Troubleshooting fine pillars
I assembled my MK3 in March and was pretty happy with its printing, but around June started noticing more issues with its print.
My first layers seem pretty good (see attached photo with tim-m30's 60 mm circle).
See the "mini" all in one printer test here. This is using the filament Prusa ships with the printer (not amazing filament, not terrible).
Fine (thin) pillars have noticeable layer shifting.
I am not sure if the overhang test can be considered a failure - this print goes well beyond the 55% that is considered the max acceptable by the Prusa slicer's default setting.
Also not sure if I should expect the text to be rendering better.
Any thoughts about what I should do to improve print quality? Thank you.
RE: Troubleshooting fine pillars
Oh, ugh, the images are still rendering badly. Can this be fixed yet?
RE: Troubleshooting fine pillars
(so frustrating we cannot edit after a short period of time) sorry, I have a 3S, not a 3.
RE: Troubleshooting fine pillars
Oh, ugh, the images are still rendering badly. Can this be fixed yet?
At least you got the LINK TO : MEDIA FILE clicked before inserting them. I find using the minimum or medium thumbnail and LINK TO MEDIA the best option. Folk can then click the image and zoom in. Like so:
RE: Troubleshooting fine pillars
As for the test part text? Yours looks a bit stringy, but not really too bad. The text on my attempts doesn't look that great, either. But the features all turn out okay - thin gaps, sizes (except inner diameters) ... so not perfect. Though I have seen examples that were printed better. But not sure how much time to spend optimizing a test when most of the work isn't easily transferable to other parts.
RE: Troubleshooting fine pillars
ps: Most of the artifacts are print speed issues. Slowing down external perimeters will make a marked improvement in wall quality. Adding perimeters will help in a few places. And slowing top infill and reducing flow rates might help with text resolution (my print was suffering over extrusion from a filament that was >1.75 mm diameter).
RE: Troubleshooting fine pillars
Next time I will try that photo technique, Tim! Thanks.
I take your point about whether it's really worth shedding a lot of tears over a torture test rather than an actual piece one wants to produce.
I'd tried this test item because I felt I'd been having a lot of problems with fine areas and it seemed that my first-layer calibration wasn't fixing it. But given your comment, this morning I tried for a more real-life test, and re-printed a filament clip that had been printing well in the past, then had started printing very poorly.
It came out beautifully, so maybe all that first layer calibration I've done in the interim helped after all.
I'm printing the Prusa castle now to see how a more complex piece goes. Nine hours remaining but it's looking fairly good at the moment so .... fingers crossed.
The stringing doesn't bother me so much as it is very humid here at the moment. Most of our year is pretty dry (New England region) so it's a temporary issue.
I also appreciate your tips for improving quality on walls and resolution.
RE: Troubleshooting fine pillars
Oh, interesting. Those look like really nice points...
RE: Troubleshooting fine pillars
Having printed the castle, I think it came out fairly well, with the exception of a scar on the multi-sided tower top that may be the seam. I think I see the same seam on this print of the model, though not as bad.
As far as the original issue, I feel perhaps the quality of smaller crenellations could be better, but they could be worse. (50 cents to me for that terminology.)
In the last closer up photo, I'd cleaned off some stringing.
RE: Troubleshooting fine pillars
I just printed my first castle yesterday. I'd post my pictures for a comparison, but I'm away and won't have access to it for several days. But from memory, I think mine had noticeably less stringing. I did have the scar/seam/gash on the roof of the one large tower, and a smaller less obvious seam on a second, smaller tower. I was worried that it was something that happened in my printer, but it appears to be at least a common shared issue (sort of reassuring, I guess?). The tower in the bottom right of your second picture, the one with the narrow windows or arches separated by thin vertical "walls", had some issues printing those thin walls. They looked somewhat underextruded or uneven in mine, and one of the walls broke free entirely from the inner window perimeter. Those were the main issues I noticed, though, and overall I was very happy with the result. If I remember, I'll come back and post my pictures for comparison early next week.
RE: Troubleshooting fine pillars
Thanks! I'd really like to see yours!
I mentioned above that it's been really humid here, so I think that's the reason for the higher stringing - I did not have as much a couple months ago. But if it doesn't simmer down by the fall, I will need to do some troubleshooting.
RE: Troubleshooting fine pillars
The castle looks pretty good, though the walls show some axis meandering that can probably be tuned out by getting the belts a bit tighter. But the belt numbers on the LCD display are not very telling - so best to use other methods, like "just enough tension" the vertical walls of parts are clean and uniform.
A heat gun can help with spider webs, but caution needed to avoid a total meltdown. Quick passes of a hot air blast does wonders.
To be honest, there are some filaments that on my printer simply work better than others and don't seem to display any print issues. Yet other filament from the same manufacturer, but a different color, just doesn't do well regardless. Some aspects of this hobby are just frustrating ... lol.
RE: Troubleshooting fine pillars
I have been wondering about the belts. For the little it's worth, I'm at X = 265, Y = 285, and the X does feel noticeably tighter when pinching the bands together. I'll tighten up the Y a bit and try again. I'd wondered if it was the other way around, X too tight. This is where experience helps - I don't yet have a good feel for symptoms of common issues.
I just had to throw out some inexpensive white PLA that I just could not get to print successfully any more. Maybe it had absorbed too much moisture. On the other side, Fillamentum Extrafill in Rapunzel silver is gorgeous, always prints beautifully. This one is the Prusa generic that came with the kit, and I use it for OK but not astounding results. 🙂
RE: Troubleshooting fine pillars
Ignore the belt numbers on the display: they tell you you X axis has more drag (binding) than the Y axis. Less is better.
Belt tension, unless so tight it is warping the frame, does not increase drag (well, it increases motor bearing drag, but if that is a significant part of what's happening, then you have serious problems or an ultimately fine machine).
A 250 gram weight placed on the belt should deflect it about 6 mm (1/4 inch). That equates to about 8 pounds static tension. Belt is rated from 2 to 25 pounds; and the motor bearings rated for 11 pounds. 5 to 8 pounds is a good compromise. Set to 8, and it'll stretch out to 5 with time and wear.
After setting belt tension, especially if there is a significant change, a calibration is a good idea to recalibrate X and Y step multipliers.
RE: Troubleshooting fine pillars
Here are the pictures of the castle that I mentioned last week. Looking at the pictures, I think I had a lot more stringing than I'd initially thought/recalled.
