Yes, I can. The SMuFF allows you running it in different operating modes:

• Normal or SMuFF Mode
  This is the standard mode, where the SMuFF operates with a common set of GCodes, i.e. Tx for switching the current tool. It can be used on a DDE (Direct Drive Extruder) as well as on a BSE (Bowden Style Extruder), whereas BSE has proven to work best so far.

• Prusa MMU2 Emulation Mode
  This mode, as the name says, emulates the Prusa MMU2 by listening to the very specific MMU2 GCode commands, such as C0, L0, U0...
  It's targeting a replacement of the MMU2. This mode has been tested against a "real" Prusa MK2 printer. This mode is supposed to be used on a DDE (Direct Drive Extruder) only and might need some firmware modifications when running on a Marlin 2.x printer.

• Shared Stepper Mode
  This mode is based on Normal Mode. It's especially for BSE because the SMuFF can switch to the internal Feeder stepper motor for tool change operations and back to the external Feeder stepper motor for printing. This way the SMuFF gains more control over the tool change without the need of modifying the printers firmware.
  More information on the "Shared Stepper" feature can be found here.

The SMuFF was built with compatibility in mind. Instead of focusing on one printer / controller / firmware only, I've designed it to serve multiple connectivity scenarios. This makes it versatile and independent from the device / firmware used to control it.

The pictures below show you some of the connectivity options.

Since all controllers which can be used for the SMuFF usually have more then one serial connection, you're able to connect multiple devices at once, i.e. the 3D printer and the PC/Laptop. This makes it very easy to set the SMuFF up and monitor what's going on, in case you need to trace down a malfunction.

Moreover, the dedicated controller allows the SMuFF to fully control the process of tool changing and use optimized algorithms to trigger and resolve errors (such as stall detection on stepper motors).

Please notice: Even though all these algorithms can be integrated into a printers firmware, they have to be ported onto different systems (Marlin, RepRap, Klipper, ...) which, in worst case, may overwhelm the existing ressources of the 3D printer controller (i.e. Flash, RAM, Ports). It'll also increase the prerequisites of the printer controller capabilities (i.e. up to seven stepper drivers depending on the printers basic configuration).

The major difference is how you connect the SMuFF to your printer.

In BSE mode, the SMuFF replaces your main extruder and therefore, the E0 stepper driver of your printer gets connected directly to the Feeder stepper motor of the SMuFF. The printers firmware (or some macro or plugin) is responsible for handling the filament either when printing or changing filaments.
My OctoPrint plugin and the Duet3D controller are based on this configuration.

In DDE mode, the printer still is connected to its own extruder and has to coordinate the tool change by sending the right commands at the right time to the SMuFF. Loading, unloading and selecting the filament is the task of the SMuFF.
The MMU2 option in Marlin 2.x bases on this configuration.

Yes, it does work on Marlin 2.x.
The easiest way to use the SMuFF with Marlin printers is through my OctoPrint plugin.
Another method is: Configuring the SMuFF for Prusa MMU2 Emulation Mode and setting up your 3D printer for a MMU2.

Yes, it does. Here's more about that topic.

The SMuFF needs very little prerequisites on the printers side. If you're running Marlin, make sure it's version 2.x. You may need updating the controller board on your 3D printer in order to get Marlin up and 2.x running. Even if you don't, I highly recommend getting a 32-bit controller board.

Please notice: Depending on the mode the SMuFF runs in, your controller needs to have a spare TTY serial port to establish the communication with the SMuFF.

It depends on how many materials you want to have, what parts you have spare and a couple of other things. The easiest way to get a pretty accurate price tag is to download the BOM and key in the prices you get from your dealer/store. The sheet will calculate an overall estimated price.
As a rule of thumb: Calculate 60 money units* (USD, EUR, GBP) per tool and you'll get a coarse price estimate.

* This base value assumes you're using the genuine Bondtech™ dual drive gears.

