ABS prints with layer striation defects
Hi all,
I have been able to print Prusament PLA on my Mini with no problems but have been seeing striations/lines on my prints with Matterhacker ABS. My Mini is inside of an IKEA LACK enclosure and the enclosure temperature stays around 22-24C (my garage is very cold). So far I have tried:
1. Adjusting nozzle temperature between 220C to 255C
2. Adjusting print speeds for everything from 20mm/s to 50mm/s
3. Reducing flow rate by 2.5%
4. Adjusting fan speeds from 15% to 5%, or turning fans off
5. Rotating parts 45 degrees (on XY axis)
Nothing I've done has helped so far. Any advice is appreciated!
RE: ABS prints with layer striation defects
Your Boaty McBoatface looks a lot better, overall, than many I've seen on line and in real life.
Several months ago a user posted an issue with using ABS for it, mainly obvious lines where the decking meets the hull, and I offered to print one and compare, as we were both using the same type, color and brand of ABS at the time. Mine came out exactly like his.
Yours does show far more striations than ours did. (I can't find mine right now, otherwise I would post a photo).
Your wheelhouse sides look smooth, so I would think that rules out things like general inconsistent extrusion and loose belts.
My suggestion would have been to slow down your print speed, but you've already done it.
My one suggestion might be to try using a draft shield in addition to the enclosure. I have a temperature control in my enclosure and for a run of ABS prints I'll often set the enclosure control points in the high-mid 30s. 20s in the enclosure sounds very cool for ABS.
RE: ABS prints with layer striation defects
@jsw
Thanks for the tip about the draft shield, I will give that a try!
The wheelhouse has slightly less severe striations, it just doesn't show very well in the photos. But they are definitely present.
RE: ABS prints with layer striation defects
@jsw
Finally got around to trying the draft shield and unfortunately it didn't help. What equipment do you use for temperature control in your enclosure?
Printed several more Benchy's out of ABS and they all had the striation defect. Oddly enough, the striation patterns all occur at the exact same layer height in every ABS Benchy print. It is the Benchy file from Thingiverse. I tried a good ol' Netfabb repair before printing again but it didn't help either. I thought it might be a materials issue so I printed out the XYZ 20mm calibration cube from Thingiverse as a test and it didn't have as good of a surface finish as the PLA, but it didn't have bad striations like the Benchy's.
It might be the enclosure temperature is too low like you suggested, but it's confusing why the calibration cube would print so much better than the Benchy, unless that's only because the cube has vertical sides. I will need to try printing a variety models with different geometry and see if the striations are only happening with Benchy.
As a sanity check, I printed another Benchy out of Prusament blue PLA and it looked perfect to me, no striations. So it does not appear to be an issue with the printer belts as far as I can tell? I also checked the extrusion rates also and everything looks fine.
Pretty stumped!
RE: ABS prints with layer striation defects
I have the same problem with printing filaments other than Prusament.
Example of ABS and ASA:
RE: ABS prints with layer striation defects
ABS shrinks as a percentage alot more than most filaments. So the internal structure of your part when sliced will also have an effect on how much it shrinks and in what areas. Basically there will be those areas in other materials if you really really look but they will be worse in ABS. In fact you can still see them on the blue benchy you pictured. Have a search the for the famous 'Benchy Hull line' article on the prusa site. It will explain a lot of it.