Welcome to the SeeMeCNC Community

Out of all the printers I have owned this one has become my nemesis- from calibration issues to clogged hot end, I would just like it to work. Latest problem, I turned on the printer and brought the hot end up to 180C so I could remove the .4mm stainless steel nozzle and the printer just died. The only thing working is the power supply. I have check the power outputs of the power supply, the two axillary fans are working, there is power into the Rambo board, the fuse on the Rambo is intact. There is no LCD, no lights on the Rambo- there are no indications of a short anywhere, no sounds, smells and so on. I have no idea what could have happened. If anyone has ideas of what I can check I would be humbly appreciative. I have the next 4 days off and was planning to do some printing.

Thank you- Tim

There's more than one RAMBo fuse.

First rule of 3D printing - don't touch it with a metal tool if it's turned on. AT ALL.

g.

geneb wrote:There's more than one RAMBo fuse.

First rule of 3D printing - don't touch it with a metal tool if it's turned on. AT ALL.

g.

It is a tricky thing, the print head had to be heated up to remove the nozzle and I was worried if I shut it off the thermal fuse might pop however in the future I will just have to work as quickly as possible. Back up and running now, the new dev branch of the firmware seems to be calibrating well. Any idea when they will finalize the firmware and if there a possibility of a calibration code being created to probe more points on the bed?

Thank you Gene!!

What I do is heat it up, power it off and then quickly loosen the nozzle. Power it back on (to restart the fan) and remove the nozzle by hand using a thick washcloth as an insulator so I can grab the nozzle with my fingers.

g.

So how did you fix it? I'm having the same issue - no LCD, no lights on the board and I checked all the fuses and they seem fine - no burn marks and no smells. The PSU is working and the fans connected to it but outside of that nothing else is working

SonnyDR wrote:So how did you fix it? I'm having the same issue - no LCD, no lights on the board and I checked all the fuses and they seem fine - no burn marks and no smells. The PSU is working and the fans connected to it but outside of that nothing else is working

Did you pull the fuses and checked them for continuity?

Thought there was only the big fuse (15) but actually it was one of the small ones that was fried. I replaced and everything is back to normal.

I had a very similar issue here. I figured out the cause, but thought it might be worth posting in case anyone else is having similar issues.

So my F3 fuse (according to this picture) kept popping. It started after a fail print mess. I tried to raise the temp of the nozzle to something like 200, to melt the now-solidified PLA, and immediately lost power to everything aside from the PSU. I checked with a multi-meter, found F3 to be the bad fuse, and replaced it (after waiting on shipping). The unit turned on again, and worked up until I tried to raise the nozzle temperature, which popped the new fuse.

At this point, I had a pretty good indication that the hot end was the source problem, but none of my connector wiring looked suspect (at least, nor more than usual). Still, I disconnected the platform, cut the filament, and pulled the top cover off. Wiring there looked fine, too, but as I examined the heating element, I found this.
The picture was taken after I had separated the wires a bit. Far as I can tell, when previously trying to wrench the nozzle off, I must have twisted the whole hot-end enough to pinch and move these wires. Once they were separated (and a new fuse added, boy am I glad I ordered several), and the printer heats up properly. Now if only I can figure out how to remove a PLA jam from inside the hot end.

zxaber wrote:I had a very similar issue here. I figured out the cause, but thought it might be worth posting in case anyone else is having similar issues.

So my F3 fuse (according to this picture) kept popping. It started after a fail print mess. I tried to raise the temp of the nozzle to something like 200, to melt the now-solidified PLA, and immediately lost power to everything aside from the PSU. I checked with a multi-meter, found F3 to be the bad fuse, and replaced it (after waiting on shipping). The unit turned on again, and worked up until I tried to raise the nozzle temperature, which popped the new fuse.

At this point, I had a pretty good indication that the hot end was the source problem, but none of my connector wiring looked suspect (at least, nor more than usual). Still, I disconnected the platform, cut the filament, and pulled the top cover off. Wiring there looked fine, too, but as I examined the heating element, I found this.

Spoiler:

pla-plated.png
Yes, this is my first major wiring project. Why do you ask?

The picture was taken after I had separated the wires a bit. Far as I can tell, when previously trying to wrench the nozzle off, I must have twisted the whole hot-end enough to pinch and move these wires. Once they were separated (and a new fuse added, boy am I glad I ordered several), and the printer heats up properly. Now if only I can figure out how to remove a PLA jam from inside the hot end.

I suggest heating it up to at least printing temperatures, removing the nozzle (If it went back on or hasn't come off yet), then removing the heatbreak+heater block from the heatsink. Then warm it up again, and take the back end of a drill bit and push downwards. If there's more in the hotend beyond the heat break, push the filament down through the heatsink with these parts removed. If it won't move on it's own, push the bowden tube through as well.