I just received this machine and I now fear the nozzle is clogged. No filament comes out.  

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

If you cant see filament with the drive gear door open, but there is still a blockage, then the filament is stuck in the white PTFE tube below the gears inside the extruder, but above the heater block. You need force to push rhe filament down to the nozzle, where it will then melt and extrude, just like a glue gun. You cannot exert enough force with a pla string manually, thats why using a slim allen key which you can slide down the filament path past the drive gear into the ptfe tube. There is no room to go past the 1,75mm filament.

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

This must be the case.

If none of these methods work, it means that the tip is not touching the part of the hotend that is heated, and is stuck in the PTFE-tube. In this case you must extract the PTFE-tube.

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

I´d think it´s pretty improbable that there is PLA stuck in the tube in a way which prohibits you to push it down to the heated end of the extruder, using a well-fitting allen key or wire and some decent force. If you insert an allen key from the top of the extruder, past the gears into the PTFE tube, it means the path is clear so far. Before you proceed to pull the PTFE tube (there´s usually spares in the spare part pack), go back to square one. Close the gear door and get some pressure on the door as per manual. Next, heat the nozzle up to 250 degrees via menu. Then insert regular filament (PLA, PETG,... but no gimmick filament like flex stuff etc.) from the top through the regular pathway and select "Load Filament" if you have not activated the filament sensor. The gears will then have to get a grip on the filament, as there is no blockage up there. Next, the filament will be fed into the PTFE tube by the gears and be pushed down. Now, either there is no filament stuck, then the new filament will extrude. If nothing extrudes, just answer the question "right color extruding?" with "no" and the gears will again get into action. If there still is no filament extruding, there is apparently a blockage. Before you remove the filament again, open the gear door, check that the filament is passing the gears into the PTFE tube, just to be sure. Close the door as per manual, and hit "unload filament". When the filament is being pushed up to the top, pull with some force, but balanced force, no hard ripping. The newly inserted filament should come out fine. Then I guess it´s time to take the next step in the manual, removing the PTFE tube.

I understand this is a nuisance, but take it as a piece of the learning curve we all went through; this won´t be a recurring issue over time, and you´ll get to know your printer.

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

Some notes on clearing filament jams in the extruder here. Written for the Mk3, but easily adapted to the Mk3s. A 1.5mm X 15cm length of brass rod is a lifesaver!

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

@just3d

I am sure white tube is clogged and needs to be replaced. I cannot get heat sink out.
It seems one would have to separate the two halves of the black plastic housing around it but it doesn't come apart I don' think.
Is there a trick to getting it out so I can change white tube?

Thx

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

@darcshadow

I am sure white tube is clogged and needs to be replaced. I cannot get heat sink out.
It seems one would have to separate the two halves of the black plastic housing around it but it doesn't come apart I don' think.
Is there a trick to getting it out so I can change white tube?

Thx

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

I am sure white tube is clogged and needs to be replaced. I cannot get heat sink out.
It seems one would have to separate the two halves of the black plastic housing around it but it doesn't come apart I don' think.
Is there a trick to getting it out so I can change white tube?

Thx

RE: I just received this machine and I now fear the nozzle is clogged. No filament comes out.

I've had this happen a few times now, is there a secret to avoiding it?

Posted by: @justme3d

I´d think it´s pretty improbable that there is PLA stuck in the tube in a way which prohibits you to push it down to the heated end of the extruder, using a well-fitting allen key or wire and some decent force. If you insert an allen key from the top of the extruder, past the gears into the PTFE tube, it means the path is clear so far. Before you proceed to pull the PTFE tube (there´s usually spares in the spare part pack), go back to square one. Close the gear door and get some pressure on the door as per manual. Next, heat the nozzle up to 250 degrees via menu. Then insert regular filament (PLA, PETG,... but no gimmick filament like flex stuff etc.) from the top through the regular pathway and select "Load Filament" if you have not activated the filament sensor. The gears will then have to get a grip on the filament, as there is no blockage up there. Next, the filament will be fed into the PTFE tube by the gears and be pushed down. Now, either there is no filament stuck, then the new filament will extrude. If nothing extrudes, just answer the question "right color extruding?" with "no" and the gears will again get into action. If there still is no filament extruding, there is apparently a blockage. Before you remove the filament again, open the gear door, check that the filament is passing the gears into the PTFE tube, just to be sure. Close the door as per manual, and hit "unload filament". When the filament is being pushed up to the top, pull with some force, but balanced force, no hard ripping. The newly inserted filament should come out fine. Then I guess it´s time to take the next step in the manual, removing the PTFE tube.

I understand this is a nuisance, but take it as a piece of the learning curve we all went through; this won´t be a recurring issue over time, and you´ll get to know your printer.