I guess I will check the hotend more carefully then. But regarding placing parts in the oven, which parts exactly do you mean?
In regards to too low a Z-offset causing extrusion failure, if the nozzle is too close to the bed then the pressure inside the hot end is higher due to trying to extrude a fixed volume of plastic into a smaller gap then there should be. This increased pressure resists the extruder pushing the filament and so can cause filament grinding. This is only usually the case when printing items with large surface area on the print bed or multiple items.
As I said in my post, this seems unlikely as you mentioned that the failure was occuring many hours into the print. As you said, it is most likely your retraction settings causing this problem!
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So I replaced my hot end and things are good again. One thing i noticed though that i wanted to share is that in looking at the old hot end the thermistor was practically hanging out of the heater block. I compared it to another hot end and I want to say the cable from the sensor to the connector was somewhat shorter. I question if this isn’t inserted enough maybe the temperature control was off resulting in a colder nozzle that doesn’t extrude?
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I was about to add that I am now seeing this issue - and your comment about “too much tension” could be what I’m seeing.
I just got the A350 case, and the standard spool mount for it is TERRIBLE and requires pulling the filament through a hole at right angles to source and destination.
I’ll setup an alternate spool mount and see if that helps.
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I agree about the questionable spool mount… someone posted an .stl model in the Facebook group, but I haven’t gotten around to printing it yet and I don’t know if it would reduce the tension in the filament.
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I’ll be doing something similar. (though with more testing, I’ve found that isn’t causing the problem with feed stopping. Problem was solved by replacing the Hotend.)
I’ll probably make a minor mod to the spool mount I already made for my SM1, and drill a small 1/4" hole in the middle of the top, right over the printhead.
Just need this a bit wider to allow the user of a auto-rewind setup.
I’m happy to report that the last print worked out very well!
I cleaned the nozzle properly and edited the retraction settings as advised.
Personally, I don’t think the nozzle or the filament itself was the problem; I’d rather attribute this to the retraction settings.
In any case, let’s hope this won’t be an issue going forward.
Many thanks to all who provided advice here! 
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while this might be off topic i think it could be related, i was having really bad stringing issues and needed to set the retraction to 7mm. but i was worried about clogging, so i continued to investigate and found that the thermistor is not secured into the heat block. i believed this was causing some inaccurate nozzle temps (as @Marek noted), so i applied a small amount of thermal compound into the hole. Since then i was able to lower my retraction considerably (down to 4mm). while stringing is not your issue, i would imagine that if the heat block is not holding a proper temperature it could also cause other flow issues (such as the grinding described earlier as well as clogging of the nozzle). maybe try it and see if it helps?
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Hey All, I’ve just had a print fail 30hrs in. All my previous prints even the multi day ones Iv had no issues with at all.
As mentioned in the last couple of posts Iv stated to notice a little stringing as well before this happened today.
I will check the nozzle and clean it, but i was wondering what extatly did you do or change with the retraction settings?
Sorry complete nooby here 
I set my retraction to 3mm and retraction speed to 40mm/s
Others have gone as low as 1mm retraction.
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As @Atom mentioned, I’ve also stuck with similar retraction settings.
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Ciao all, I just got the A350 and I have the same problem: after about 1/2 hour of printing the filament doesn’t come out anymore. I will try your suggestions regarding setting the parameters, but I wanted to know how to change the printhead. Where can i find information on how to disassemble the 3D module?
I woudnt take apart the Module until Support tells you to. Youll void your warranty.
If you take out the Filament, did the gear dig a trench into it? When the printer stops extruding, will manualy pushing the filament work or is the whole nozzle assembly cool (maybe dont touch it directly to check?).
Removing the hotend is quite easy, you open the filament door and near the bottom there is a black grub screw. Loosen that and the hot end will drop out the bottom. Disconnect the connector and pull it out.
From their blog here: https://shop.snapmaker.com/blogs/blog/another-new-feature-added-upgraded-design-of-the-snapmaker-2-0-3d-printing-module-test-progress-1
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@anto you can change the hot end as described by brent113 without voiding the warranty.
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yes you are right. On filament there is a trench due to gear dig and I note that there is mechanical tension from filament spool to 3D module. I used A350 enclosure and I think the filament logistic is very bad. For that I planned to put a new filament holder on enclosure ceiling over the 3D module.
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I had a print air print half way through and want to try this method. Do I delete everything in the file above my z=“current print height” or do I have to keep some of it, such as the header, for the printer to know how to proceed?
If you have a SM2.0, I would suggest to keep the start gcode and delete the lines between start gcode and your z-height.
Give the printer some attention at the first layers with the hand to power off, if possible 
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I’ve had my A350 up for less than a week and have had two major blockages
These are images of what I end up with. When the printing stops I do an unload - the filament comes out all hot and melted, but after things cool down and I take the nozzle off I find a piece of filament broken off inside… This has happened with both factory hot ends. I ordered a few nozzles from Amazon, but have het to try them.
I have my retraction settings at 1mm @ 25mm/s.
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