I really love the Ultimaker 2+ but unfortunately it is out of my budget as a second printer. I forgot to mention I already own a Zortrax M200 but want to print with other materials such as Ninjaflex, Woodfill, Bronzefill, Carbon fiber etc.
i don’t have any experience with ABS. It’s smell too much. Normally i use nGen, XT, bronzefill, woodfill or PLA/PHA from colorfabb, my two printers have a heated bed.
The buildtak manufacturer claims that its buildtak surface works with ABS, but when it’s pôssible he prefer a heated bed.
You can give it a try without and decides afterwords if a heated bed is needed. The purchase of a UM2go and the upgrade with a heated bed will cost a little bit less then a purchase of an UM2+. So at the end i’ll choose for the UM2+
What country are you in? 3dsolex sells a um2go HB kit in most of the world, thegr5store.com 1 (my store) sells it in USA. These places also all sell a 1.75mm conversion kit if you want to continue to use your 1.75mm filament.
Ultimaker specifically will tell you that you can’t print ABS without a heated bed. For good reason. I printed some ABS parts on my um2go last night and even though they were tiny (4 minute prints) I had to enclose the printer completely to get good results.
I recommend staying away from ABS. There are much better materials out there (easier to print, stronger, higher glass temp, less brittle, etc). Why do you want to print ABS and not PLA?
It’s all about power management. The power supply that comes with the um2go can’t run the servos, the nozzle heater, and the HB all at the same time. So instead of spending another $100 for a power supply I wrote code that never turns the nozzle and HB on at the same time with nozzle getting priority. But when printing ABS at 240C that meant the nozzle was on so much that the HB wasn’t getting it’s chance and I could barely keep the bed at 60C (fine for PLA). Increasing the wattage of the nozzle means the nozzle is off more of the time and so the HB can stay hot enough to print ABS (over 100C).
You could alternatively get a UM2 style power supply (around $90-$150) and leave the 25W heater in the um2go but I don’t know of any firmware for um2go with heated bed that doesn’t also include my power sharing algorithm so you’d have to make your own firmware. I try to ship 39W minimum with um2go kit.
So from my layman point of view let me explain again for my own understanding (correct me if wrong):
The original 25W heater “hogs” the power supply because it can’t draw that much current per second (or it is not designed to do so).
Whereas the >39W nozzle heater can draw more current per second, heating itself up quicker and giving the heated bed more time to draw current from the power supply.
And in the end it’s cheaper to upgrade the nozzle heater than the power supply system.
Thank you for your contribution for this. I am one of the few who needs it and luckily someone on the internet has come up with a solution! Cheers
Another way to think of it is this - I couldn’t come up with a safer solution in software to share the power. In theory I could let both heaters be on at the same time if I’m very very careful with overall power usage over the course of a second. But this software solution would be more complicated, harder to 100% test, and more likely to have a bug that cuts power half way through a long print! Plus I wouldn’t be 100% sure it would work with all um2go power supplies.
But the solution I came up with is easy to test (tested actual power usage by cutting open the power cable and inserting current measurement using oscilloscope).
the heated bed kit will be here on Saturday. Getting some stuff prepared for the installation. I have a question about the Tinkergnome Firmware perhaps you could help me. How do I load the firmware? Thanks for your help!
After downloading, connect USB between your computer and printer and using CURA choose “install custom firmware…” and select the downloaded hex file. It’s easy to go back to original firmware also in CURA.
Maybe time for an upgrade as mentioned by DIM3NSIONS 
