After multiple rounds of iterating improved tools and techniques, I seem to have finally nailed the large format system (at least up to 24X36, haven’t gone bigger yet… 24X72 is coming). I plan on mailing off the first clients prints in a few days. He has suggested that I sell further copies of these prints to whoever wants them; I will discuss this a bit more, and if all are amenable, I’ll make them available. Until then I don’t want to divulge much other than to say it’s a copy of a prop-blueprint with modifications, not an aerospace blueprint.
The new system relies on UV lamps rather than sunlight. This took some time to get right; 4 lamps turned into 8. But the exposure time has dropped from something like 5 to 7 minutes of Utah summer daylight to 1 minute fifty seconds of consistent ultraviolet bombardment, day or night, sun or cloud.