First layer quality and MK3 technical specification
Hello,
having finished the calibration process as described in the manual I printed some test pieces and am now wondering whether the quality is o.k. or not. To keep it simple, I used the settings coming with the driver package (0.15 optimal MK3, PLA filament that came with the kit) and the Prusa logo on SD card. I modified the z-axis calibration (in attached photo top to down with a setting of -0.725 / -0.75 / -0.8).
In my opinion the first print isn't o.k. (maybe hard to see on the photo) because there are some gaps (tiny ones, but still gaps) between the different rows, the next one is better and the last one (that with -0.8) yielded a closed surface, but still some structure on it. If I compare those pieces with the printed parts for the printer where (certainly on a different PEI surface, obviously the structured one instead of the smooth one that comes with my kit) I notice for those parts a surface where no or very minor filament traces can be seen. Therefore I'd like to raise the question what would be a good surface quality of the first layer. I know, there are much more settings possible in Slic3r, but before I go for further fine tuning I'd like to get a better understanding of the goal. Maybe my assumption that the original setting are already set to the optimum is wrong. If the goal would be to get a smooth surface of the first layer, I found the following advices, especially for the first layer: slightly higher (around 5 degree) temperatures for bed an hot end and/or speed reduction.
That now brings my to the second part of my question: Is there somewhere a technical datasheet of the MK3 printer that states the maximum settings of each item, e.g. speed of movement, max temperature etc? Looking at the Pruse page I found some questions answered but not all, and unfortunately a little bit scattered around different topics.
Kind regards
Jürgen
Re: First layer quality and MK3 technical specification
That last (-0.800) print looks pretty good to me--I have to go to -1.250 to get that (Since I can't get an answer on that, I'm beginning to think I may have a wonky PINDA). The difference you're seeing vs. printed parts may have several reasons, one being filament color--the way light reflects off of gray vs. black or orange. Sometimes scraping a thumbnail across the surface can give a better indication of one print vs. another.
Number of layers may also have an affect; these are bottom layers vs. perimeter layers or top layers on the printed parts.
Have you printed anything other than single layer tests (like an actual object?)
That's "MISTER Old Fart" to you!
Re: First layer quality and MK3 technical specification
Hello Rufus,
those prints were basically the first ones after having asembled the kit. In the meanwhile I spent some hours in different areas to find out what a good print would be. Being new in this printing business it was a little bit hard to understand what makes a good print. At the end I followed an advice here in the forum und printed only one layer tests with different z-axis settings. I started with 25 µm steps form -650 to -850 and ended after a while with smaller steps at -795 µm. That yielded a closed back side of the print with the required thickness of 0.2 mm - and my thumbnail tells me only a very minor structured surface. So I guess the setting is now good enough to go on with some more parts.
I found an interesting test object (I think somewhere in Thingiverse) that gave me a good impression what are the limits.
Regarding PINDA: As far as I have understood it you probably need to lower your sensor a little bit. I did during assembly what have been suggested: Using the main part of a zip tie to set the hight (others are using credit cards). At the end the Pinda should be a little bit higher than the nozzle.
Kind regards
Jürgen
Re: First layer quality and MK3 technical specification
Yeeeeaaaah.... I spent the better part of 2 days adjusting that l'il sucker up & down with a caliper. Moving it any lower grabs the paper and pulls it across the print bed.
Been through this in another thread; no answers there either.
If those pics are your actual print (vs pics from Thingiverse, etc), then I think you're in good shape--unless I'm missing something (eminently possible).
That's "MISTER Old Fart" to you!