Thoughts on MMU2 from Experienced MMU1 users?  

Re: Thoughts on MMU2 from Experienced MMU1 users?

First, a brief history: I've been using a quad-material MK2 MMU for just over a year now, and have been extremely happy with the quality and reliability I get for both single- and multi-material prints. I am comfortable with multi-material printing in general, and the first generation Prusa Multi-Material Unit specifically.

The question is why do you want to upgrade then?
My suggestion would be to keep the current reliable printer you have. Never change a running system.

Re: Thoughts on MMU2 from Experienced MMU1 users?

The question is why do you want to upgrade then?
My suggestion would be to keep the current reliable printer you have. Never change a running system.

Perhaps my "brief history" was a bit too brief. Most importantly, I should have pointed out that I use my 3D printer as a hobbyist, maker, tinkerer, etc - I don't rely on it as a source of income. I enjoy creating multi-colour models, and I enjoy learning about the machines that print them. I am comfortable with the machine and process that I use now, and am interested in taking the next logical step forward. "Never change a running system", "Leave well enough alone", "If it ain't broke, don't fit it", etc. are all fine mantras for production systems, but they fly in the face of what drives hobbyists/tinkerers to do what they do! 😀

As it turns out, I didn't actually even ask for the upgrade to MMU2. I pre-ordered the MK2.5 upgrade very shortly after it was announced for an insanely low price thanks to the timing of my original MK2S order and discount vouchers sent out by PR. At the time I was completely new to 3D printing, and the idea of the spring steel sheet rather than having to peel, pry and scrape my prints free from the bed was what sold me. I also paid for the upgrade to the Multi-Material unit, which - at that time - essentially just added filament sensors to the existing unit (and was also very inexpensive). When PR announced the MMU2 many months later, they also announced that anyone who had pre-ordered the MMU upgrade for the MK2.5 back at the dawn of time would automatically get upgraded to the MMU2 instead. Awesome!

I suppose my original question was a bit off the mark, as I inadvertently implied I was concerned primarily about reliability. I don't expect any 3D printer at this level to be perfectly reliable. I expect to have to tinker, adjust, experiment, etc, but I also expect the device to eventually work as advertised, without having to sit there and supervise the entire process each and every time. I have no doubt that the MMU2 will do this - if not now then eventually. I'm just curious if people who are familiar with the ins and outs of multimaterial printing (pun absolutely intended!) feel that this unit is ready for use, or do they feel that that there are legitimate hardware / firmware issues that need to be resolved before this unit can be considered reasonably reliable.

Re: Thoughts on MMU2 from Experienced MMU1 users?

I'm just curious if people who are familiar with the ins and outs of multimaterial printing (pun absolutely intended!) feel that this unit is ready for use, or do they feel that that there are legitimate hardware / firmware issues that need to be resolved before this unit can be considered reasonably reliable.

Got it. As a long MK2/MK3 user and new to MMU2 unit user (added it to my MK3) I can tell that the MMU2 is already pretty reliable. But there are still many smaller and bigger software flaws that I would like to see fixed.
Most likely if you upgrade now, you will feel a step back from your current setup in terms of reliability but a huge step forward in terms of maintenance. Removable build plate and pretty easy and fast to open MMU2 makes it very easy to fix any jams.

In the last couple weeks, after my MMU2 unit arrived I've printed already successfully many > 20 hours multi color prints with different filament brands. (range from 195C - 215C). In my opinion it's already in a pretty good state but I'm pretty sure there are many people who will disagree :).

Re: Thoughts on MMU2 from Experienced MMU1 users?

I'm excited about the upgrade, but a bit concerned about the surprising amount of negative feedback (on these forums and elsewhere) regarding the MMU2 specifically, and the MK3/MK2.5 in general.

Compare to the amount of negative feedback about the MMU1!

I never owned the original MMU so I can't compare them directly, but given the complexity of multimaterial printing in general I think the negative feedback isn't that bad. There was also a lot of initial negative feedback about the MK3, but that's mostly settled down as Prusa has gotten the kinks worked out of the product and production. Just don't mention "powder coated build plate."

