what's the longest you should run a print?

[gencode]

100% infill ? What are you trying to print ? :-)

I had jobs running for 40 hours and more (on a 55x55x55 cm printer) ...
Never ever used 100% infill ! (30% seems more then enough for most of my "strong" prints)

good luck,
Kris

Great, its just a machine part replacement that I may need to sand or cut some off to make it fit afterwords. so def needs to be solid, I can't get my calipers where its at to get exact measurements.

Well it sounds like 19 hrs is not that long then for these things, cool!