Learning How To 2 Color Print On A RoVa3D

Posted by Travis on 26th Jul 2017

Hi everyone, my name is Travis and I'm the new 3D printer technician for ORD Solutions. 

I would like to tell you about my experiences with my first major project, printing multi-colored name tags. The name tags were printed with one red perimeter to create the letters with blue infill. 

I won't comment on everything I did, but I will highlight some of my problems and solutions (not necessarily in the order they occurred). Everything was done using Slic3r and Pronterface.

My first task was to adjust the printer ensuring the bed was level. See section 2.3.16 "Level the Print Bed" of the RoVa3D manual Rev B.

I set the Z-axis home to ensure that the nozzles were at the right height when printing. See section 2.3.18 "Setting Z home". 

This was tricky and required lots of trial and error. I adjusted this every print until the plastic was just sticking, but not too far as to avoid smearing. The final adjustments were very fine differing by 0.025mm.

I had to find the correct offset of the nozzles. See section 3.1.3 "Calculating nozzle offsets". This also required lots of trial and error and the final adjustments differed by 0.05mm.

The print kept having small bursts of plastic which ruined the print. I tried drying out the plastic because if it becomes damp, the slight bit of water will cause bubbles as the plastic is being melted, however, this did not fully solve the problem. I then tried replacing the nozzles which also did not solve the problem. 

Finally, I lowered the anti-ooze retraction distance to 2mm which solved the problem. This was because the plastic was being pulled too far back during movements causing the plastic to snap inside the nozzle leading to air bubbles.

My final issue was having the blue infill ooze out from the red perimeter. To solve this I changed the overlap value in Slic3r to be -50% (yes, negative). I also changed the skirt height to be the same number of layers as the actual print to ensure that a proper perimeter was printed at each level.

This was a great starter project, and I encourage anyone to start their multi-color printing journey with different colored perimeters/infill. It's difficult, but very rewarding when it works. As this was my first time working with a 3D printer, it took me many tries to get a final product: