Problem with Part cooling Fan

Hi Guys…

i’m not sure but i think i have a problem…

if i turn on the snapmaker for printing (extruder&bed off, home position) the part cooling fan is running. by sending gcodes via Luban (serial, Wifi) and octoprint the fan will not do what i’m sending.

If i send M106 the fan has the same speed like turning on snapmaker. if i try M106 S0 the Fan becomes max. speed. not all values (1 - 255) for S are working. if i send M107 the fan becomes faster (equal speed to M106 S0) instead of going off.

all cases sending always back ok in terminal.

i’m not sure… maybe its a bug?!?

yeah, there are some bugs with the fan, but i think they are a little deceptive

There are two fans inside of the print head, one will run full time when the nozzle is on or hot, the other will run based on the M106 commands.

Terminal will always respond with OK via wifi connection, as it cannot communicate back.

Try to m106 the fan from idle for a different type of test.

i have noticed that leaving the serial port open will results in funny business for some reason after a job is done, but it will typically follow its instructions otherwise.

i think this is likely more related to luban than serial communication in general. there is some bugginess there, yeah, but i think its more related to the 2nd fan for cooling the board more than the part cooling fan. i say this because i added an external fan for cooling spliced into the same port.

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i know what you mean… and i also know the commands. But as i said… by sending command M107 the part cooling fan runs with max speed instead of going off. Every time i’m tested.

I had exactly same problem after adding a blower fan to the original port. How did you fix it.

I am not sure what we are talking about on this one to be honest. It was a long time ago when i monkeyed with the fans.

Some things have changed from then to now, in particular that you are able to receive feedback from the console via wifi

What exactly are you having a problem with? I can try to help. The original print head shipped had poor cooling and I have done several different mods to improve it.

The revised single print head had improved cooling but I didn’t use it often because I added a new sensor to the first one that Ididn’t want to hack into the 2nd (for printing on glass).

Today I now have the dual extruder which I am still having issues with.

I would be happy to goback and find some of what I did to make it better based on your response

Yea. Thank you so much for helping. I have the artisan with the dual extruder head, and I find the part cooling fan incompetent when printing overhangs. The corner always curl up and the extruder eventually would knock the part over. I tried to solve this issue by splicing a 5015 fan onto the original part cooling cord. However, the part cooling fan turns on full time now, and I could not get it to turn off. Also the heat sink cooling fan stopped turning on when I switch on the machine. It seems like the firmware got confused about these two type of fans.

There are two different fan ports inside the print head, at least on the original module. one of them is on full time and the other is controlled by gcode. you may try to switch your pslitter into the other fan port so it is controllable.

As for the curling, that could be an indication of too much cooling in actuality. not necessarily though.

I did splice onto the one that is controllable, but after I did that, the firmware now allows me to control neither of them.

I don’t know why that would be the case. Perhaps you have a short someplace causing the voltage to be on the fan full time, or perhaps something occured to fuse the transistor output in the on position.

if you remove your splicer does the fan shut off?

The removal makes no difference, unfortunately

Sounds like you may have accidently damaged the transistor output.

Try a factory reset to see if that helps?

Perhaps consider taking pictures of the board/wiring for review? Maybe something didnt get reassembled right and we can spot it.

I can’t spot any visible damage. If I just plug in the fan and connect the power, the fan start to spin full speed

I reset the machine and nothing happened. Do you know if there is way to reset the mother board to factory?

There is a factory reset routine through the menu on the screen, if you swipe the screen right to left and find machine information or some such wording youll find it someplace

I think in Luban there is a factory reset macro you can run as well.

I will give that a try. Thank you so much for your help! Worst case scenario I will just ask snapmaker to ship me a new motherboard.

Tech support told me the triode broke, probably because I unplugged the extruded head while the power was on. Thank you for pointing me in the right direction.

Hi @Jiaonasen ,

It seems I encountered the same problem. How do you fix it in the end? And do you know which triode is broken?

Thank you.

Its location Q5 or Q9. The triode is BCX56. I just asked them to send me a new motherboard from China.

Hi @Jiaonasen ,

But I don’t see Q5 or Q9 on the board. It seems we have different models. Mine is A250, single extruding.