Newb with multiple print quality issues

I’ve had my Mini for a couple of weeks now, and have had generally good luck printing in PLA. I bought some HIPs to use and tried printing something larger, and I’m seeing several possible issues and not sure what settings I should tweak.

Pictures of the print:
http://imgur.com/a/PaiCF

Link to model in question:
http://www.thingiverse.com/thing:1338488

I used Lulbot’s Cura v18.x on Windows 10 - I’m not sure on the point revision (I upgraded last night to 19.08 and printed off something smaller with few issues, but have not retried this model yet)

I used the basic eSUN HIPS profile in fast quality, then copied it over to expert. I don’t think I tweaked any other settings though. I was actually using eSUN brand HIPS. The default settings (from memory): print temp 240 / bed temp 110 / print speed 50 / infill 10 or 20% / layer height .25

From the pictures you can see layers separating, the corners lifted off the build plate, and the text that supposed to be in the base of the model is all melted illegibly (when it printed those first layers, you could see the text ok). The print took around 10 hours and I let it go overnight. In the morning when I got up, the item wasn’t stuck to the build plate, but it hadn’t moved (so I assume it came unstuck after the plate cooled off). I checked it a couple times before bed and I never saw the corners lifting.

So any advice on things to check/tweak before I try again?

On a print that size I would start by turning the fan off. That should help with the lifting and layer separation issues.

I run a TAZ, not a Mini so this next bit may be incorrect. The view of the bottom looks like you are either under extruding or the home Z height is too high. Make sure that you have measured the actual thickness of the filament and use that value. I find that a number of the 2.85mm filaments are actually closer to 2.81mm which can lead to small under extrusion issues.

I’ll try again with the fan off. I’ve checked the filament width in several places with dial calipers, most places it’s 2.89, I found one place that was 2.87. I double check the other settings to make sure they really were default/make sense, since I did go into “full settings” mode before printing.

Like I said, I was using esun HIPs (what lulzbot sells), used Lulzbot’s profiles, and calipered the filament. 110 bed 240 filament is what lulzbot’s profiles are set to, and that seems to agree with esun’s recommendations. Not sure what else to double check - that’s why I posted. I printed again, with no fan and got slightly better results, but there’s still corner lifting and layer separation, just not nearly as bad as on the first print. At this point I’m thinking the room we’ve go the printer in might be too cold and I should enclose the printer, I’m just working out what’s the best way to do that now.

I’ve not printed anything that large out of HIPS.
Printing large ABS pieces on my Taz, I’ve learned that enclosing the printer with foam board or just cardboard really helps. Just protecting it from drafts on one or two sides helps a lot as well. Uneven cooling during the print is what causes the lifting. The problem gets worse as your mass increases and as you get further away from the bed. Study your failed prints. They all contain lessons you can learn from. As geburges suggested, try lowering your fan and experiment with lower bed temps. For large objects, an enclosure to help keep things cozy while you are printing will help the most. I’ve spent hours planning an enclosure build…



Best regards,
PCH

If you decide to enclose the printer make sure to allow cool room air to the electronics in the side of the printer, the driver chips on the control board need cool air to work reliably. :sunglasses:

Can you successfully print small HIPS things? Every filament is a bit different, so I find I need to print a couple little test objects to dial things in before I do something larger. I use some Lulz HIPS as well, and find layer adhesion better with higher temps. I believe I usually run about 250.

If you decide to do an enclosure, this is a pretty easy build and helps a fair bit. http://www.thingiverse.com/thing:1258662

I don’t think I’ve ever done anything that large in HIPS, but I’ve seen it done without enclosures with good results. I only use the enclosure on ABS and Nylon at the moment.

For the bed, make sure the first layer is clean. It doesn’t take much to throw it off. Thoroughly clean the nozzle, I like to use a scotchbrite pad while it’s at print temps. As you have been using PLA, that can mess up the auto-level sensor. Give the leveling washers a wipe with the scotchbrite, and the PEI as well. Then clean both with rubbing alcohol. Watch the leveling to make sure the bed doesn’t move when the nozzle touches the washer the second time, when it’s going slowly.

Yup, that’s why I’m still working out how best to do it, instead of just covering the whole thing with the box the mini shipped in. :slight_smile:

Yup, made quite a few smaller things, only saw these issue with the larger build. I’ll try a higher temp.

Oh, I didn’t see that one while looking. I think I like that one.

That’s something we learned pretty quickly. PLA was really building up on the nozzle, and the bed was deflecting a small bit. Now I make sure I check the nozzle and really watch the leveling process and cancel if it deflects… But it hasn’t deflected since I’ve been extra cautious about cleaning.

I had similar problems when I first got my Mini.

With PLA the nozzle would not wipe properly and then the bed leveling would not work. It would press way too hard on the corners (especially the right front). No more PLA.

Then I tried HIP and it printed better but not great. Visible layer lines and such (not as bad as your example). The important thing was the leveling worked.

Then I tried ABS!!! Prints beautifully! Problem solved. I only print with ABS now. Way easier (and lazier) than figuring out temps and speeds, etc. If you try a spool of ABS You may never go back!

Chuck

I posted some comments about the nice improvements I got from HIPs from doing a couple simple calibrations here (it is the 5th reply)

https://forum.lulzbot.com/t/needing-cura-setting-suggestions/3306/8

I still need to post some pictures of the before and after installing the Y-axis stepper motor damper. It got rid of some ringing in my HIPS and ABS prints but I also tightened the belt so I can’t say for sure what did the trick but things are even better now. Not to mention nice and quiet!

Thanks! I’ll try those calibrations. I was just reading about dampeners this morning. I’ll look into that too.