I've found the MMU2 to require a fair bit of tinkering and practice, but once you get over the learning curve it's fairly reliable. Not 100% yet, but once nice feature of the MMU2 is it's trivially easy to disable and go back to a stock single-material printer.

Re: Thoughts on MMU2 from Experienced MMU1 users?

Thanks for the responses and feedback!

In the last couple weeks, after my MMU2 unit arrived I've printed already successfully many > 20 hours multi color prints with different filament brands. (range from 195C - 215C). In my opinion it's already in a pretty good state but I'm pretty sure there are many people who will disagree :).

I've read through your thread on this forum about your first few days with the MMU2, and it seemed like your experience was very similar to what I found with the MMU1 - take your time getting it installed, follow the instructions, don't cut corners, and follow troubleshooting best practices if issues come up. Like you, I was braced for all sorts of issues based on negative feedback in the forums, and was pleasantly surprised to find that it worked reasonably well with default settings out of the box. It continues to work exceptionally well with a few minor adjustments and improvements.

Compare to the amount of negative feedback about the MMU1!

I guess that's what surprised me most. When the MMU1 was released, there wasn't a whole lot of collective multi-material knowledge and experience to draw from, so it had a bit of a "wild west" feel to it. I figured this time around, with a sizeable number of experienced multi-material users out there, it would be easier to distinguish between general multi-material issues and problems specific to the MMU2. I suppose the fact that it's a complete re-design rather than a revision to the original makes it harder for current MMU1 users to jump in without direct MMU2 experience. (And it never helps when those who have issues pose their questions/complaints in ways that discourage the people who could help from responding...)

one nice feature of the MMU2 is it's trivially easy to disable and go back to a stock single-material printer.

That's one advantage over the MMU1 I hadn't considered. It's dead-simple to use it in single-material mode, but once you've converted an MK2s to an MK2 MMU there is no quick and easy way to go back to anything even close to stock - at least not without a heavily modified printer.

Again, thanks to both of you for the feedback. I should be receiving my MMU2 kit on Friday (according to UPS), and will be posting my observations about the MMU1 > MMU2 upgrade once I get it installed and have a few prints under my belt. Unfortunately, I've got a batch of Christmas Ornaments to model/modify and print for family before I do the upgrade, so I may have to let it sit for a couple of weeks. I'm not sure if I can ignore the bag of Haribos for that long...

Re: Thoughts on MMU2 from Experienced MMU1 users?

I have also been using MMMU1 and very happy with it and my MK2.5+MMU2 will arrive soon.
I am not planing to upgrade soon though, may rebuild another printer via zaribo.org 320 upgrade path.
It costs more but I think it will be a better machine., certainky larger.
I am already building corexy printer, vkingprinter.com, and may use the MUM 2 by retrofitting it somehow.
I think community based development can innovate faster. That can be a better option if you have reasons to
put the effort to it.

Re: Thoughts on MMU2 from Experienced MMU1 users?

Really just installed mine and still working out the multi color settings, but the single mode quality and speed I'm getting is just as good as pre-MMU2 with direct drive. After months of tinkering, I was never able to achieve direct drive speed and quality with the MMU1 so I removed it. MMU2 nailed the coffin on the MMU1 on day one for me.

Re: Thoughts on MMU2 from Experienced MMU1 users?

Really just installed mine and still working out the multi color settings, but the single mode quality and speed I'm getting is just as good as pre-MMU2 with direct drive. After months of tinkering, I was never able to achieve direct drive speed and quality with the MMU1 so I removed it. MMU2 nailed the coffin on the MMU1 on day one for me.

That's an interesting observation, and one I hadn't thought of - I may actually see an overall improvement in single-mode printing. When I installed the MMU1 I barely had any single-material printing experience (contrary to PR's recommendations, I know), so I never really knew what I was missing in terms of the single-material capabilities of the MK2S. I knew that I was giving up the 0.25mm nozzle option, but that seemed like a fair trade. I'm looking forward to seeing how it all works out with the MMU2.