Bottom surface quality + runs  

RE: Bottom surface quality + runs

So I did another print and this time looking at the model on the slicer I am noticing the "Runs" are also on the sliced view within Prusa Slicer. The bottom quality still hasn't changed, but to be expected. 

RE: Bottom surface quality + runs

What you call runs are seams, this article will give you some tips on that  https://help.prusa3d.com/article/seam-position_151069 .

The bottom is the result of poor adhesion, you might want to check your support and raft settings, it looks like you're allowing too much space between the print and the raft/supports.  Also, you can't expect a speed setting to give you the best quality.  The sidewalls of the spaceship look reasonably OK so your printer seems to be functional.  Printing a Marvin or a Benchy from gcode supplied by Prusa for the mini will give you, and us confirmation of the ability of the printer to provide good prints.  Those are my first prints with a new printer since they're known quantities and can identify flaws with the printer components or assembly.  Once you know the printer is in good shape we have a better chance of dealing with model or slicer issues.

Cheers

-Bob

RE: Bottom surface quality + runs

Bob, this was very helpful thank you for the reply! I've attached some photos of my Benchy tests. 

Images with smokestack: .15mm STRUCTURAL with Hatchbox PLA, no supports, 15% infill and Brim added
Images without smokestack (I accidentally snapped it off) 0.20mm SPEED with Hatchbox PLA, no supports, 15% infill and brim added

Thank you again for the help! Any pointers on how to further increase the quality is much appreciated. 

RE: Bottom surface quality + runs

RE:

Your Benchies look reasonably good though you do have some artifacts.  Those artifacts could be extrusion, temperature, belt tension, loose screws, slicer choices, or a quirk of the filament.

Do you have the SD card that comes with the printer?  Prusa supplies Gcode on them that have been optimally sliced for your printer.  By printing with Prusa's gcode we know that there are no slicer issues messing with your print.  I understand that this printer is second hand so you probably didn't get the filament that was shipped with it, but I'm hoping you got the SD card with the pre-sliced demo gcode.  Prusa printers usually come with a role of Prusament Galaxy Silver PLA.  In the old days you'd get a full 2kg roll, today you get enough for a couple of prints.   If you have the patience buy a roll of Prusament PLA and print with Prusa pre-sliced gcode, if you don't have the SD card you can download a zip bundle for your printer here: https://help.prusa3d.com/article/sample-g-codes_529630

Right now there are many variables floating about so it makes it hard to give you suggestions, pre-sliced Prusa gcode and Prusament PLA will insure that any artifacts that show up are related to the printer and/or its assembly.  If you get an artifact free print from pre-sliced Prusa gcode and Prusament PLA then you'll know that it's either your slicer settings or the filament or perhaps both.

Oh, and ONLY use gcode from Prusa themselves.  Nasty people can insert codes into gcode that can mess up your printer, Prusa wants you to be successful so they won't do that.

Cheers

-Bob

If you don't want to buy Prusament then you might be OK with Hatchbox, I've used a fair amount of Hatchbox PLA and I like it. 

RE: Bottom surface quality + runs

Hey Bob, finally got around to printing the Prusa linked benchy GCode.  What do you think would be reasonable to target next? 

Note I did re-adjust my first layer height which I think might need more adjusting as it seems maybe a bit worse now. Is there a way to use a feeler gauge for this step to get closer?

Side note: I did buy my Prusa secondhand, and the listing was for a Mini+ but how do I verify this is a mini+ and not a mini? 

RE: Bottom surface quality + runs

You still have artifacts, so now we know for certain it isn't your gcode, so something in the physical build of the printer is causing you a problem.  Here is one of my benchies, I can't say for certain if this was printed on my mini, but I looked at all my benchies and they're pretty much all the same.

Based on your first layer calibration, I'd say that looks pretty good, you may be a touch too low based on the ridges on either side of the rectangle, the gap in the bottom of your benchy is probably more an issue of cleanliness than z-offset.

It looks more like uneven extrusion, some of your layers look like over extrusion, some look like under extrusion.  I may be off base here, as these kinds of artifacts could be the result of loose belts also or loose parts.  Check your belt tension and the screws on your gantry. 

You say this is new to you, do you know how old it is and how many hours of prints there are on it?  Take a look at this site https://help.prusa3d.com/article/regular-maintenance-mini_133222 maybe this printer has had it's maintenance neglected.

Cheers

-Bob

RE: Bottom surface quality + runs

Thanks for sharing this Bob,

I went through and cleaned the rods as well as the fans and tried to clean off the nozzle as well. My hot end assembly is a bit dirty still (might need to be replaced). I am finding I am still getting issues with skipped layers and was wondering what you would approach first? I saw this video but I was not sure if this in-depth of a step should be taken first. 

Thanks!

RE: Bottom surface quality + runs

Finally, Success! My heatblock and nozzle were horribly dirty from the past user so I went ahead and swapped those for new ones, fired up the printer and found the issue actually got worse. I was going back through trying to understand what else it could be and remembered the PTFE tube had a little bit of discoloration on it, so I took the old one out and swapped with a new one and set the printer up with a benchy. Overall I am very happy with the results and I think with a little fine tuning it could be even better. Thanks alot for all of your help Bob!