Today I’ve finished fitting the tops to the workstation – they’re not screwed down yet as I just put a coat of Danish Oil on the exposed wood – probably not necessary but I like the way it looks. One minor snag I ran into when I started to fit the tops was that there is a sag in the middle of this thing – about 1/8” or so. I noticed the sag when the top left side didn’t sit level, the outer edge was above the level of the edge against the saw. I measured and remeasured the height from the cabinet top to the saw top and the height of the end panel plus the top thickness and they were the same. Finally thought to check the sag and there it was. I ran a quick beam calculation using Young’s Modulus for Douglas Fir and assuming a uniform load of 600 pounds and sure enough the calculated sag was just about 1/8”. When I reinstall the rip fence and screw the tops down tight and add the oak cleat across the back the sag should be reduced considerably so I didn’t want to lock it in. I jacked up one side of the workstation with the levelers and put a piece of 3/4” plywood between the base and the floor about in the middle of the span. Then I let the weight down onto the piece of plywood until the sag disappeared. I’ll screw the tops down and install the rip fence and the cleat before I remove that piece of plywood. Might even reinstall the piece of steel angle that the back of the rip fence used to ride on – it won’t reach any more. Here’s a picture showing the aluminum angle on the left side of the saw with the new top a few inches away. You can see the clearance holes drilled in the oak edge banding to clear the bolt heads.
And here’s one of the fitting process for the left top. The straightedge helped to get the aluminum angle positioned correctly. I arranged the tops so they are slightly below the level of the cast iron – 1/64” or so. This should prevent snagging of workpieces (I hope).
And here’s one with both tops in place, ready to be screwed down.