Norm Abram says to put the screws in the middle in like usual but to ream out the hole in the frames that the screw goes through in the front and back to allow for wood movement. What I'm wondering is, won't the head of the screw go into the reamed out hole and bind up? Is there a better way to put the top on to allow wood movement?
It looked like to me that Norm drove that screw in the front in tight. If he did that it would make the sections of the top captive if the center screw on the sides were tight.
The holes should be elongated, not just "reamed out". On the sides of the cabinet, the center screw can be tight on both sides. The ones front and back should have elongated holes. Along the front and back edges, the elongated holes should be perpendicular to the top.
Washer head or pan head screws with washers can be used. This procedure applies for a solid wood, or glued up sections of solid wood for the top. not for plywood tops.
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