
On The Fly
One of the selling features of the CETUS2 two filament 3D printer is its ability to change colors On The Fly (OTF). That claim is entirely true. But it took me some time to figure out how to do it well.
The primary ingredient with the CETUS2 is its very short “combined filament path" within its special extruder nozzle. The two filaments are introduced to each other (for single nozzle extrusion) very near the exit point of the nozzle.

In other articles, I mentioned the stringing, strands of light filament threads that are dragged out from the FDM print as the printer nozzle makes a non-printing jump move away from the printing surface to a new start location. It is caused by hot plastic flowing from the nozzle after it has been commanded to stop the flow.
Several adjustable factors are used to prevent this extra undesired flow. Retraction (reversing filament feed briefly) is the primary method to reduce or eliminate stringing. Temperature settings, retraction speed, retraction amount, pause, wipe, early stop, the list of “tweaks” seems endless. Sometimes it is an art rather than hard science to get the correct combination.

Is it ugly? It’s at least very LOUD. Red and Yellow seem to be circus colors perhaps. In any case it catches my eye.
It is the colors I had so it was the colors I used. I’ll call it a party bowl.
The print was made on the CETUS2 and ran for almost 24 hours. Each one of the vertical color post are printed in layer sequence, one at a time. then switch colors and repeat on the same layer (0.2mm high).

Yet another CETUS2 print project.
I received the Gecko file from a friend. I am sure it probably came from one of the on-line resources. I doubled the size from the original file and I believe I am responsile for slicing it into 3 layers. It is presently intended to be a two color print with the top and the bottom the same. Certainly it could be split into three parts for a three color print.
The reason I named this project "Oreo" is obviously the double "stuff" in the middle of the Gecko.