Since I routinely cut 19mm (3/4") plywood, there is precious little clearance between the bit and the work surface. So little, in fact, that I can't use my great little OB probe. So over the weekend, I replaced the standard Y-axis plates with 2" higher plates. What a difference. This involved removing the X-axis stepper and the two Y-axis end plates, threading out the Y-axis acme screws, then the removing the X-axis C-beam. Quite a mission for a one-man operation. Replacing the gantry plates turned out to be both easy and a pain in the proverbial. I ended up having to do it THREE TIMES. Mainly because I kept putting the plates on the wrong way round. The logo goes on the inside, and the cable cut-away faces to the rear. This puts the bearing recess on the inside. Sheesh! Re-threading the acme screws turned out to be far simpler than I expected. They just went in, without complaining. But the single biggest lesson I learned was that bolts either work themselves loose, or I hadn't tightened them adequately in the first place. Many bolts were dangerously loose and had to be re-torqued. Checked and double checked. I have wooden stops on all four corners screwed to the wooden bed on which the Workbee sits, which assures me that the Workbee is perfectly square. After manhandling the aluminum frame (to get underneath the frame in order to replace the spoilboard also), I manouvred the frame back into position snugly enframed by the wooden stops, I measured the squareness of the frame by the diagonal measuring method, and the frame is well within 1mm square. Actually, the difference was too small to accurately measure, Then I tightened up all bolts. So - new Y-gantry plates, new spoilboard, re-crimped stepper motor cables and everything torqued up tightly. Today I'm levelling the spoilboard. Regards, Duncan
