It’s 30" above the workspace, 12’ topbeam. Went with pressure treated with the idea that it wouldn’t bent warp as much since I couldn’t find a 12’ unistrut. Sled is 26.5 pounds. Have to extend my side skirts down a bit and put a small skirt on the top. I have an idea for an adjustable top beam that rides on t-tracks, but don’t yet know if it’s really necessary. Performed Holey Calibration 4 times and got it down to a 2.042 mm error. Can you get much better than that?
I ordered 1x 10’ chain with 2 master links from Amazon and split it in half. I added the full 5’ to each existing chain which was too much. When the sled was top left or top right the excess chain being taken up by the pulleys maxed out. I then cut some more off and reattached, I think I’m still going to take a bit more off. I’ll edit with the exact length that I added.