Should I persist with the MKS3+ ?  

RE: Should I persist with the MKS3+ ?

I had to lubricate my bearings.  I did not experience the scored rods from them, but I did have quality issues until I did it.  

Posted by: @crab

Having two sides to an issue is hardly in the realm of zealots. Bearings have failed in some customers MK3 machines. Fact. Misumi ships these bearings in oil and specifically instructs the user to remove the oil and grease the bearings. Fact. Packing oil is a lubricant and using it over grease makes the bearings much  smoother.. maybe this is a conscious decision. It's just not a manufacturer recommendation.  Even from the Support reply below, it is tipped in double negatives.. so there is a bit of hedging there. I think if I knew someone who was building a kit from scratch, I might tell them to grease the bearings.. just.. well.. it can't hurt ..  That said.. I think that Prusa would find a ton of bearing issues in their print farm if this was a big issue.. but no one knows what their maintenance process is.. maybe they grease their rods religiously. Hey.. maybe there is religion in everything.. 🙂  (reader will need to click on pic to view its content .. don't miss the two "not"s)

 

Posted by: @jsw

If you think that's amusing you should go look at one of the "bulge" threads, it has it's own religion, complete with followers

Another 'religious' item, with followers and detractors, has to do with the need, or lack of same, to re-lubricate the bearings prior to assembly.  If the followers are to believed, you would think that most of our machines should have died and gone to the underworld by now.  😉

 

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RE: Should I persist with the MKS3+ ?

Chuck,  I'm planning  a third printer build this fall and I hope you finish your Voron build and testing before I make the next purchase.  Of a course we all want to hear about your option of the product.

RE: Should I persist with the MKS3+ ?

Posted by: @zbigniew-trzepizur

Amusing as this thread is, I find it a great study of several sociological phenomena 😊 

It certainly is! Been fascinating to watch how this issue is dismissed as complete user error / limits of fdm 3d printing / conspiracy theory (??), when there's plenty of people who are also reporting the same issue.

I can see you guys are passionate about the mk3s+ , but need to be careful of that blinding you to its issues.

Here's a good comparison with another mk3s+ and an ender s1: https://imgur.com/a/tTv5ey1  

The top two are two different mk3s+'s and the other is an ender s1. You can see a clear difference in the prints there. Same filament type and temps etc.

RE: Should I persist with the MKS3+ ?

I guess I've never experienced the problem as most of my prints have come out extremely well.

Your prints look good, but the surface issue is clearly visible there in the photos you've posted (particularly the second). You've also got some issues there on the first layer with the uneven lines. So while the dimensional accuracy etc looks good, it's far from perfect. 

RE: Should I persist with the MKS3+ ?

I’ve built and printed with 3 3+ kits. Perfect prints except when I messed up. Printer number 3 Bondtech 😁

RE: Should I persist with the MKS3+ ?

Posted by: @dave-f

[...] I can see you guys are passionate about the mk3s+ , but need to be careful of that blinding you to its issues.

You're getting push (bite) back because many of us have been down this path before. Lest anybody buy into the "602 only affects Prusas", I give you this tidbit from the Voron forums:

Yes, 602 is a thing. There are a lot of issues that are attributed to 602 that are in reality other issues. Bowden extruders seem less susceptible to the effect, possibly due to more slop in the feed. There was also an interesting YouTube video (link unfortunately lost) that pointed the finger at the E3D extruder -- deviations in the walls due to deformation of the filament by the direct drive gears IIRC -- as a contributing factor. In short: Printers with a high degree of precision show the effect more because they can show the effect more. If everything is a bit off and wobby, a large vertical wall looks pretty good.

602 is also very subjective. I was convinced I was getting perfect prints, but print a wall in a shiny filament like silver and shine a light from above and you'll see it. Once seen, it cannot be unseen. However, I am not printing in silver frequently, and don't go out of my way to light things in a manner that is well known in photography circles for producing poor results. There's a very good YouTube video (link also lost, but I'm looking for it) in which the tester spent a month doing dozens if not hundreds of prints in order to isolate the problem. His ultimate conclusion was that there are a few basic things you can do to improve your prints, but that in the end, it really wasn't that big of a deal and a waste of time worrying about. 

So far as your pictures, your close ups of silver prints in bad lighting do look about right. Your last however looks beyond bad, with all sorts of deformations that look nothing like typical wall variation associated with 602. If you're going to do a meaningful comparison, please print the same part with the same filament using similar settings (particularly perimeter speeds) in the same lighting (stacking is good). 

602 exists to some degree with any FFF printer. If it truly bothers you, by all means use another printer. Don't fool yourself into thinking that someone can't go out of their way to light prints in a way that the results look like crap when magnified 400X though. If you want to avoid the issue, resin may be the way to go.

Meanwhile, the Mk3 can produce very good prints. I always recommend simply slowing down to ensure even flow, then tweaking settings.

RE: Should I persist with the MKS3+ ?

Ah, I found the link to the testing video. tl;dr starts here.

In short, if it bugs you that much, try another printer. Meanwhile, plenty of users get very good results with Prusas for their prints and get tired of hearing how they can't.

RE: Should I persist with the MKS3+ ?

Send me the printer and I’ll send you a czech 

RE:

Posted by: @bobstro

In short, if it bugs you that much, try another printer. Meanwhile, plenty of users get very good results with Prusas for their prints and get tired of hearing how they can't.

Yeah that's what I ended up doing in the end. (Side-graded?) to an Ender S1. While admittedly the build QC out of the box wasn't a good as the Prusa (lots of things loose and out of whack), eventually after a partial rebuild was able to get it consistently producing some great prints.

