I was having a heck of a time trying to do my 4-color 3dchameleon install on my Ender3 V2 using the "classic" method, where the chameleon extruder simply loads the filament into the primary ender3 extruder, but the primary extruder is what is used during printing. I decided that eliminating the primary extruder and using the 3dchameleon as loader/unloader AND extruder was just going to simplify everything from the gcode to having one less step to go wrong. I followed this video (linked from the FAQ):
I think I've finally got my gcode figured out, and I'm able to successfully load and unload a single color (lets say extruder 2). Unfortunately, I noticed that when I use the same gcode on extruder 1, the extruder is moving in reverse.. which probably makes sense since one of the gears is on the opposite side. I realize I could just swap the extruder instructions in my load/unload by swapping positives and negatives, but that won't help during the actual printing where I might be switching between colors during print. How would I be able to have the extruder direction "inversed" for 2 of the 4 gears, using the above configuration?
Ok... it sounds like you have two different issues. 1) The extruder won't load. 2) Tip shaping. With #1, make sure your extruder can easily be manually loaded first... if that can't happen, then the 3D Chameleon can't load it, either. By doing that, you should not have to touch the extruder at all when loading... simply present the filament into the input of the extruder, and drive the motor... if it loads there, then the problem might be in the timing. With the timing, especially with geared steppers, it's important to match the speed that the 3D Chameleon is pushing the filament with the speed that the extruder is running. 25mm/s is the feed rate of the 3D Chameleon... and the extruder must be running at that feed rate before the filament touches the gears, so they can grip the filament. The default feed rate we have in the gcode generator is for a stock extruder, so you might have to adjust that speed. Also, make sure the filament is actually hitting the gears and not stopping too early. On #2, make sure you have the 1.8mm ID PTFE tube in the area where the filament can cool... that's the most important feature of tip shaping to prevent it from growing too fat and jamming. Now, with that said, not all filament swells... only PLA really does that. Experiment with different types and brands of filament... we've had huge success with Jessie PLA as well as Prusament PLA and PETG. The idea is that the filament should be allowed to cool below the glass transition point before it's removed from that 1.8 tube so that once it's extracted, it can't grow and become larger than any of the rest of the system, which is nominally 1.85mm ID.
I have been fighting this thing for months now, and I am steadily getting tired of it, I have tried multiple extruders, and they either "Grip too tight" SO the 3d chameleon can't feed to the main drive extruder, or "Grip too loose" So they don't feed/retract at all @_@ I was considering going "Jus tmake it the extruder but now I see that it's juts..a big mess here ...I'm really starting to regret buying this thing @_@ It's pLug and play, but its plug and play "If your extremely familiar with 3d printers and know how to debug and fix everything and knowledgable." >.<
All the files are in description of the video that describes it here: https://www.youtube.com/watch?v=ZxRBXXvShtQ It's also linked to in the first pinned comment in the previous video.
You need to use the old GCode Post Processor (works in PrusaSlicer only) to reverse the other two drives. Note that this doesn't work with Cura... but it can be run manually from the command line on the gcode if necessary, to support the other browsers. Also, as @gpgordon said, it is highly not recommended, as you'll need to develop all your own code and print profiles to get it to run. The real issue is that you're not mixing two different functions and it's exceedingly difficult to get both to work in the same unit... which is why we separated them out when we switched to the latest design. Can it work? Yes... but... it's very hard to get working.
Here's the video on how to install and use the post processor: https://www.youtube.com/watch?v=4mpSn5O6pAQ
Thanks @gpgordon , I thought about that as well but realized that my firmware (klipper) doesn't have the M92 command. Interesting on the 3dchameleon pinch, sounds like that could indeed be a problem. I'm actually having a heck of a time consistently getting filament through the split-adapter. It's usually not a problem to get through one of the four entrances, but often I have to push the filament with a lot of force manually to get it through the exit hole from that adapter :-(
Bill responded directly to one of my questions about extruder loading problems and noted that using the 3Dchameleon mk2 as the extruder is quite the headache.
As such, I wasn't going to go down that path but I did have a thought for your situation. If you were to want to reverse the direction of specific extruder I wonder if setting the steps/mm to a negative number in the extruder start/stop gcode would work in that instance? Not sure... and I'm sure it's not recommended. Maybe something like
M92 E-93.0; set to -93.0 steps per mm (extruder moves in the reverse sense????)
Then go back the other way with:
M92 E93.0; set to +93.0 steps per mm (moves in the normal sense?)
I've not tried it myself so I don't know if negative numbers are accepted, nor do I know how well it would work (guess this is a bit of a thought experiment and not backed by actual data). I think the bearings used in the 3Dchameleon to pinch the filament may hold with different strength and slipping might be more of a factor when trying to control filament flow with high precision?