Prusa summer update  

Re: Prusa summer update

Bobstro,

OK. will do.

I just checked and I do have some "fresh" unopened PRUSA Silver PLA. I received this last Sept/October with my 2nd MK2S. The date on the box is 8/28/2017.

I just opened the package and placed it in my drying oven at work. This is standard practice for me - When I use a new spool of filament I place it in my drying oven for a minimum of 48 hours before I use it. If I don't plan on printing something for a few days I unload it and stick it back into my drying oven until I'm ready to use it. This is something that I started doing when I had my "TIKO 3D" printer - the PLA they shipped with was terrible unless you dried it.

So I'll print on Monday the 2 cubes are work, and then bring the spool of silver home and print the same cube that evening.

Re: Prusa summer update

Looking forward to seeing your results. Thanks!

Re: Prusa summer update

well... the 2 MK2S test cubes are done.

You'll have to wait until tonight when I get home and do the test cube on my MK3

So far, I'm not surprised at the results...

Re: Prusa summer update

OK. I have run the following calibration cube (20mm) on all 3 printers (2 MK2S, 1 MK3 - all pre-built).
Fresh install of Slic3r PE 1.40.1+ on Windows 10 64 bit, fully updated

Print Settings
MK2S
- 0.20mm Normal
- 0.20mm Linear Advance
MK3
- 0.20 FAST

Changes made to all printers
- Perimeters 1
- Top Layers 0
- Infill 0

Filament Settings = Default Prusa PLA
- Extruder (215/210)
- Bed (60/60)

The MK2S are running FW: 3.1.0. (2 cubes printer per printer)
The MK3 was running FW: 3.2.1 (1 cube printed) then updated to 3.3.1 (1 cube printed)
Total cube = 6

I labeled all 6 cubes then put them in a pile and mixed them up. Then, without looking at their labels, I arranged them. It is difficult to try to get a good illumination for all 6 cubes so I moved the light about and try to take representative photos. I annotated the photos with the cube numbers for reference. If you want a specific cube re-photographed let me know.

Re: Prusa summer update

Here are some more photos

While it may not look like it, but every cube has some type of "lines" when the light hits them just right. Some are more pronounced then others.

Re: Prusa summer update

I hope C3 was the mk3 with the latest firmware update. I think that looks the best in the last set of photos.

Edit: maybe C6 looks better comparing both top and bottom photos.

Thanks for taking the time to print and post by the way!

Re: Prusa summer update

Is this a guessing game? Do we have to support you on Patreon or something to get the results? 😆

Re: Prusa summer update

Is this a guessing game? Do we have to support you on Patreon or something to get the results? 😆

If I've understood correctly, some number of cubes are printed on a Mk3, which we all know has extrusion issues which make prints nigh-on unusable. Some number of other prints are from a pair of Mk2s, which has legendary print quality and none of the extrusion issue plaguing the Mk3. Or, if you will, and objective test of quality. I love it.

I'm going to go with 1, 3 and 4 are one Mk2s, 6 is the other, 2 and 5 the Mk3. I'll hold off on my reasoning until the end. But then, I see the 2nd set of photos and my logic goes out the window.

If nothing else, it's good to see a mix in the same pics. Perhaps we can agree that crappy lighting can make any printer look bad. There are some differences, but we're zoomed in and most appear to be in small fractions of a mm. This is perfect. Thanks, Bytor!

Now if JP winds up making prints look decent in this light, maybe someone will give him some overdue credit.

Re: Prusa summer update

Thanks Bytor, that's really interesting !

The important fact is that none of them is free of "inconsistent extrusion" contrary to what we can hear about MK2.

And the photo angle is really important to make it appears, C3 and C6 seems perfect on some photos but are not.

I'll try the same comparison with a Raise 3D N2+ I have at work.

Re: Prusa summer update

If nothing else, it's good to see a mix in the same pics. Perhaps we can agree that crappy lighting can make any printer look bad. There are some differences, but we're zoomed in and most appear to be in small fractions of a mm. This is perfect. Thanks, Bytor!

Well, I certainly can agree. Indeed that is what we found ages ago when doing our own comparison tests.

But even so, tell which is which please 👿

Re: Prusa summer update

Is this a guessing game? Do we have to support you on Patreon or something to get the results? 😆

Damn... why didn't I think of that...

I'll release the order tonight when I get home.

Re: Prusa summer update

One thing I didn't mention and I did it on purpose because I wanted to see what people commented about the photos.

In some photos certain blocks look worse/better than neighboring blocks. Well, you can manipulate how bad or good they look by changing the angle of the light and/or the distance of the light from the block.

"IF" I played around with the light with the blocks individually I could get them to look pretty much any of the other blocks.

