Design for 3D-Printing

Here is what I have gathered so far, in case it helps anyone: 1) print ABS enclosed in a chamber temp of a minimum 50C, ideal 60-80C. 2) use quality filament, Polymaker filament is good; issues are plastic composition and diameter variation. 3) dry the filament properly. 4) the fumes will destroy your lungs and eventually the printers themselves, so they need to be vented out, and also filtered inside the enclosure. 5) bed flatness is critical. 6) use a good bed adhesive such as Magigoo.

Dissolve a portion of ABS in pure acetone (often available as nail polish remover). You're looking for something very roughly the consistency of milk. Colloquially this is called 'ABS juice'. Apply a thin coat to your bed/buildplate in the print area. I use a small amber glass bottle with a brush, but there are certainly faster ways to do this if you're doing a lot of printing every day. You now have a thin layer of ABS strongly attached to the surface of your bed. When you print ABS on top of this, it will be strongly attached to this, just the same as the layers adhere to each other.

You should be aware that acetone will damage PEI. It won't instantly destroy them, but it's something to be aware of. As a hobbyist, I just dedicated one side of my buildplate to ABS and don't care about the damage. You could just as easily use a different bed/buildplate material, though, since you're adhering the prints with ABS juice. I have had success with Kapton sheets in the past.

For hot-end temperatures, this is something you actually are best off figuring out yourself. To some degree, it depends on what you're doing and also your setup. Filaments generally come with a documented temperature range, but that should just be considered an initial starting point for testing. You should test print at different temperatures. The classic 'temperature tower' is a diagnostic print used for this purpose. Colder prints (to a point) will have crisper details and superior bridging. Hotter prints are stronger. ABS particularly loves to be printed hot, and when printed really hot I have found that layer failure pretty much stops occurring. ABS also abhors cooling. When testing cooling %s with a temperature tower, I found that even a small amount of cooling massively reduced layer adhesion. This does mean that if you're printing ABS for strength, you'll need to seriously limit overhangs and bridging at the design and slicing stage. Also consider that your nozzle can have an effect. It's often suggested to bump your print temperatures if you use a hardened steel nozzle.

Plastic composition is definitely something to be concerned about. Polymaker is solid. My favorite brand for ABS is Atomic Filament but they're too pricy to use in large quantities, so I save it for specific projects. For just one example of how things can get off with some brands, if you acetone vapor polish Hatchbox ABS it gets a matte texture instead of shiny, likely indicating there's something in there besides ABS.

Bed flatness is critical, but it's not something you should have to worry about. Good machines should have a decently flat and rigid bed to begin with, and even remotely modern machines also have mesh bed leveling features that correct for bed errors in software. It's usually not an issue nowadays. Back in the day, people would compensate by printing on a raft.

I didn't see you mention nozzles. If you're printing in ABS it's unlikely to be a pressing issue, but do consider that nozzles are a wear component and some filaments are abrasive. You will eventually need to replace your nozzles, as a worn nozzle can badly harm print quality.

Yep, plastic composition is a big concern and it is pretty annoying how the major manufacturers don't tell you exactly what's in their plastics. I suspect part of the problem is that many of them buy cheap material in bulk and they often don't know the finer details themselves.

Thanks for mentioning the nozzle wear, I should track that for sure.