WARNING! Do not print ABS if you just received your MK3  

Re: WARNING! Do not print ABS if you just received your MK3

I got no problems over here with ABS at 80°C / 255°C on my mk3.
What is your heatbed and nozzle termperature?

Re: WARNING! Do not print ABS if you just received your MK3

The standard generic ABS setting in Slicer PE so I think 255 /100.

It's pretty strange that both new printers lasted exactly 3min while I had no problems with a printer from another batch. When did you get yours?

Re: WARNING! Do not print ABS if you just received your MK3

Is your printer built for 230V 50 Hz or do you have a different voltage and frequency?

Re: WARNING! Do not print ABS if you just received your MK3

I've no plans to print ABS, but PETG, PC, Nylon...

Re: WARNING! Do not print ABS if you just received your MK3

I printed ABS perfectly fine with the exception of the print sticking too well to the bed and it tearing the PEI off when I tried to remove it. Printed at 255 / 100.

Perhaps this could be an environment issue?

Your best option is to contact Prusa support.

Re: WARNING! Do not print ABS if you just received your MK3

Actually PRINT ABS ONLY NOW! As long you are under warranty, do any load test for your printer. Bad PSU's will be replaced

Re: WARNING! Do not print ABS if you just received your MK3

I received my MK3 back in February and remember the big thread on this issue. There were a small percentage that were having problems. I was all ready to have this problem. I purchased a Meanwell ps as a spare and have been printing connected to a strong UPS with no problems.

Tonight I will finish building my second MK3 so I'll look out for this, so thanks for the reminder. Once I get both printers printing well I'll take one off of the UPS and see if it stays up.
While under warranty you get free replacements. If you keep having problems search for meanwell power supplies that others have used. There's a mount for them listed so I would print one just to have it on hand.

Re: WARNING! Do not print ABS if you just received your MK3

Actually PRINT ABS ONLY NOW! As long you are under warranty, do any load test for your printer. Bad PSU's will be replaced

Haha. Yeah. Correctly it would have been:

WARNING! IF YOU HAVE A NEW BATCH OF PRINTERS DON'T PRINT ABS BECAUSE IT'LL MAYBE POSSIBLY RISK BREAKING YOUR PSU UNLESS YOU HAVE TIME FOR DOWNTIME AND/OR A SPARE PSU THAN GO AHEAD AND PRINT ANY ABS PRINT TO TEST IF YOU HAVE AN ABS DOA PSU.

But that just didn't roll of the tongue as well:D

Tonight I will finish building my second MK3 so I'll look out for this, so thanks for the reminder. Once I get both printers printing well I'll take one off of the UPS and see if it stays up.
While under warranty you get free replacements. If you keep having problems search for meanwell power supplies that others have used. There's a mount for them listed so I would print one just to have it on hand.

Already ordered two Meanwell PSUs yesterday, just after the PSUs broke. But thanks for the tip. I am just extremely bummed that this is an issue especially since the downtime could not come at a worse timing.

Re: WARNING! Do not print ABS if you just received your MK3

...I am just extremely bummed that this is an issue

It's still a mystery why it's happening only for some people. My assumption is
1. less stable power grid in USA (in LA area I measured 105V - 140V). That's horrible for a power supply. Especially if it's going towards 100V, the current flow is pretty high.
2. Power supply is working under max ratings for some components in some situations. Under certain conditions there are spikes which can't be handled because there is no buffer. This is pretty hard to reproduce. Can you post the gcode which killed your two printers? Let's see if we have finally found a "gcode of MK3 death"! 😉

... especially since the downtime could not come at a worse timing.

Let's call it Murphy's law 😉

Re: WARNING! Do not print ABS if you just received your MK3

...I am just extremely bummed that this is an issue

It's still a mystery why it's happening only for some people. My assumption is
1. less stable power grid in USA (in LA area I measured 105V - 140V). That's horrible for a power supply. Especially if it's going towards 100V, the current flow is pretty high.
2. Power supply is working under max ratings for some components in some situations. Under certain conditions there are spikes which can't be handled because there is no buffer. This is pretty hard to reproduce. Can you post the gcode which killed your two printers? Let's see if we have finally found a "gcode of MK3 death"! 😉

You might be on to something. I am not living in the US but in Japan. While the power grid is extremely stable, the voltage is a nice, stable 100V...

I am posting the link for the gcode of death here. Its an ABS case made with rim and raft since precise holes were needed and the plate heat always messes with the hole measures. You can stop the print when the printer starts building the actual model (after rim and raft).
DO NOT USE THIS FILE IF YOU ARE NOT WILLING TO BREAK THE POWER SUPPLY OF THE MK3 (god i love caps)
https://1drv.ms/u/s!AjwietZirFfNhKhIsayswBO-0b6uhA

Re: WARNING! Do not print ABS if you just received your MK3

For those in the US if you are worried or have had issues with power supplies try adding a good UPS. I just finished calibrating my second MK3 and everything went well.
For the last two days I've been printing the new R3 parts for the extruder. My new build has those on and I'll rebuild my first one next. For the extruder parts I was printing with ABS with no issues on the UPS.
The model I have is the APC BR1300G Back-UPS. I purchased the power supply below as a standby. I need to print the bracket for it.

Mean Well NES-350-24 24V 350 Watt UL Switching Power Supply 120 Volt

Re: WARNING! Do not print ABS if you just received your MK3

One suggestion:
Put whatever fan you can find laid around to blow to stock PSU. More airflow better.

My PSU (running at 100V environment) is extremely hot while doing PETG 240'c/90'c, I mean untouchable hot. Put whatever fan you can find, one or two or whatever, to keep it cool!

At the end I still go over to MW NES-350-24.

Re: WARNING! Do not print ABS if you just received your MK3

My version of MK3 PSU cooling fans:
https://www.thingiverse.com/thing:2885275
No problems so far and yes, it has also has kept velociraptors away.

Re: WARNING! Do not print ABS if you just received your MK3

One suggestion:
Put whatever fan you can find laid around to blow to stock PSU. More airflow better.

My PSU (running at 100V environment) is extremely hot while doing PETG 240'c/90'c, I mean untouchable hot. Put whatever fan you can find, one or two or whatever, to keep it cool!

At the end I still go over to MW NES-350-24.

Thanks for the tip. I will take some meassurements of the temperature and maybe send it to Prusa so they at least think about a 100V model of their printers.

BTW. Did anybody dare to print the gcode of DEATH!!! ?

Re: WARNING! Do not print ABS if you just received your MK3

BTW. Did anybody dare to print the gcode of DEATH!!! ?

Yes, printed on mine and still working fine 🙄