Is there a good procedure to use in order to print with two different filaments?
I would like to try using a different filament for the raft.
Another application might be to print with 2 different colors.
You’ll need to manually add an M600 command to your gcode, and possibly also a temperature command if the two materials are not compatible that way. The two types of filament may or may not stick together, depending (you may want a soluble filament like PVA or HIPS, if you’re going to be using this strictly for rafts).
You can use multiple filaments via manual filament change with the GCode M600.
A new print head with two extruders is planned which makes this easier but who knows when that will be released…
Another way would be something like Mosaic Palette, but I am not sure if that is compatible with Snapmaker or if anyone has actually used it with a Snapmaker printer.
@dstarke the mosaic pallette is confirmed to be compatible with the Snapmaker by mosaic themselves, but as it fuses multiple colors into a single strand according to whatever color you need, using different types of filament (ie PLA with PETG) is out of the question.
This is not 100% true. Following the entry on their wiki page cases have been reported of successful multi-material prints. Obviously, it is harder to get done well, as you need to find a common print temperature, but not impossible. No one prevents you from printing PLA and PETG at 230°C for example.
@dstarke very true, but practicality is what then comes into question. Pretty much why you need an IDEX if you’re using PVA for support material, otherwise it just becomes incredibly challenging to get tuned just right to prevent the PVA from breaking down and clogging a 2-in-1-out dual extruder.
And dont forget the huge waste block generated with Mosaic Pallete. Either an IDEX, Robox Dual Type head (that is actually reliable) or a 2 into 1 mixing hot end and purge bucket are good options depending upon need.
Snmapmaker should really look at the Robox Dual Head and make it reliable… I had 4 robox machines at one point and were great until they didnt work… which was usually very soon. The head design had a few fundamental flaws,the main one being quality of materials and machining (screw inserts for seals were actually push fit and barely held due to machining issues) and bespoke m5x0.5 threaded nozzles. If anyone at snapmaker is interested I and another colleague have designs that would work (combined 60years Aerospace and design manufacturing skills between us)…
Purge bucket works well with Palette on the SM2.0 as the nozzle can be off the LHS of the build plate.
Snapmaker is already going to be coming out with a 2-in-2-out head. This is the prototype.
Yup but that seems a basic implementation unless the nozzles can be independently lifted out the way. Have a look at the Robox Dual head design with needle valve control which (As I say when it worked) was amazing. Nozzles on a Cam and are rotated sideways when not in use and needle valve to start and stop plastic flow without any ooze or need for retraction.
Was just let down by very poor manufacturing which led to failures see my video here CEL Robox Dual Head - typical failure mode - YouTube
I would think outside the box somewhat to explore directly using just one nozzle for multiple filaments. Ideally one nozzle that could support 3 filaments would be desirable.
Mechanically moving nozzles around over time could be problematic
You’re going to have some kind of moving parts no matter what you do, if you want a single-nozzle arrangement. If you don’t gate off the filament paths not in use, it would be difficult to avoid molten plastic backing up, and/or contamination of the extruded stream.
I’d stick with multiple nozzles and even the basic design of the Snapmaker prototype head, but have the nozzle in use pushed a bit further down than the others to reduce posible collision problems, dragging, etc. It wouldn’t have to be complex mechanically—just add some springs and a locking apparatus and tap into whatever drives the filament feed cog to push the nozzles down. Remove the lock, and the spring pulls the nozzle back up.