This needs further experiments but at the moment it seems that:
If the print job is single color, filament load from AMS and printing works just fine from start to finish.
If I use external spool for single color print, (manual) filament load and print works just fine.
If the print job is multi color, filament load from AMS fails usually straight away. AMS has huge difficulties to pull the filament (skipping) and it does not exit the AMS. After few tries, error message comes up saying something about high resistance etc.
If I try again, and push the filament in with my hand while AMS is trying to load it, the filament eventually loads to the extruder and print starts.
After that, the print may continue for hours, but sooner or later it will fail again with same error. Sometimes filament change works, sometimes not. I can make the print to continue with manual intervention, but of course the printed object is not perfect anymore and I have to babysit the damn machine.
One curious detail: loading the filaments in the AMS is fine (i.e. put the roll in, push the filament into the feeder, the AMS pulls the filament in and pushes it near the filament buffer and pulls it back with no problem).
Printer is H2S AMS2 Pro bundle, only about 1 week old. Filaments are generic PETG, nice and dry. Problem occurs on all AMS slots (I first thought its just slot 1, but that’s not the case).
Any help is most welcome. I will raise a BL support ticket after I collect a bit more evidence…
Mine does the exact same thing. Brand new printer and ams 2. Yet i cant do multicolor because it constantly fails to load the new color. I submitted a ticket because i couldnt find a fix.
Been pretty busy, but had time to do one multi-color test print (only 30 mins). I unloaded and reloaded the filaments in AMS first. Print went fine, no errors. Next, I will do the same print without unloading/reloading the filaments.
How is your cabling of the PTFE tubes? short/long distance and no/lots of bends?
I have build an AMS cabinet and while my PTFE tubes looked “normal” when I peeked inside the cabinet I saw one AMS had quite some bends - it still worked for me, but I guess it was on the limit… I now shortened the PTFE to reduce the bends.
My AMS is sitting on the printer and PTFE tube from AMS to printer has no tight bends. Tube length is not modified - I might try shorter one when I get some spare tubing (so I can quickly change back if things get worse). I’ll have to re-check the tube length from buffer to extruder. But problem there does not explain why AMS sometimes fails to push filament out at all.
I raised a ticket with BL. Amazingly, since then there has been no issues with AMS. They are waiting a video of the problem, but the AMS is working fine atm. I have done several one- and multicolor prints (print duration between 15 minutes to 7 hours). All good.
BUT! I have made one change just after raising the ticket: The power chord from the printer was originally connected to multi socket extension cable which was connected to another multi socket extension cable which was connected to wall socket. I replaced the two extensions with one heavy duty multi socket extension cable connected to wall socket.
Time will tell if the more proper power supply cabling was really the fix.
If any of you have unexplained AMS 2 Pro problems (no exteme bends in pfte tubes, no blockages, no broken parts) it might be wise to check power supply cables/configuration. Or try external power supply with the AMS.