Here is a top leveler design from the guys at offroadfab site that looks interesting if you need to have a very flat surface over time.
"The 1/2" plate top had five pieces of 1/2" x 1 3/4" bar stock welded to the underside of it, perpendicular to its length. So because of this the plate had a substantial bow to it. I needed to have a way to pull the middle of the plate back down (flat) so I welded three all-thread studs to each of the stringers making for a total of 15 studs. The studs are welded on the stringers at 16" centers giving me a left a right and a middle. On the frame that I built for the table I made five crossmembers with three tabs each to correspond with the all-thread, the all-thread studs pass through the tabs with a nut top and bottom each tab. Having a nut top and bottom lets me either pull the plate down (with the bottom nut) or jack the plate up (with the top nut). The plate only rests on the frame at the four corners (the 2 x 4 tube is welded 1/4" down from the top of the corner legs) so that if there was any bow in the frame upwards (which there wasn't) I would be able to still pull the plate to flat. Then it was just a matter of pulling or jacking with the nuts on the all-thread studs and the use of a straight edge to get the plate flat. It seemed to work well and if I did it again I would do it the same way."
Jim
|