2
$\begingroup$

I want to buy my first FDM printer, to print household items and wearable gadgets too big for my LCD resin one. Due to financing & tax reasons, what I'll buy now is what I will have for at least a year.

I was thinking about Prusa i3 MK3S+, and MMU2S looks really interesting and useful, especially to print water soluble supports. However, after reading reviews I hardly can justify buying it.

I have some technical experience, can make some things and once even built a 3 axis stepper motor system from scratch, and it worked. I have a resin LCD printer and have printed working parts. I still have NEMA17 motors, 4 of them.

Assuming I'll get Prusa i3 MK3S+, what else would I need to print and assemble MMU2S? Is there an official Bill Of Materials? Blueprints? STL files?

$\endgroup$

3 Answers 3

2
$\begingroup$

The MMU2S

The main setup of the MMU2S is one motor to choose which material is extruded, another to cut filament and move the coupler tube to the actual extruder. Then there are bearings, springs, screws, some rods, and a special chip.

The materials needed can be reconstructed from the Assembly instructions. Or you check out the help page here. It has:

  • Printable parts
  • spare part listing - which can be your guidance in purchasing some parts and used to order specialized hardware
  • Firmware
  • Hardware
  • aforementioned assembly instructions.
$\endgroup$
2
$\begingroup$

The MMU2S is quite a bit to put together, almost as long as the MK3S+ itself and the general consensus from a lot of the community is negative results for quite a lot of money. There are other options to try such as the Enraged Rabbit Carrot Feeder which is popular in the Voron community. Though there may be talks of not needing a wipe tower, the ERCF still needs one for non-voron machines, some the MMU2S has kinda fix with its wipe in setting in PS which allows for the change color to be wiped into the infill which will never be seen.

I don't want to say don't get the MMU2S but I'll definitely say even with a lot of skill its a very finicky add-on that many have claimed has stopped them from printing with it. Another notable option would be the Mosaic Palette 3 but the price tag is just about as much as a MK3S+ itself.

$\endgroup$
2
$\begingroup$

A more affordable solution is the SMuFF, it uses a simple 32-bit controller board, 2 NEMA 17 steppers, some optical end stops and a couple of sets of dual gear extruder gears (up to 12 colors, the default I also use is 5). Furthermore you need some screws and some rods. All printable parts are available from the Github page and there is a 178 page manual.

A word on soluble supports, I've printed PVA on Ultimaker printers, but it is tricky, it will clog easily. You would need a filament dryer, it needs to be dried before printing.

$\endgroup$
2
  • $\begingroup$ Nice, but can one just buy the electronics for it? I'm not sure if I want to solder all this from zero :) But sure this looks good $\endgroup$
    – Mołot
    Oct 26, 2022 at 22:52
  • 2
    $\begingroup$ You don't need to solder a lot, e.g. you don't need to use the cutter. Electronics are cheaper than MMU boards. Consider if you really need to print in multiple colors or want to attempt using PVA (the filament isn't cheap) and my personal experience with it caused me not to use it anymore even not on Ultimaker printers. $\endgroup$
    – 0scar
    Oct 26, 2022 at 22:58

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .