Recommendations on JustPLA parameters?

Recommendations on JustPLA parameters? I’ve purchased a number of rolls of PLA…the Yellow prints just fine…the White and Green Sea are pretty much guaranteed to have prints fail or look porous. Been running at 200-205C

Sent an email to the vendor (granted, it was just one) but didn’t hear back and I couldn’t find any recommendations on their site.

In a related question: How do you consistently set the tension of your extruder? Is it a count of turns, measurement of distance, or blind luck? :slight_smile:

If your prints are porous at 205 you probably don’t have enough your extruder tight enough. Either way, more heat probably won’t help. I usually do a maximum of 200 for the first layer and 190 for the print, ranging speeds from 60-100.

How fast are you printing? What hot end? What extruder?

Some extruders are spring loaded and some are not. I imagine the manually set tension extruders are set to a a tension just before it starts giving resistance, but that is just a guess. My current extruder is spring loaded.

Different colors of filament (or the same color by a different supplier) will have different amounts of dye and filler. Some colors (like black) may have a larger amount of dye or filler than others.

It’s an E3d, and the printspeeds are in the neighborhood of 30mm/s or so. I’ve homed in on 205C on this printer from general experimentation, I expect my thermister is reading slightly high. The extruder, at times of failure, is on the ragged edge of carving a notch in the filament.

I’ve noticed, at least with the Sea Green, that it’s REALLY soft and easy to bind up in the extruder assembly.

@Mike_Miller :

  1. tighten your extruder. DON’T overtighten - too tight and you will smoosh your filament into a oval shape and cause extra friction in the hot end. Yes, smoosh is a highly scientific and technical term.

  2. LOWER your E3D temp by 5-10 (seems counter intuitive, but my E3D jammed WAY more when it was running too hot)

  3. CANOLA OIL: unload your filament, dip the end in canola oil and load it back through the E3D. This will season the inside of the extruder and give it less friction! Just like when you season a pan for cooking for non stick! Also your prints will taste better!

I’ve seasoned the extruder, I’ll lower the temps. I know for a fact it won’t push out at 180C, where some people say they get the most detailed prints. For all it’s initial problems, I’ve got a spool of Makerbot Orange that’s been open for months…it just keeps 'strudin at 230, print after print.

yeah, seems like something is up… you should definitely be able to use it at 180 with PLA. Maybe inspect the barrel for problems?

I doubt it, I’d just written it off as a temp calibration issue, as I’d had successful prints from other filaments.

I run justpla stuff all day at 220-230c. In my e3d. Print speed is somewhere around 80-90mm/sec. With an airtripper Bowden. I have more issues when I run slow it seems.

That’s what I love about this hobby…and by love I mean “am entirely baffled by”…certain parameters work for certain people, and other people have found entirely different parameters that work for them.

@Mike_Miller check filament diameter. I had some justpla up to 1.87mm in spots jamming things up from friction point due to lack of clearance.

So what do you do with that? (run sand paper? :D)

@Mike_Miller I get the feeling that air pressure, air temperature and humidity level have something to do with extrusion results.

Do you use a fan on your prints and cooling barrel(that leads to the cold end)? People have said they get great improvements on PLA using fan ducts.

things fail at roughly the same Z-level when using an active fan, I’m thinking of shrouding the hot end (rather than adding another fan to the effector and relying on the printer to print a fairly complex fan shroud…

Yea JustPLA isnt great with their dimensions. Im not using a cooling fan of any sort other then the typical e3d fan. What extruder are you using?

It’s a Wade type with hobbed bolt and has worked for hours on end with no issue. So now I’m switching to ‘if in works okay in certain situations, how do I discover the situations where it doesn’t work well, and how do I avoid them?’

Hows your bolt doing? I had issues about a month ago where after a few months of use all my hobbed bolts went bad right at the same time. The PLA I was running dulled/shredded the teeth.

Sounds like I need to print the Hob tool next. :confused:

Heh. You could always print a squirrel cage fan and use a tube to funnel the air if you want more cooling power. I have not tried that yet, but I think some have.

So here’s the odd thing. I threw the owl at Cura, in mouth-breather mode. 3:45h in, at 220, and it hasn’t failed yet. (Z=48.60 mm)