Success with Hatchbox PLA and Multi-material?  

Success with Hatchbox PLA and Multi-material?

I was having an awful time with getting anything to successfully print with my new Muti-material add-on. I read and re-read all of the instructions and tips, rebuilt the extruders several times and was about to ditch everything and go back to my previous extruder...then I thought I'd try some of my original Prusa PLA filament. Followed everything here especially ( http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html ) and did 1-11 several times. Again I was working on troubleshooting a single extruder with a single filament and not trying to multi-color print. It is worth noting, however, that I did print one of the pre-sliced bearings using a hodgepodge of filament, and it worked mostly but was too tight to move. However any of the Hatchbox was giving me trouble.

Changing nothing, using same slicer settings, printing the same failed part i tried to print and it worked flawlessly, not once, but several times.

I had previously been using Hatchbox PLA with some decent success on the old Mk2 setup, but with this MM setup, it's just not working.

Symptoms would be, a decent prime line with no noise from the extruder, once it started printing the first layer I'd get the dreaded clicking noise, which seemed to be caused by retraction. I tried slowing the retraction speed down but it didn't seem to make a difference (or was being ignored). Just a few seconds into the print the filament would just get chewed up and then as a result would get stuck in the extruder (before the stainless steel tube) and I'd have to unscrew the PTFE tube from the mixer and pull (rather vigorously) to get the piece of filament out of the mixer.

I was printing my normal 205c but increased all the way up to 240 in an attempt (wrongly probably) to find out why it was binding so much. I had the extruder springs loose, tight, in the middle and nothing seemed to help.

It's worth noting, while doing this, I'm only trying to print from a single extruder, I'm not trying to do anything fancy.

I even opened up a brand new spool of Hatchbox white PLA (was using existing black and yellow, both stored in air-tight containers with telltale desiccant (white so no moisture). So I think I can eliminate environmental as being the cause. This Prusa PLA was stored in the exact same container, so...

My last attempt was to print the temperature test G-Code provided by PJR in his very helpful post ( http://shop.prusa3d.com/forum/original-prusa-i3-mk2-multimaterial-f26/blockage-troubleshooting--t4643.html ). The Hatchbox filament got past the prime stage and then failed to reliably extrude on the first layer (clicking/chewing up filament as far as I could tell). Again, the filament had expanded larger than the steel tube and I had to remove it manually. I then Switched over to the Prusa Filament and it printed it flawlessly. I then printed 2 other models and they printed just fine (where every attempt with Hatchbox failed).

The filament measures a little under 1.75mm for all the hatchbox in different areas according to my calipers, about the same for the Prusa Filament... The Hatchbox definitely seems a little more brittle than the Prusa.

Thoughts? Or is there a better filament I can get? I love the Prusa filament, but ordering that from Czech isn't that practical, though I would gladly if I could get the shipping cost down.

I was able to get Taulman PETG to print just fine, though stringy as crazy, but it at least printed reliably. And PETG would seem to be a bit more fiddley, but I think it handles the extruder abuse a little better.