Almost two years ago, I purchased a PrintrBot Simple Metal kit for my family with the heated bed option. For 3D printers, this kit provided an inexpensive way to get into 3D printing. It shipped with the original Ubis ceramic hot end. For smaller prints this hot end worked fine. Each time I would try a more ambitious print, I would get a failure. At one point, the hot end completely jammed up and I wasn’t sure if I could even get it to print again.
I was able to get it going again, but never reliably. It seems that whenever I printed something that took over 2 hours to print, it would fail somewhere in the process. I became very frustrated as this limited me to small objects if I could get it to print at all.
After a bit of thought, I came to the conclusion that at least on a few occasions, the long print time was allowing the heat to travel up the hot end to the cool zone and melting the plastic where it shouldn’t melt, causing the jam. After a few times of this happening, there was probably plastic residue left behind causing jams to be more frequent. I felt like the heat moving up the hot end was a design flaw, so the only real fix to my problem was a new hot end.
The Ubis 13S was designed to combat my problem. The cool zone of the hot end is metal with fins to allow lots of cooling on long print times. There’s still a small ceramic piece just above the tip which I imagine keeps the temperature more stable. This hot end is designed with the same dimensions as the original hot end, so it’s a direct replacement.
To install this hot end, I just unplugged the two connectors from the original, pull out the old and put in the new. PrintrBot strongly recommends running a fan across the fins at all times for maximum performance. I haven’t printed the adapter for my fan yet, but using a small desk fan keeps things cool for prints lasting 3 hours or less.
I did reflash my motherboard with the latest firmware. I’m not sure how much this helped my print success, but I figured it couldn’t hurt. I hadn’t upgraded the firmware since I purchased the machine so it was time.
After installing the Ubis 13S, you should go through the Z calibration process again. Even being super careful with the installation, the exact Z position of the tip probably has changed and it’s good practice to double check all your settings before jamming the hot end into your build plate.
I’ve printed three objects so far with the Ubis 13S hot end and I can’t be happier. The first print was a bust of Yoda at 0.2mm layer height. It took just over 3 hours to complete. There are a lot of overhangs with the chin and ears which was a good test of the support structures. I use Simplify3D to slice my models. The supports came over really each and the print quality is great. The old, ceramic hot end didn’t leave a good finish on the last layer. That issue is gone with the new hot end.
The next two pieces were the same model, the Maker Faire Robot action figure. With two nephews, I needed two robots, and this would be a good test to see if I got repeatable performance out of the new setup. Both robots came out looking really good with all supports coming away easy. This object has built in sockets and hinges to give movement to the arms, legs, and head. With a little coaxing I was able to break all joints free. This means the layers didn’t melt into other layers or over-extrude, otherwise the joints would be frozen.
So far, I haven’t printed with anything besides PLA from PrintrBot. This hot end is rated to reach temperatures of 270 deg. celsius, so it should make printing ABS easier. The more fans to encourage rapid cooling definitely helps with details and finish.
I feel like I have a new printer. I love the simple design of the PrintrBot Metal, but I never felt super comfortable with the ceramic hot end. I read posts of other PrintrBot owners that had already moved on to different metal hot ends to get better performance. Now I have the official metal hot end and the performance I expected from this 3D printer. Thank you PrintrBot and Ubis!