I stuck my indicator back in the collet and took 15 readings relative to 0,0 in a 3x5 grid.
What I see is a slight bump in the middle of the wasteboard running from front to back or Y direction. Worst case along the Y axis is 0.73mm over 800mm and that’s in the center of the board from x610, y0 to x610, y800. The others taper off from this ridge toward X0 and X1210. But generally I see the back (Y800) is slightly higher (about .51mm) than the front (Y0).
Left to right along X it is almost dead flat measuring at Y0, Y400, and Y800. Worst case is .22mm difference over 1210mm (0.009" over 48").
I might look at loosening the mounting bolts for the QCW rails along the back side and see if they will drop down just a smidge. Maybe just loosen and retighten and see if that helps. I don’t see it getting worse. If I can flatten it out a bit more before I take the surfacing bit to it that would be good.
I am very interested in this concept- that fourth axis option is one of my goals in the very near future. Using a drop-section to facilitate larger radius pieces would be genius. If you accomplish this with any decent results- I would love to open a dialogue with you on the successes and pitfalls of what you are attempting.
I was considering doing a similar hole option but with a router table drop in piece that could be replaced but at the same time be able to be waste-board-trued up and not have the flex that a hinge would involve… dcconline@sbcglobal.net
I got the Jet and at first was very happy. but as I cut more on the CNC what I realized was that there are often chips that get stuck in the spiral portion that then block other pieces from getting through. I am forever having to clean out the spiral. Would not buy if I had to do it over.