.