Featuring extensive t-nutted and tab-and-slot connections, I quickly became thankful for ordering a small file set to get into the tight spots on the waterjetted assembly. Unsure of the offset or tolerance settings on the cutter, I just had to make a guess on my dimensions. Some turned out tight, others were spot on. With that, the pieces slowly started coming together:
With the easy parts done, the laborious process of drilling out all the holes in the vertical angle aluminum began. It took several night sessions on the vertical mill to get all of them, but the results were worth it. I opted to not try and waterjet vertical members and t-nut along the edge, because of worries about accuracy. It was at this point that I also started adding the acrylic panels (laser cut near the end of summer). Everything is 1/4-20 tapped for maximum convenience:
Unfortunately I don't have any good pictures of more recent progress. All of the aluminum members are installed, and the last few acrylic pieces will be ready once I manually drill a couple more sections. The biggest question mark in this project has been the z-axis gantry. After press fitting the bronze bushings into their aluminum mounts, I temporarily installed the guide shafts and tested alignment. The flexure mounts on the carriage were certainly pulling their weight, but I still found a lot of resistance when I attempted to run it up and down. Reaming the insides of the bushings helped significantly, but I'm still not happy with the results yet. I have multiple theories as to the cause of this, but the number one is the accuracy of the t-nutted connections. I installed and tightened the pieces together before installation on the rails, and noticed some definite play in the position of the plates. I plan on loosening and and refiling the carriage pieces before re-tightening them on the rails to see if this solves the problem. The other potential issue I see could be bushing alignment. The press fits for the bushings was looser than I would have liked, and I suspect this allows them to twist out of colinear alignment.
While I could just switch to the linear bearings I use elsewhere on the machine, I feel that the bushings are a more robust choice when supporting such a large cantilevered load (and desiring to minimize vibrations and wobble). Next up on the printer project is more machining, 3d printing of the x/y gantry pieces, and wiring of the electronics!
