Repeated Print Failures (Underextrusion)

[brentwerder 13]

Hey everyone,

I recently put up a post asking you guys what filament suppliers you guys like to use, and the support on that topic was amazing. I ordered some ColorFabb because of it, and now I'm waiting for it to get here.

Sadly, though, the last six prints I've tried have failed - and, for the record, each print was a 180mm x 180mm x 15mm tall model of the first step on the moon. Each one has had the same problem: Underextrusion. Which, I have to say, really, really sucks.

I've tried the Atomic method for clog removal (which helped a bit), turning up the heat, slowing the overall speed, and increasing the flow. Each one had helped a bit, and the last print I did (which failed ~20 minutes ago) started underextruding at 1 mm up. That print was the best out of all of them: I had increased the heat to 220C, and the first, second, and third layer printed fantastically. After that, the machine sped up, and it immediately stopped extruding. I think it might have been due to grinding, but I haven't checked that yet. That has been the case in the last five prints, so I'm sure this isn't any different.

Here's a list of specs so you guys can figure out what horrible mistake I've made quicker:

Ultimaker Original +

Bed Temp: 70C

Head Temp: 220C

Print speed: 80mm/s

Flow: 100%

Layer Height: 0.15mm

Acceleration: 2000

Filament Used: MakerGeeks - Maker Filament PLA

Thank you all for reading, and for your help with all these problems I've been having recently.

-Brent

[Labern 774]

Try upping your temp to 235deg.

220 could be a bit cold for 80mm/s, the faster you print and the higher layer height the hotter nozzle temp you need.

You can drop the bed temp to 60 though as 70 is quite high.

[brentwerder 13]

Got it - printing right now with a slightly downscaled model (so it prints a bit faster) and the higher nozzle temp. Bed is at 60C - that seems to be working. Fingers crossed!!

[brentwerder 13]

Okay, so the print is going okay, but there are a few problems going on that I can see - the tiny overhangs are looking terrible (because, I assume, of the high temperature), and the lettering on the side isn't looking too hot either. I had to manually change the acceleration value on the Ulticontroller (does anyone know how to change the accel. in Cura? I have yet to find a setting in there), and lowered the speed to 90. Occasionally there's a thump coming from the machine, which I've yet to figure out - could it be the travel? The travel speed is at 250mm/s, which is amazing for overhangs. There might be some loose screws that are causing that - I'll go ahead and retighten everything later. Any other suggestions for getting some better print quality?

[Labern 774]

you cant expect really good prints at that speed. if you want things to look really good you will need to print at 30 - 40mm/s, this will also mean you can print cooler and get really nice overhangs.

Acceleration cant be changed in cura.

Travel speed wont improve overhangs but it helps improve stringing.

[SandervG 1,521]

Do you have some pictures of your print? It would help us determine what can improve your print, which usually works better than trying to interpret a description.

Overhangs can also be improved by cooling. Do you have the metal fanshroud or the foldable one?

You say you reduced speed to 90, but from your specs up I read it was only 80mm/s?

The thumb could be a rod hitting a rod end cap. Not really a big deal, there are hacks available to prevent this.

[brentwerder 13]

Hello again everyone,

Thanks for the responses! I was able to get some pretty good quality with the Maker filament, but shortly after, I recieved my roll of ColorFabb which is printing right now with pretty good quality. Not fantastic - just pretty good.

To answer your questions, Sander, I have the metal fan shroud that came with the UMO+. It was running at 100% when the overhangs started drooping. Probably because I had the temperature ramped up so high. Also, I printed the second one at .15mm @100mm/s, and reduced it to 90mm/s during the print, which helped a lot. I'm sure I could have gotten much better results with it at, say, 50mm/s, but I had to turn in that print as a school project. Sidenote: my teacher thought it was the coolest book project she'd ever seen, and gave me an A+ on it

Right now, I'm printing the T-Rex Shower Head (thing:308335 if you're interested - hilarious idea) in ColorFabb. Here are some of the specs on it:

Material: Black ColorFabb PLA/PHA

Head Temp.: 215 (tried 210 but got a lot of underextrusion)

Layer Height: 0.2mm

Shell Thickness: 2.0mm

Speed: 40mm/s

Fill Density: 20%

Support: No

Bed Adhesion: Brim (20 lines)

[LePaul 321]

I'd like to see pictures of these prints to better evaluate what looks to be going wrong.

I have been printing with ColurFabb Black PLA/PHA and getting very good results. I have a UMO, not the + you have

I start my print at 220 and then bring it down to 210 once I have the brim printed/flowing good. I need print it down to 200 and find that 35-40 mm/sec yields very good results.