Print quality issues at the seam when printing a cylinder
I successfully printed the following model:
https://www.printables.com/model/3710-collapsing-pirate-sword-print-in-place
But noticed what I thought was a fairly wide gap along the seams of the cylinder, and upon closer inspection noticed poor adhesion along these seam line on both thicker and thinner pieces (see below). It didn't take long for some of the cylinders to crack along these seams.
I came across the following set of settings from another thread:
https://help.prusa3d.com/article/seam-position_151069
and I'm wondering if this is an issue where I need to specify a negative "seam gap distance"? Possibly also randomize the start location of the seam?
Curious if others feel this is a tunable issue in the settings, of if something else is going on. This print was done on PLA with all default settings.
Thanks for sharing any thoughts or advice. 
Best Answer by JoanTabb:
Hi Mantrout,
If you select all printers, in the configuration filament window, there is a 'Generic PLA Silk*' option....
however it has an asterisk (*) next to it, indicating that it is not compatible with all printers, which is probably why you can't find it when you select Prusa Mini printer...
Have you considered trying the
Rosa3DPLA Silk profile, to see if it is any help?
regards Joan
RE: Print quality issues at the seam when printing a cylinder
You want to make sure there are no clogs and the hot end it put together correctly.
I'd suggest first doing a belt tension calibration:
https://help.prusa3d.com/article/adjusting-belt-tension-mini-mini_157324
Then do a linear advance calibration:
https://www.printables.com/model/90640-prusa-mini-linear-advance-for-prusament-pla-and-pe
The mini does not have an accelerometer so the settings are open loop and seem to vary machine to machine.
Then try some of the other seam settings. You can make improvements, but they may still not be great.
Regards,
Mark
RE: Print quality issues at the seam when printing a cylinder
From the looks of it, this looks like silk PLA. Are you using the Generic Silk profile, to make sure linear and pressure advance are set correctly? In any case, in my hands, silk PLA yields much more visible seams than regular PLA but I never bothered tuning it, I don't use it enough.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Print quality issues at the seam when printing a cylinder
Thanks for the pointer.
It is specifically this filament: https://www.amazon.com/dp/B0CP72P9PS
Which on the side of the spool is listed as "PLA+" so I've been using the "generic PLA" profile in Prusa Slicer. When I go read the product description on Amazon, it does say "silk" in the title, so now I'm a little confused.... I'll swap profiles and see if that makes a difference. Nice catch!
I'll re-verify the belt tension, but did go through that process maybe half a dozen prints ago. Will take a look at the linear advance calibration.
Thanks!
RE: Print quality issues at the seam when printing a cylinder
I wasn't able to find anything looking like a "generic Silk" filament profile, would it go by another name in prusaslicer?
RE: Print quality issues at the seam when printing a cylinder
Hi Mantrout,
If you select all printers, in the configuration filament window, there is a 'Generic PLA Silk*' option....
however it has an asterisk (*) next to it, indicating that it is not compatible with all printers, which is probably why you can't find it when you select Prusa Mini printer...
Have you considered trying the
Rosa3DPLA Silk profile, to see if it is any help?
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Print quality issues at the seam when printing a cylinder
Thanks all for the suggestions! I totally missed the ROSA PLA Silk profile.
So, looked into all the suggestions, I did re-calibrate my belts, which were a bit loos (wonder if they stretched a bit after initial build, but doesn't seem like a lot of load on them), I did the LA cal as well but the printer defaults seemed to be about right in this case. And then I tried the silk profile which I missed (along with a random seam patter). Although the random seam alignment is ugly as predicted, the seams look much tighter! I may print one more aligned just to see but it does look much improved (no holes along the seams).
Thanks all for the suggestions! I feel like I learned a lot and found some new tricks for troubleshooting in the future. I'll have to figure out how to mark the question answered.
I did re-calibrate my belts, which were a bit loos (wonder if they stretched a bit after initial build, but doesn't seem like a lot of load on them),
It's the reverse. The pressure from the belts together with flexing and vibration from printing have coaxed everything into place and the printer is running-in. No two users build identically but after a few weeks and a maintenance session the printer should be pretty good.
https://help.prusa3d.com/en/article/regular-maintenance-mini_133222
Cheerio,