Thoughts on Prusa MK4 and MMU3

Positive: easy swappable nozzles.

But, the nozzle is now the main calibration tool. Since my MSK3+ always drools a little with all types and brands of filament, I honestly don’t see how that will ever work properly.

And what if the bed is not so even, like mine. It’s still under warranty as a preassembled model, so I am not messing with the parts. No more live adjust z would be a disaster for me, even though the SuperPinda measures 49 points.

I can’t wait to see reviews on the MMU3 though.

The Mk4 has a different hotend, and I’d expect a purge line before leveling would address any oozing problems. At least, the early reports on the XL have not turned up a problem with the auto z-offset. On the contrary, the few reports I’ve seen have specifically praised that capability.

Despite the re-working of the OS, I’m skeptical that the ability to do a live z-offset has been removed from the firmware. It’s just not (so far) needed.

Given the problems with your printer, I’d consider pushing Prusa support for an Mk4 upgrade kit.


Thanks. I am gathering evidence once more, as problems slowly are getting worse again. It’s throwing blobs again, and currently having to do a first level calibration every couple of days now. Same problems as I had like next time. The purge line never helps, as all brands of filament ooze. I also never print too hot either, I stay within the boundaries set by the brands.

Maybe you’ve checked this, but my ender 3 pro was oozing up the kazoo about a year ago. I played with temps to no avail then noticed occasionally my hot end cooling fan chattered when starting on a cold machine. I replace the cooling fan and oozing stopped.

Thanks. Their new firmware made it better, as they said it addressed this. A known problem, apparently. Since I had 2 printers before this one, used the same brands at the same temps, it’s not either which causes the problem, but the printer is.

I can also add that the left front always detaches during a larger print. I rarely print large objects, as I print miniatures only. Makes me think the bed is warped. I know the Nylock option might fix that, but since the printer is under warranty, I can’t do that, or my warranty is void.

Plus, I think my new SuperPinda is already failing again too. Every couple of prints, it forgets where to start printing, just like last time when it started to fail. A first layer calibration fixes it for now, just like it did back then. I take pics to gather evidence. Once it goes totally off, I will run the test and gather the numbers for their helpdesk. I gather plenty of evidence, as I noticed last time by the way it was handled, that I need to.

Anyway, after Prusa fixed it, it printed better than when I bought it, but that doesn’t last long, does it!

I had this printer for 9 months and I have 2 months of acceptable print quality without too much hassle, 3.5 months out for repairs, and 3.5 months of constant struggle. I bought it 9 months ago to finish one of both big print projects for my blog, and have not succeeded to finish even one of both off!

Some of my readers even completely scrapped their plan to buy a 3D printer because of all the print issues I have. 2 previous printers were killed because of regular blackouts. New electricity here, designed by me and installed by hub. Officially checked and approved. But I live in a farm community where farmers clean their stables, forget their fuse boxes and spray water on them to cause blackouts, according to the provider. I put the Prusa on a battery, lesson learned after my second printer died.

I love 3D printing so much, being disabled and at home almost 24/7, it makes me cry that I paid so much and it’s so bad.

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Smart move to use a battery (UPS?) for your printer! I guess you have some surge protectors as well, to protect you from those crazy farmers, especially on circuits with sensitive electronics.

Belgian electricity laws are very strict, so the entire system is protected in 4 layers before it gets to any plug or light switch in the house to start with. We have 3 APC batteries (was the best I could find in Belgium) and oversurge protectors here too for our devices.

The indoors electricity is designed by me in 2016, hub had to install it due to my disability, and it was legally checked and approved before it got officially connected to the power grid. I made it even better than what the law states as minimal requirements. Most people don’t do that, as it costs extra. I have done that 3 times in previous houses and never regretted it once. I was even able to install each net completely myself and as a woman, I am pretty proud of that. Our house before this one had electricity done by the builder and it was a perfect example of cutting costs and not being able to switch several devices on in one go, or being in the complete dark when a fuse popped, bleh.

I have seen the provider remove a molten fuse on their tag sealed main fuse box in my house because of the spray happy farmers, lol. I saved a pic, it was this bad!

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Scary :grimacing:

I didn’t know you live in Belgium. It feels like English is your native language.

I wish I had known more about electrical circuits when we had our house built. I realize now that we could use a 20A circuit (120VAC) in our office. At 15A, I think we are close to the limit with five computers, a laser printer, and a 3D printer all on one branch circuit. I know we are close to the limit because the lights flicker a bit when the 3D printer bed is heating up or when the laser printer is running.

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Aww, thanks! I’m Dutch, lol. I have a proper Schwartzenegger style accent :rofl: Most Dutch Belgians over 49 speak 4 languages, as we have 3 languages in our small country. Under 49, they started dubbing movies and TV, so that skill has diminished.

I have 40A, each fuse has max 8 plugs, most devices / tools / appliances like a washer or dryer are on a single plug only fuse. Our fuse box covers almost the entire alphabet on fuses. Wet / dry areas are separated. This is actually the minimum obligated standard according to the laws here for new setups.

I am lucky to have a 3x220V system, as only old houses here got one easily back in the day, a real luxury to have. All lights are on 2 fuses with plugs, so you are never in the dark long, within easy orientation reach of a light switch on another fuse and at far less risk of going dark without any devices possibly causing it.

Much better than the old system, which was disapproved, as all houses on sale need a legal check. 30 plugs on one 10A fuse, rofl, some wires held together by wooden wash pins … :joy: :crazy_face:

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Fuses or breakers?

In the U.S. we tend to have more branch circuits, but each with lower current capacity. I guess this is to reduce the chance of short circuit caused fires by limiting the max number of kW, generally to 120VAC x 12A continuous = 1.44kW, before the breaker will trip. The regulations are a bit complicated, and require downrating the max current due to the breaker possibly running in a hot breaker panel to begin with.

Anyway, it sounds like you are in good shape to have a nice printer farm :slight_smile:

Given the trouble I have had so far with only one printer, nope, lol!

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