Specific problem trying to print multicolor objects
I've been struggling with the MK3s/MMU2s ever since my printer evolved to be one. I'm now down to one specific problem that is a showstopper.
I can print a first layer I'm proud of. It's uniform thickness everywhere, and when it's removed from the printbed, it's like a thick piece of paper. You can't rip it, and it's as smooth on the top as can be. This applies to single material and multi.
If I were to print a single color, I have absolutely no problems at all. Again, a print I am proud of. No strings, no lumps, no deformities.
If I attempt to print a multi color, then I get a good wipe, but there are voids on the second and subsequent layers, almost immediately. What I do notice is that I start to get a ball at the back end of the extruder that starts catching the filament, preventing it from making contact with the already printed layers below.
What's causing this? Is it the fan? Do I have a partial blockage? I doubt it's blockage, as I have tested extrusion direction. Filament falls straight down when I raise the extruder and "Load to Nozzle".
This one has me stumped. If I got bad second and subsequent layers during a single filament print I think I could figure things out, but this is odd.
Best Answer by x50arm:
Maybe raise your filament temp and see what happens. Filament temps for MMU are lower than single material print.
RE: Specific problem trying to print multicolor objects
Maybe raise your filament temp and see what happens. Filament temps for MMU are lower than single material print.
RE: Specific problem trying to print multicolor objects
I bumped the extruder temperature up from 230 to 235 during a print using Inland PETG (box says print Temp 225-240) and it did better, so I think you are on the right track. I still had some errant strings and voids, but at least I was able to finish a print and deem it usable. I still have a way to go before I feel like I'm dialed in. Thanks for the tip. I've been repacking bearings, oiling rods, using a microscope to look for print 'hairs' in the extruder gears, etc. It would have been a while or never before I would have played with altering default profiles for plastic types.
RE: Specific problem trying to print multicolor objects
I bumped my non first layer temp up to 240 and am printing perfectly. An additional ten degrees did the trick.