blobs on purge Tower  

RE: blobs on purge Tower

Me and my colleague have the same issues. We tried everything you can think of. Nozzles, maintenance, speed, temperature, more passes during wiping, etc. etc. Prusa team will tell you to use multimeter to measure termistor. Just another bug/error that nobody is willing to fix...

I started discussion here: link

RE: blobs on purge Tower

I've been batteling the blob for 2 weeks now. I tried all the tips i could find and did not resolve the problem. I've been printing creality PETG, because it prints fine and is cheap. After i built the MMU3, problems started like i said. Today I was testing (again) and decided to increase the temp above creality's spec ( 130c). I went to 165C on all 5 colors and was amazed by the result! Blob is gone,and i am amazed by it.

I hope some of you guys get the same results as i did.

Good luck!

RE: blobs on purge Tower

Henk - What temperature did you go with? Surely not 165C

RE:

Posted by: @henk-h

I've been batteling the blob for 2 weeks now. I tried all the tips i could find and did not resolve the problem. I've been printing creality PETG, because it prints fine and is cheap. After i built the MMU3, problems started like i said. Today I was testing (again) and decided to increase the temp above creality's spec ( 130c). I went to 165C on all 5 colors and was amazed by the result! Blob is gone,and i am amazed by it.

Surely you mean 265C, not 165C.

RE: blobs on purge Tower

You're right. Stupid mistake.

RE: blobs on purge Tower

I went with 265C, and I am sorry for the mistake.

RE:

I find this problem everywhere on forums.

I have the same issue. Big print, small print everytime i get multiple blobs.

And a lot of nasty noise when it passes it when the last wipe. 

It is where the nozzle halts and waits for new filament. 

Why isn't bed lowered directly after the first unload wipe? It can be done.

Everybody knows when you put an soldering iron into plastic the stuff gets deformed.

I dont use the mmu often because of this reason.

I only load 5 spools in an drybox and this way print my project in sections.

RE: blobs on purge Tower

everyone, since i started using CHT nozzle i have had no blobs. I mainly got the blobs while using non CHT 0.6 and have had less problems using CHT

0.4 or 0.6 nozzles. maybe this helps any of you

RE: blobs on purge Tower

Ok. Maybe it won't ooze during the pause there?

Anyway prusa recommends this nozzle so i use it. I see no really performace difference between cht and normal. Price is even beteer and i don't care for the minutes i win.

RE:

Just came across this issue aswell.. kinda new to this whole multi material printing.. blob caused a layer shift for me, i'm guessing its a configuration issue in the project.
Which of the million settings is it? i'm guessing something to do with purge volume?

Minimal purge on wipe tower? my core one does a purge directly after loading the filament.. then it proceeds to blob more in the wipe tower. So theres double purge it seems. I have multiple extruders set with Single extruder Multi material enabled.

RE:

UPDATE: Found the culprit! after hours of staring at gcode...

Print Settings > Multiple Extruders > Wipe Tower > Extra flow for purging

This is set by default to 250% !!!!! who needs that much filament in a wipe tower? i've set it to 100% for now...

RE: blobs on purge Tower

Hi, 

you might give this a shot (not sure I fully understand the mechanism behind it, the only blobs giving me headaches are large binary objects 🙂 )

...the following piece of G-code in "Printers" / "Custom G-Code" / Tool change G-code:

G1 Z+10 F10000; avoid melting into wipe tower (-mn)

see here: https://forum.prusa3d.com/forum/postid/773816/