I got very very lost while looking for the edge of the map, so I started trying to find my factory haha. I thought I would eventually hit a wall and could then search in a pattern. I started leaving a trail of every machine I could afford like bread crumbs to help keep my bearings.
Turns out, I could have refreshed the whole time! Then I tried in vain for ~40 minutes to find my subdimensional market without editing my save, and I couldn't get a second one without accessing the first. I built trails of machines in spokes around my factory, but I didn't get beyond roughly Y=10,000 before giving up. I ended up taking a few zeroes off the coordinates and found it pretty easily. Totally my fault, but it was almost impossible to recover from that mistake without editing my save or resetting.