After two successfully printed but quite small object I started to work on something bigger. I faced the leveling problem of the Z axis again. It is aligned well on one side but not on the other.
After some fighting it finished this object. Anyhow I didn't liked the brown burned small spheres what appeared on the print. I presumed that these are some plastic from the previous prints.
On Tuesday evening I started to work on the next piece.
At the setup I realized something about the Z axis:
If I not hold tide the threaded rod on one side when I turn it on the other, they turning together and wryness will be left there. (It is weird a little bit, because the two sides has two independent stepper motors. Maybe an additional timing belt is there)
After this I started to print. It forecast the project to 9 hours. Even in the evening I seen, that there is some problem with the project, because the brown spheres are continuously generated.
The head leaks somewhere. And I seen the same in the morning but the print was not finished.
While I was waiting to a meeting with one of my clients I searched for the replacement part list (exchange the head). And I found even better thing:
http://diy3dprinting.blogspot.hu/2014/01/best-robo-3d-printer-fixes-tips-tricks.htmlFor not to much money I can upgrade the machine.
When I arrived to home, checked the print. The last few layer was missing and the layers were there were slipped away a little bit. The extruder was clogged. I tried to clean it in an easy way but the filament broke at half way. This means I should disassemble the whole extruder sometime during the night.
First of all, I ordered the new metal extruder.
After this I started to clean up the old one. Removed the head from the holder, but I still wasn't able to remove the filnament from it. I wanted to take it apart anyhow, to eliminate the leakage. This ony can be done when it is hot.
Switched on the heating and started to screw it with two pliers. I grabbed the metal part at a wrong spot. There was a little spark.
The head taken apart and cleaned.
I can't screw it together, I suspect the plastic should be heated for this to expand.
The head doesn't heat at all.
I found out what is in there (RAMPS 1.4 board), grabbed drawings for it. I was measuring around a little bit. It looks like I killed one of the MOSFETs (I think, that a 60V 55Amps rated FET should survive this and the fuse should blow, but it makes no difference).
The ST made FETs are in there according to the drawing was not available at the Lomex, so I bought some with similar parameters from IRF.
Yesterday evening finally removed the control board from the enclosure, removed the RAMPS board from the top of the Arduino and...
"a 60V 55Amps rated FET should survive this" - Yes, it did, and the fuse also. But the trace on the board did not:
My opinion, this is a shitty design. At least they should use thicker foil on this type of board. It is power electronics admit it or not. I soldered it together and the head started to heat.
Now comes some acetone and screwing the head together.