That's right, it doesn't come cheap.
The SMuFF utilizes the advanced Bondtech™ dual drive gears, which give it a superior reliability and thus it guarantees high speeds and constant quality for your prints.
As usual: Quality comes with a price tag!

No, you can't.
The SMuFF was built with the Bondtech™ gears in mind. Other gears simply won't fit because of their geometry and moreover, they won't give you the same force and reliability because they're non dual drive gears.

SMuFF V1 had these. I've never released it only because of the poor reliability in feeding filaments.

No.

You can do that. All you have to do is modify the firmware code, so that it supports your controller.

Please notice: 8-Bit controller boards are outdated. Their lack of ressources and performance won't allow you to compile the SMuFFs firmware.
That's most probably the reason why you've replaced the 8-Bit board of your printer with a 32-Bit version and now have a spare 8-Bit controller laying around, not knowing what to do with it.

Yes it does on BSE and DDE. Although, on BSE you must not use flexibles that are too flexi.

No, but It'll help.

Teaching Tech (a.k.a. Michael) has made a nice video on that topic. It focuses mainly on dual color / dual material slicing on different slicers. Though, the process shown is the same for more than two materials.

On Prusa Slicer 2.4 you don't even need to have a multi material model, you can create one on the fly within the slicer by "painting" your model.

That's the job of the slicer. If your slicer supports that feature, you're golden.

It depends. On Marlin 2.x the limit is 8 extruders/materials, 5 if you run it in MMU2 mode. The SMuFF firmware has a limit of 12 materials.
Before you ask how many materials you can use, ask yourself how many do you really need. In most cases, a 5 material version is sufficient.

It depends. Meanwhile the SMuFF firmware supports a hand full of different RepRap displays. If your display claims to be RepRap full graphics compatible, chances are that it'll work right away.

Please notice: Double check your wiring. Accidentally swapped power pins may damage either your controller, your display or even both.

No.

No.

There are several ways:

• Help others to build their SMuFF

• Improve the firmware and put a pull request on the Github repository

• Design a PCB for the display / encoder board

• Donate

• Create a local user group

The windowsill or mantelpiece are very suitable places. Though, be careful with the mantelpiece during the winter season!

So far, there's only one I know of. It's a Spanish group and it's located here.

If you run your own group, please let me know and I'll add it here.

Sure thing.

Any material your printer is able to handle.

Countless. 3! No, 5! No wait, I have no clue.

But here's a gallery on a Spanish community site showing of some SMuFF builds. Big thanks to user Raikkok, who created this website to give the Spanish community a place to share knowledge, thoughts and ideas (and pics, of course).

Those are not errors, those are warnings. They mostly come from the included libraries. As long as the final message says SUCCESS, you don't have to worry about.

Yes, you can. In fact, the SKR E3-DIP is the preferred choice. A list of supported boards is in the README.md of the firmware on Github or on the Wire up the controller board page.

No, but it makes life so much easier.
Meanwhile I've created the SMuFF-WI, which is able to overtake the functions of a display, though, it's nice to have a direct interface as you're in front of the SMuFF, trying to mess around with the settings.

No.
None of my SMuFFs knows how to take selfies.

Because it makes your life easier if you're not using the Filament-Cutter. The Prusa MMU2 heat break comes with a slightly larger bore (2.2 mm). This helps a lot if you can't get your filament tips shaped well (see Ramming).
Because of the bulged filament, the SMuFF won't be able to push the filament down into the hotend and it will get stuck in the heat break. A slightly larger bore gives you more space and thus less jams.

If you happen to have a MicroSwiss all metal hotend (i.e. for Creality printers) this comes with a 2.3 mm bore in the heat break, so you're fine with keeping this one.

Please notice: You don't need that specific heat break at all, if you're going to use the Filament-Cutter, which I'd recommend anyways.

