I don’t have access to a 24” planer or drum sander, so I figured I was on my own. Much googling later, I found the Tage Frid method for levelling a benchtop in situ with a router.
I grabbed me some cheap, but cleanly joined poplar, built out my custom rails and router sled, bought a big honking flat router bit, and set up to flatten!
I took a very thin pass across the top, just barely touching the top of the cup in the bench. This operations throws up a HUGE amount of dust into the air and spews shavings all over. I had the JDS cranking out at max, and I still had to leave the shop for a bit after the first pass to settle.
You can see where the bit just kissed the top in the center of the table, under the shavings-free part.
That was enough for today. My proof of concept was done.
Now I just need to don the mask, shield, and crank up the filter, and make a few more passes.
I will probably borrow a big air-mover fan from the office, just for this operation.