Sunday, July 17, 2011

Now with Real Tilting Action!

I've been working on the resin tray. I needed a way to be able to test different coatings/coverings for the glass at the bottom of the tray. To that end I have made a frame that will hold the glass. I can prepare glass pieces with different coatings and change them easily. I do feel that I cheated a bit as I used my CNC to make the frame. I probably could have made it with my table saw and router table but the CNC was faster and much neater.

The tray will slide into a holder that floats on springs. It can be leveled by adjusting the bolts at the corners. The holders were made with much more mundane tools. A hacksaw for the aluminum and a table saw to cut the HDPE blocks. A drill press was used for the holes. What you don't see is the threaded inserts I found at the hardware store. They screw into the MDF and the bolts are threaded into them. The blocks slide up and down nicely on the bolts (I found some that had the top 2/3 unthreaded) but I found that I needed to open up the holes on the underside of the blocks so the bolts could "wiggle" a bit . Otherwise they would bind up when only one side was pressed down.


Here you see the finished assembly with a stepper motor to provide the tilting action. There is a eccentric (off center) wheel that presses down on a lip on the back side of the tray. The tray will be tipped between layer exposures to help separate the cured resin from the vat floor. Then the Z axis gets raised slightly before the next slice is exposed. I may need to relocate the stepper so it won't interfere with the Z axis.