I bought my first roll of ABS by Hatchbox to print replacement parts for my Mini and have found it surprisingly easy to work with. The surprise is that it doesn’t exhibit ANY of the shortcomings of ABS which I have read about (odor, curling off the build plate, poor first layer adhesion). I also read some Amazon reviews from other people suspecting that it isn’t even ABS at all - one person even said that the silver Hatchbox ABS partially dissolved in D’limonene. That’s used to dissolve HIPS.
I’ve been printing with ColorFabb nGen (prints at 230C and a bed temp of 60C) for a couple months and absolutely love it for its ease of use and great results. I swear this so called ABS acts like it is nGen! I printed a Benchy using Lulzbot’s ABS profile (print 240C bed 110C) and the bow has tiny ripples in it all the way up to about 10-12mm, the rest is really nice and smooth. The bridging in the wheel house is awesome, I can read the text on the bottom, I can almost read the text on the back. It was somewhat difficult to remove from the bed - just like nGen…
To diagnose the ripples in the Benchy I printed a hollow cylinder temperature tower using edited gcode (70mm tall, 280 layers, spiraled outer layer and no top, no infill, started at 240C and dropped the temperature by 5C every 40 layers or roughly 10mm). I watched it print the whole thing. Just like the Benchy, there were ripples until about 10-15mm. At around 20mm, the temperature dropped to 230C and the surface was really smooth. It started doing tiny pauses at the same place in every revolution around the cylinder at around 215C, nothing major, but noticeable. Not sure what caused it. Other than the little blemishes where the hiccups occurred, the surface was perfectly smooth from 20mm to the top.
I removed it from the bed and pinched it quite hard thinking the layers would delaminate near the top where the temp was set to 210C. It flexed a little bit but was just as solid as the rest of it. This is where nGen would have probably cracked, it tends to be quite brittle unless you crank up the infill percentage to at least 40%. Perhaps because I have left the extrusion rate at 100%, it is actually over extruding a bit and is contributing to this strength? I don’t know, I haven’t tested that yet.
I have come to the preliminary conclusion that the ideal print temperature is 230C (just like nGen!) and the rippling I saw was actually due to the bed temperature being too hot. I have yet to test different bed temperatures and will update when I find what stops the ripples.
Update: I have reduced the bed temperature to 85C and have seen some improvements, but still not gone. I reset everything by reloading the profile and only removing the top layer so my test piece remains an open top cylinder. No ripples! But now I have a seam down one side… I enabled spiralize outer layer and it was the rippling culprit!
Does anyone else have any experience, similar or otherwise, with Hatchbox ABS on a Mini? On a Taz?