Haha, the 1mm layer height was purely to see if the jamming was occurring due to the nozzle being pushed into the material. Not desired other than just out of interest.
So, I went back to the material that came with the printer, the mid range tension on the extruder, and re applied the default settings in cura.
I was able to print a draft quality and normal quality testcube. Both turned out great. I was impressed with the "normal" quality. It's not a normal quality in my opinion at all. Compared to other prints, I'd call it superfine quality haha.
I'm running a 6.5hr print right now, and about an hour in. Assuming it is done when I get back into work tomorrow I'll call this good.
After failing a print again with the gold material, I pulled the filament back to swap back to the silver material, I noticed that right at the head there was one of those "chew" marks in it.
Before I got my hands on the printer, someone else here was playing with it. I suspect what happened may have been that an initial jam was caused by something, possibly the Z height being a little off, possibly a tangled spool, who knows. I did notice that the thin sample spool that came with the UM3 was thin enough to slide around on the holder and the filament could get off the side and tangle.
After the initial jam, we might have pulled the filament out at the nozzle, trimmed up the end a little, then put it back in. Or perhaps failed attempts to correctly load fresh filament added a new chew point. Anyway, the chewed out section of filament was at this point somewhere between the extruder and the nozzle.
Printer prints fine for a while. Then, once the chew section gets to the inlet to the heater cartridge, it jams up due to the weird shape.
This happens a few times in a row while I start fiddling with other settings, trying to get things to work. Tension, layer height, different filaments, etc
I guess I'll just have to be careful, and after a new filament load, inspect the filament as it travels through the bowden to ensure it looks free from marks.
Anyhow, that's my figuring for now. Looks good anyway, still got to try PVA support and high quality.
Thanks for suggestions. I'll keep you posted if I run into more problems!