jsw

I would like to give Dynamism a Gold Star (tm) for not gouging on repair parts. Some time ago, I had prints failing due to an inoperative print head fan. It was a broken connection, so easy to fix. However, the other day it started the same thing again, and I noticed that the fan was not spinning. Disassembly showed a lot of environmental cat hair (yes, yes, I know) stuck in it, and although I can clean that out, I thought it would be a good idea to replace it with a new known-good one to avoid the masochistic disassembly of the print head yet again. Being che^H^H^Hfrugal, I first checked Amazon with the Sunon part number, thinking they would probably be cheaper. $47-ish for a new fan on Amazon. Then I checked Dynamism and it was $19 and change, less than half of Amazon's price! Thanks again to Dynamism. 😉

Yes, mine was a disconnected wire too. Lesson learned.

You're very welcome. This was a quirky one, and a lesson learned in overlooking what should have been obvious. I'm usually very confident in troubleshooting 3d printers, but this one had me stumped. Thanks again to those who helped out. This explains another quirk, which I did not include in my original item simply to avoid overloading and what I thought may be confusion. Again, lesson learned, all details may be relevant. Once when I was changing filaments, the filament would not unload. When I removed the bowden tube from the print head, it was obvious that the reason it would not unload was that there was a bulge in the filament, preventing it from moving through the tube upon an unload request. (Photo below, look closely.) It only happened once, and now I realize that in the other cases I removed the filament before things cooled down to the point that the deformed filament was solid. In this case I obviously waited a while and the filament cooled and prevented the unload from happening as expected. Thanks again. Hopefully this exchange will be searchable and will help others with similar problems.

Well, it looks like the fire may be out. Thanks to everyone, in particular to gr5 and Torgeir. It looks like the culprit was the fan, and I'm actually surprised that I did not notice that the fan was not spinning. At least the trivial print printed as expected. Now to try some 'real' prints. Thanks again.

Thanks, but I think I have the mystery solved. I was using the low-tech method of a dental mirror and flashlight in an awkward set of positions, and I finally realized that if I would simply slip the phone in there, turn the flash on, I might be able to capture the markings on the board, which I did. As you can see, the second connector from the left is clearly marked 'Sensor', so when I get a chance this afternoon or evening I'll be able to put the thing back together. Thanks again.

Thanks, GR5. As you will see from the photo, the one wire to the fan had broken off, obviously rendering it inoperable. I resoldered it and the fan spins up properly on a bench supply. I also removed various cat hair and other environmental gunk, and it spins freely. Now, as I removed the assembly, I neglected to write down the order in which the sensor and the fan are connected to the rear of the print head assembly. Even with a dental mirror I can't see obvious markings. Would you please be kind enough to tell me the order (looking at the print head assembly from the rear) the fan and the sensor are connected. I don't want to get these backwards and risk damaging something. The two side fans are still connected, I just need the left-to-right order of the sensor and fan that are in the print head cover. I tried googling for the connections, but came up empty. Thanks again.

Thanks for the responses. before I dump the logs, i will inspect and carefully clean the front fan.

thanks, will do

Thanks, which logs, specifically (IIRC, there are many files) do you want?

And I just did a good cold pull on one of the other AAs, same thing, loses extrusion midway during the first layer. I'm going to contact Dynamism support on this, as I am totally stumped.

Also, this is currently losing extrusion, not printing in the air or printing squished against the build plate. One of the areas where the extrusion is poor on the flat piece is dead-center, where the successful print of the post occurs.

I have used three different known-good AA .4 print heads and one known-good AA.25. One of the .4 ones was cold-pulled and needled to be sure.

Unfortunately it's about the same. The vertical post prints perfectly, the small flat piece loses extrusion shortly into the first layer.

Another update, I just updated to 7.0.3 and there was a yellow (!) warning suggesting to update to 7.1.3 as it fixes a bed leveling issue observed in the field. Downloading 7.1.3 now.

I ran the bed leveling test and it passed. Ditto with the sensor switch test. I'm currently downloading 7.0.3 and will version the box as a next step. If the issue persists I'll probably phone or write Dynamism support tomorrow and I'm sure one of the first things they will ask is if it is running current firmware.