Weird clogged extruder type deal, but not

[Cyber_Gram]

Hello,

I am a new (and proud) owner of an M2 3D Printer (My first 3D Printer) and after my 3rd print I ran across a weird problem. I started my 4th print, then stopped (to re-size the print) by turning off the power supply, since I didn't feel like waiting for it to pause and then having to press restart and go over the whole process to stop and start a print (Also because I sorta couldn't find how to stop a print in Pronterface, but now I know how to ). Now whenever I go to print an object, the first few layers won't print, then it'll start to extrude filament. Two things that makes me think this is not a clogged nozzle is because when I do manual extrusion via Pronterface, it will work. If I try to push the filament through while it is printing the blank layers, it seems to make it start to extrude, even after I stop pushing it through. The nozzle/bed has reached the set temperature, by the way, and the stepper motor for the filament is moving. Another weird thing is that whenever I start the print, it'll home XYZ, then go off to the right side of the build plate and lower the build plate, almost like it is heating up the nozzle/bed. When it is on the right side of the build plate, it will also extrude some filament (Also, it is practically extruding filament right onto the fan in the controller box thing). After it is done extruding some filament, it will start the print. Like I said before, the first few layers will be blank, then it will start to extrude filament. Whenever I print the stock bigfoot head in the SD, it will lower the build plate all the way down before it starts to extrude. Whenever I print the stock bracelet in the SD, it will just not print the first few layers, then start to extrude filament. I don't blame you if you just got confused .I will upload a video of what is going on, if requested. Thanks for the awesome printer Makergear, and I hope I will be up and printing soon! (Also, how do I control fans in Slic3r? )

Thanks,
Cyber_Gram

[Jules]

I don't use Slic3r, but the business that you are describing where the nozzle moves over to the right side of the bed and squirts a little bit of filament, then moves back over to start the print is a standard purge code that is written into every print startup. It extrudes a little bit of filament off to the side to prime the nozzle and get the filament loaded and flowing. Then it drags itself across the plate to wipe the nozzle before starting the print itself.

It's supposed to do that. If the nozzle isn't primed before the print, the first few layers are going to be blank. It's not actually going to land in the fan, but if it makes you uncomfortable, you can do what most of us do, and just catch the purge with your tweezers.

[Cyber_Gram]

Okay, maybe I just never noticed the priming thing, but what about the not printing the first few layers thing?

[Cyber_Gram]

Okay, maybe I just never noticed the priming thing, but what about the not printing the first few layers thing?

Sorry for the double post, but some objects, such as the bracelet and the tallthin don't have a priming stage.

[Jules]

Try re-setting the machine. (Turn it off, turn it back on - I'm not sure how Pronterface works, but if i shut it down mid-print it messes up the USB connection and i have to start over from the beginning, including restarting S3D.)

And if a particular file lacks the startup priming instructions, you can always extrude a bit manually to prime it yourself.

Usually when you load the filament, you'd purge a hundred mm or so through to make sure it's primed and flowing.

[Cyber_Gram]

I've restarted it multiple times now

[Jules]

Without trying to print anything, purge several hundred mm through the nozzle to make sure that it is clear, (100mm at a time for PLA). If you are getting a good stream coming out of the nozzle during a purge, you don't likely have a clog.

So that might mean the file was corrupted, or maybe someone who uses Pronterface and Slic3r can come up with another idea of what it might be. I'm assuming that since you were able to print several items successfully that your gap is set correctly.

Try printing a couple of different files and see if the same problem exists, or if it is just the one that keeps dropping the layers. That is going to be the easiest thing to check.

[insta]

Your drive teeth are clogged, for reasons I can't quite figure out.

Heat the hotend, back the filament out entirely (you'll need to provide a gentle tugging pressure), then swivel the fan out of the way. Blast compressed air straight into the teeth on the filament drive, the stronger the better. I have some "industrial canned air" I got from MicroCenter which works well, better yet is if you have an air compressor with a squirty nozzle thingie. Don't bring that weak-ass Walmart canned air game. You should notice a confetti of plastic come shooting out of the filament drive. If it doesn't, unscrew the fan & filament drive and clean the teeth with a scrubby brush.

Before reinserting the filament, loosen the tension screw a lot, feed the filament in (make sure there's still a gap between the tension washer and the filament drive), then tighten it finger snug. Not finger tight, just finger snug. From now on, run your filament through a corn-oiled dust wiper. I use a piece of paper towel that I cut into a .5 x 2" strip, folded in half about 3 times, the 4th fold dipped into corn oil, then the 4th fold clamped around the filament with a small binder clip. This will keep the filament lubricated, the hotend "seasoned", and the combination will help prevent clogs.

[Cyber_Gram]

Your drive teeth are clogged, for reasons I can't quite figure out.

Heat the hotend, back the filament out entirely (you'll need to provide a gentle tugging pressure), then swivel the fan out of the way. Blast compressed air straight into the teeth on the filament drive, the stronger the better. I have some "industrial canned air" I got from MicroCenter which works well, better yet is if you have an air compressor with a squirty nozzle thingie. Don't bring that weak-ass Walmart canned air game. You should notice a confetti of plastic come shooting out of the filament drive. If it doesn't, unscrew the fan & filament drive and clean the teeth with a scrubby brush.

Before reinserting the filament, loosen the tension screw a lot, feed the filament in (make sure there's still a gap between the tension washer and the filament drive), then tighten it finger snug. Not finger tight, just finger snug. From now on, run your filament through a corn-oiled dust wiper. I use a piece of paper towel that I cut into a .5 x 2" strip, folded in half about 3 times, the 4th fold dipped into corn oil, then the 4th fold clamped around the filament with a small binder clip. This will keep the filament lubricated, the hotend "seasoned", and the combination will help prevent clogs.

I did what you said (Without the corn-oil thing, but I will do that after I make sure it is working) and now whenever I print anything the printer is extruding stuff backwards in a jumping action. (Not a good sound either)

[Jules]

Might be time to post that video. Filament shooting backwards sounds like it might be a partial block of the nozzle, or you are trying to extrude too fast. A clunking sound in the filament drive area might be the stripping of the filament in the drive, and the extruder motor is skipping. It means the tension on the screw at the top of the filament drive is too tight.

If you post a short video on Youtube of what you are seeing, (with sound if you can), it will make it a lot easier to diagnose.

To set the correct tension on the filament drive screw, you might want to read this:

viewtopic.php?f=3&t=2694