Separation between lines at bottom and top surfaces  

Re: Separation between lines at bottom and top surfaces

Hi Victor

First thing to do is to print one of the pre-sliced gcode files provided on the SD card by PR.

That will determine whether it's a printer or slicer issue.

Peter

Re: Separation between lines at bottom and top surfaces

Hi Peter,

Sorry about the long time I took to reply, was very busy these last days.

Well, I tried to print the PRUSA logo, and the problem persists as you can see on the image I took during the print .

there is some separation between the lines, I've already checked the belt tension and it seems fine.

Edit: I forgot to mention, sometimes while printing I hear some weird noise that appears to come from the extruder like a hitting sound, very dry I tought it was because the bed was too high and the nozzle was hitting something but after a while I realised that nothing was being hitted. Could this be something with the nozzle?

Regards,

Victor

Re: Separation between lines at bottom and top surfaces

Hi Victor

The noise you hear is the filament skipping - pushing backwards against the extruder drive gear.

Given the issue you have with the skipping, a nozzle clean or replacement is in order. You may also need to change the PTFE tubing if that is burnt or damaged.

Best cleaning method is here (adjusted for this printer): https://ultimaker.com/en/manuals/149-atomic-method

When you pull the filament out, if the end of the filament is very black or not regular, then you will have to take the extruder apart and remove the PTFE to check if it is OK.

Peter

Re: Separation between lines at bottom and top surfaces

Thanks for the tip, I'll try it and post the results here.

Just two quick question, when I'm pushing the 20cm filament piece in should I do that with the screws that press the bearing against the extruder tightned or not?

On the case of the prusa printer I do not remember this clip holding the PTFE tube to remove it, should I do the cleaning with the tube on anyway or try to take it off?

Regards

Re: Separation between lines at bottom and top surfaces

Hi Victor

Remove the 2 screws and swing the tensioner out of the way. Ignore the tube instructions; that is the Bowden tube used to get the filament from the spool to the extruder which is not present on the Prusa i3. There is a small PTFE inside the extruder which needs to remain in place when you do the cleaning. However, if the filament has some black deposits on it when pulled out, it may indicate burning of the PTFE tube which may then require replacement.

Peter

Re: Separation between lines at bottom and top surfaces

Hi,

I did the procedure you mentioned, the first time I think I did something wrong because I did not had to put any effort to take the filament off. However on the second attempt It came off offering some resistance, the tip of the filamente was conical well shaped, I noticed some holes in the filament though. Then I did the procedure again and the filament came off with no more holes and the tip was very well shaped so I do not think this is a problem with the nozzle. Do you think this could bed calibration? (too far, so the filament is not spreading as it should? ) or something else?

Regards

Victor

Re: Separation between lines at bottom and top surfaces

Hi Victor

OK, next step is to get the calibration (distance between nozzle and bed) absolutely correct (0.23mm). Then print one of the supplied files again to see if that is any better.

Peter

Re: Separation between lines at bottom and top surfaces

Victor

Just looking again at your pictures. Are you using the glass sheet or is the blue tape applied directly onto the heater?

If the latter then you will be struggling to get a good calibration as the PCB is not particularly level.

Peter

Re: Separation between lines at bottom and top surfaces

Hi Peter,

I've not had the chance yet to re-do the callibration and test again as I'm out of town. I'm using blue tape on the glass, do you think is something related to it? I've done a few prints before that did not had this problem using the tape.

Re: Separation between lines at bottom and top surfaces

Hi Victor

For difficult parts, I also use blue tape; if can be easier to get very large parts to stick to blue tape, but the temperature must be 50 degrees or less with the tape.

The only reason I raised that point was simply because I could not see the glass in your photos.

Peter