Ramming is a technique which retracts and extrudes filament in different speeds and amounts, so that the filament tip gets a nice, not bulged shape. This technique is one of the essentials when it comes to tool changes / tip shaping.
Be aware that this method of shaping heavily depends on the type and brand of filament, the nozzle and also the temperatures you print with. It may take quite some time to setup your Ramming sequence perfectly in order to get nice and well shaped tips. Hence, I'd rather recommend using the Filament-Cutter.

You don't necessarily need one but it reduces the number of failed prints.
That's because the popular PTFE tube inside the heat break / hotend is prone to jamming. All metal hotends don't have this issue so I'd highly recommend using one.

Please notice: You may have to nudge up the printing temperature a bit when you switch to a all metal hotend.

Have a look at this page, it explains in detail how to move on.

I highly recommend it.
You don't need to use my SFB - any kind of filament buffer will do the job and save you from pulling out your hair, because the 13 hours print stopped after 12 hours just because your filaments became the Gordian knot.

The function of the relay board is to switch the stepper driver of the Feeder stepper motor back and forth between your 3D printer and the SMuFF. That's why it's also called Shared Stepper.
While the printer is printing, the Feeder is controlled by the stepper driver of your printer. When it comes to tool changes, the SMuFFs stepper driver takes over control. This way, the SMuFF has full control over the Feeder, without the need of an extensive communication with your printer (which would require some fundamental changes in the firmware of your printer).
Since the stepper driver controls the stepper motor using high voltage (12V/24V) and a high current of up to 2A, a relay (i.e. a mechanical switch) is the way to go.

Please notice: You have several options for the relay board, one of which is my special shrunken relay PCB, published on PCBWay.

Basically, it's a 3 way serial splitter. It's needed on the Duet3D/RRF controller if you want to connect your PanelDue display simultaneously, because the SMuFF is occupying the serial port used for the display.

Please notice: With the latest firmware version of the SMuFF (version 2.x and above) you have the option of using the 3rd serial port on the SKR controller to pass the data coming from the Duet3D to the PanelDue.
Although, the amount of serial ports on any controller is never enough. So, in case you're running out of serial ports, the SMuFF-Ifc is coming to the rescue.

As the name implies, it cuts the filament.
I've been experimenting a lot with tool changes and was mostly focused on the failures. One reason of failure is because the filament tip will bulge as you retract it from the hotend. A more elaborated answer you'll find here.

You decide. PLA works just as well as PETG, ASA or ABS. Although, ASA and ABS are prone to shrinking, and hence may ruin the function of the parts.

Rumors say, someone made one out of Bamboo - but I wouldn't rely on that!

No.
There are a couple of so called Y-Splitters out there for dual color / dual material. Some of which are even already integrated in the hotend. You're better off with that solution.

Nope.

No you can't.
The reason is, that the platform for LPC1768/1769 MCU's is yet not fully Arduino compatible in PlatformIO.

In fact, any controller that's not based on the STM32F103 will fail to compile, since some of the essential libraries used in the firmware aren't supporting different MCUs.

Please notice: The new SMuFF firmware version 3.0 (currently under development) will take care of that and enable you using other board based on the ST Microelectronics MCU family.

Have a look at your favorite RC / Hobby / Hardware Shop. They often have a collection of different materials, such as Carbon Fiber, Stainless Steel or Brass.

Or, if you're heading for the fast lane, have a look at this special offer!

Here's the portal to my secrets!

Nope, they're perfectly fine.
This is an advanced technique for 3D printing where some of the holes are covered by a 0.2 mm thin layer. Those layers are used to spare you from using lots of supports where they're not really needed. Your printer will simply bridge these regions and build the rest of the print upon it. After printing, remove those bridges with a drill or cutter knife.

Because I decided so.

Please notice: If you've purchased parts for V5 at some point, I'd like to encourage you to move on to V6, because V6 is the successor of V5 and utilizes most of the parts needed for V5.