Here's the whistle and a benchy (both from the Prusa SD card and using included Prusa filament) comparisons:

https://imgur.com/a/n1kSmPs

https://imgur.com/a/sWDjl3b

MK3S+ on the right in both examples

I think in isolation most people don't notice the issue on these types of models, which is why I think most people say 'my mk3s does great prints, you must be doing something wrong'. But when even those who say that then post a example you can clearly see issue 602 issues in what they're seeing as great (such as the posts a couple back).

Even when you look at the whistle example that Prusa have on printables  https://www.printables.com/model/65-whistle   , it clearly shows it being close to what came out of my mk3s. But again in isolation most would consider it fairly acceptable.

I think I'll end up settling with a setup of a Prusa MINI+ and the Ender S1 for larger prints. As is still in total less cost than a single mk3s+ and the mini has excellent surface quality and no doubt will beat out the S1 for reliability, just hard to get around the size limitations.

All my original question was trying to ask is, if I persisted could I somehow remove the issue 602 effects so they looked like other printers. But unfortunately the answer seemed to be no.

RE: Should I persist with the MKS3+ ?

Posted by: @dave-f

[...] All my original question was trying to ask is, if I persisted could I somehow remove the issue 602 effects so they looked like other printers. But unfortunately the answer seemed to be no.

As with all things subjective, use what you prefer and can get acceptable results with. 

RE: Should I persist with the MKS3+ ?

My Mk3s benchies look on par with your left examples. I do have the comparison to another printer, a Voron 0.1. It prints better quality than both Prusa and your Ender example, however it is not great for PLA as the part cooling is not the strongest. But then, I have the Prusa for PLA stuff.

The Ender is probably a perfectly fine printer if you take care to dial it in and possibly upgrade this or that. However, every printer with this plastic wheel rails has inferior longetivity as those degrade which leads to wiggle room, unless replaced. 

RE: Should I persist with the MKS3+ ?

I think that depends on the definition of perfect.  Some ender-3s are garbage.  I own 2, and one is only worth recycling.  

Posted by: @thejiral

My Mk3s benchies look on par with your left examples. I do have the comparison to another printer, a Voron 0.1. It prints better quality than both Prusa and your Ender example, however it is not great for PLA as the part cooling is not the strongest. But then, I have the Prusa for PLA stuff.

The Ender is probably a perfectly fine printer if you take care to dial it in and possibly upgrade this or that. However, every printer with this plastic wheel rails has inferior longetivity as those degrade which leads to wiggle room, unless replaced. 

RE: Should I persist with the MKS3+ ?

I don't own one, so I can just repeat hearsay and that hearsay is that they are cutting corners at QC. So it is a big gambling. Chances are that you are getting something useful for cheap but you can also end up with garbage. In any case, they are not designed for high durability in mind, even in the best of cases, without heavy modding. 

RE:

@Thejiral .. 100% agree.. even as a retired Engineer, I picked a Prusa for its reliability and ease of use .. I wanted to print stuff.. There are imperfections in the surface, but I think Prusa's continual evolution from the MK3's use in its print farm has shaken out most bugs so it is a 'pretty good' and more reliable product that most of the others. It's like espresso machines.. you can pay 5x the price for 10% improvement in quality.

RE: Should I persist with the MKS3+ ?

Perfect surfaces are unachievable with FDM printing to begin with. There are however indeed differences in artefacts and imperfections. They seem to differ quite a bit from individual printer to printer and possibly even over time and are hard to tackle, probably a combination of various factors which are rather illusive or can be only adressed with radically changing the design. 

The only thing the Mk3s is really missing in my opinion is something like Input shaper, which is not possible with the current electronic layout and firmware but should be integrated in one way or another in the next iteration I think. It really kills ghosting even at higher printing speeds (yes it does also leave some very minor artefacts which one can identify if looking just hard enough but you can always find something). This needs some redesign but not a radically more expensive design. 

If you want to have perfect surfaces and tiny details (and are ready to compromise on the material specs of your prints, like toughness or impact resistence) get a resin printer. 

RE: Should I persist with the MKS3+ ?

Posted by: @thejiral

Perfect surfaces are unachievable with FDM printing

That is what sandpaper is for.  

RE: Should I persist with the MKS3+ ?

Perfect surfaces are unachievable with FDM printing to begin with. There are however indeed differences in artefacts and imperfections.

Yes of course. I was never expecting perfect. I just expected similar or better surface quality than my much cheaper Bowen style machines from the mk3s.

For now I’ve been able to achieve that with the ender s1, and will move to the bambu lab x1 once it’s here in a few months. 

Obviously the mk3s is excellent when it comes to reliability, but is clear to me now from looking at the alternatives there’s better options if chasing print quality.

RE: Should I persist with the MKS3+ ?

If the MK3 series Prusa printer fails to produce prints that are cosmetically or dimensionally equal to or superior to those printed on any of the other similar class machines, something is wrong and needs to be corrected.

As has been stated several times, filament-based 3d printing will always show SOME surface texture unless post-processed, however, the surfaces of prints should be reasonably smooth (see examples below) and visually appealing.

If a new machine fails to produce such prints, support needs to be contacted on the issue.  If a support agent says that an obviously inferior print is 'acceptable', the issue needs to be escalated.

RE: Should I persist with the MKS3+ ?

Posted by: @jsw

If the MK3 series Prusa printer fails to produce prints that are cosmetically or dimensionally equal to or superior to those printed on any of the other similar class machines, something is wrong and needs to be corrected.

it depends on expectations.  Rarely are they class smooth, but I have made pretty good quality prints that are marketable.  

RE: Should I persist with the MKS3+ ?

Indeed. The magic word is post-processing. With resin printing, post-processing is even hard-coded into the printing process. FDM is much easier in this regard. There post-processing can yield great results but is often not even necessary at all.