Now... If I don't shine a light on them and I just look at them, from most angles and normal lighting, they all look fine. If I run the tip of my fingernail up/down their sides they all feel the same (note, I have a calibrated fingernail for this type of analytical analysis).

As I said earlier this year when I first started seeing people complain about the print quality of the MK3 over the MK2S... to me, they print the same.
I'm not saying the MK3 is perfect, or the MK2S either. They have "real" issues and not "forced" issues. I feel that JP and his team have been making improvements via firmware and component modifications to help reduce those real issues.

Re: Prusa summer update

[...] I'll release the order tonight when I get home.
Noo! Give it a week at least. Give everyone a chance to weigh in. There's supposed to be an obvious quality difference after all.

Thanks again for this, Bytor. I'd certainly appreciate seeing similar objective comparisons with results off other printers. Consistency between pictures is the key. Good stuff.

Re: Prusa summer update

[...] As I said earlier this year when I first started seeing people complain about the print quality of the MK3 over the MK2S... to me, they print the same.
I'm not saying the MK3 is perfect, or the MK2S either. They have "real" issues and not "forced" issues. I feel that JP and his team have been making improvements via firmware and component modifications to help reduce those real issues.

I think you're absolutely right. If I compare my little 20mm cube printed in April against the one printed recently, there's a marked improvement in quality. Part of that may be due to me getting smarter, but more is due to incremental tweaks to the Slic3r software, firmware and gcode tweaks issued by Prusa & team. It's not perfect, and in the right light the issue can still be seen, so a lot of people discount Prusa's efforts completely.

Re: Prusa summer update

OK... I'll give it a couple days before I release the order/printers... just to torment everyone 😈

One of the other issues people have complained about is the moire pattern. It's another "issue" that is being blamed on the MK3 that wasn't there on the MK2/S... thing is, I've had it prints from the MK2S as well as the MK3.

I wonder how many people that are complaining about these "issues" that are on the MK3 vs the MK2/S actually have both systems? How many have actually printed the same object at the same time on both (using the same slicer/settings)?

While I'm still a newbie at 3D printing, I've done enough Quality management, Root Cause, Six Sigma (name your flavor of the year) to say that people are making a lot more out of this than it needs to be (IMHO).

Overall this reminds me of one of my Quality Improvement Managers (QIM) at a job about 20 years ago. We had a DCS (Distributed Control System) that controlled the whole production process of a chemical. One day the QIM was in the control room looking over the shoulder of the operator. The QIM got all worked up over what he saw and called a meeting saying that we were making terrible product on one of the lines based on what he saw in the control room. The QIM wanted hundreds of thousands of dollars to get us some new, more efficient/consistent pumps. When asked why and the justification he mentioned the erratic flow rates of the chemicals that he witnessed on the DCS.

After an investigation by me and a couple others we reported back to Management that no spending was necessary to fix the issue. The issue: The operator had 3 screens up on 1 display with the chemical flow rates for one part of the process. One screen had almost a straight line for flow, the next screen had a slight sine wave line flow and the 3rd screen had these big peaks/valleys for low.

What the QIM didn't realize was that the scale of all 3 screens were all set differently - something the operators were used to seeing and changing as necessary. The QIM didn't even bother to look before jumping to conclusions about there being a serious issue, when it was nothing.

Re: Prusa summer update

OK... Here's the order:

C1 = 2nd MK2S with Linear Advance profile
C2 = 1st MK2S with Normal profile
C3 = MK3 with 3.2.1-576 firmware
C4 = 1st MK2S with Linear Advance profile
C5 = 2nd MK2S with Normal profile
C6 = MK3 with 3.3.1 firmware

Re: Prusa summer update

OK... Here's the order:
Thanks so much for posting this. Next time I see somebody wavering about buying the Mk3 because of "all the extrusion issues", I'll point them to this thread. Good stuff.

Re: Prusa summer update

I hope C3 was the mk3 with the latest firmware update. I think that looks the best in the last set of photos.

Edit: maybe C6 looks better comparing both top and bottom photos.

Thanks for taking the time to print and post by the way!

OK... Here's the order:

C1 = 2nd MK2S with Linear Advance profile
C2 = 1st MK2S with Normal profile
C3 = MK3 with 3.2.1-576 firmware
C4 = 1st MK2S with Linear Advance profile
C5 = 2nd MK2S with Normal profile
C6 = MK3 with 3.3.1 firmware

Thanks Bytor! I feel more confident that I need to update my firmware to the latest version now. I always wait a little while at least until it's sorted.

Re: Prusa summer update

Awesome thread, thanks for doing this! I'm honestly surprised that no one has tried to attack you and discredit this somehow. This should be a sticky.