Top of print ugly.  

Re: Top of print ugly.

I guess you print from PLA. If you print more copies of the object at once (together), is there the same problem? If not, insufficient cooling might be the issue.

Re: Top of print ugly.

Mark

Are you slicing your own models? If so, do you have the part cooling fan turned on? If you do, then check it is working properly otherwise turn it on 100% after the first layer. And slow down the print, maybe increase the minimum layer time.

Try printing the Marvin or Tree Frog from the supplied SD card. If they have the same problem then you have a hardware issue.

Peter

EDIT

Also check the grub screw on the filament drive gear and ensure it is tight.

Re: Top of print ugly.

I am slicing my own models yes. Just started another marvin print and it ended up clogging the nozzle. Twice in 2 weeks since I upgraded to the MK2.

This e3d full is horrible to be honest, never had a problem in my 8 months of ownership of the MK1 with the lite. Seriously disappointed.

Re: Top of print ugly.

Mark

My opinion is that when the V6 is used properly it is an extremely good hot end; so good that I installed one in my Mk1 within a month of purchase and that is still working extremely well.

The V6 allows almost twice as much filament to be melted which in turn brings many benefits. However it is different to the Lite6 in that the slicer needs to be set for much lower retraction (0.8mm) otherwise blockages can occur. Because of the longer PTFE tube in the Lite6, higher retractions could be used (although in the main not necessary) but of course that also meant lower temperature were essential.

Having said that, I have a suspicion that not all the V6 hot ends are being assembled perfectly before shipping. You need to check that the PTFE tube has a perfectly square end (at the heat break) and that it is fully inserted and locked in position.

Hope this helps.

Peter

EDIT - back to the topic - did you tru printing a pre-sliced part?

Re: Top of print ugly.

Yes, it clogged the nozzle within 15mins 🙁

Which now I have to spend close to 2 hours to clean. And if it's supposed to be set to 0.8mm why doesn't the profile come with that setting? 😕

Re: Top of print ugly.

In that case, you may have an issue with the PTFE tube as I described above or you are using an old pre-sliced model with larger retraction. The models released with the later drivers have (I believe) lower retraction settings.

Peter

Re: Top of print ugly.

Having said that, I have a suspicion that not all the V6 hot ends are being assembled perfectly before shipping. You need to check that the PTFE tube has a perfectly square end (at the heat break) and that it is fully inserted and locked in position.

When we got our MK1 the V6Lite was giving me us no end of problems, it turned out that it was very badly assembled, the PTFE tubing wasn't installed right, the heatbreak was screwed too far into the heat block, which then meant that the nozzle could only screw in about 1mm before it seemed locked tight. The result was filament was pumped out all around the thread of the nozzle gumming the whole thing up! When disassembled the PTFE had melted into a blob!

Still, these things happen and Prusa exchanged it for a new one so all was right in the end... Can't let the odd defective one spoil the fun!

Re: Top of print ugly.

Ok guys, I'll check the tube tomorrow. Such a pain to disassemble the extruder 🙁

Should've just stayed with the mk1 :p

Re: Top of print ugly.

Still, these things happen

Yes and no criticism of Prusa Research here at all. We are all human and make mistakes and putting together hundreds of these things must be so boring it becomes very easy to make a mistake. But it is easily remedied. I think it took about 15 minutes for me to get it sorted when it happened and it's been perfect since (even with 1.5mm retraction).

Peter

Re: Top of print ugly.

Thank you Peter, will try adjusting the tube.

Re: Top of print ugly.

Mark

I certainly do understand your frustration with the Mk2. I hope you will believe me when I tell you that the Mk2 is a significantly better printer than the Mk1, even though that was excellent.

I am printing things that were simply not possible with the Mk1 and the V6 has allowed me to print a lot faster - for some items I have been printing perimeters at 100mm/s with 0.2mm layers although I do print a lot slower when precision/quality is required.

I used to spend a few minutes calibrating the Mk1 each week, but that is gone now; the Mk2 just keeps on churning out prints without issue.

However, to get to this point was also frustrating for me; there were a few things to overcome and I had to understand just what was going on before I could really use the printer.

Peter

Re: Top of print ugly.

Hi Peter,

As always thank you very much for the help. I will clean the nozzle up, fix the PTFE tube, reduce retraction and give it another go tonight.