Earlier today I was experimenting with multiple shades/colors and materials using my Prusa i3 Mk2s. I have some black PETG from Fused Filaments, and some natural NextPage PLA. I wanted to see if I could combine them, so I tried to make a minimalistic business card.
Designing The Card
I used 3DS Max to design this card. Virtually every 3D modeling software has tools that let you follow the basic steps that I outline here. I tried to keep it as simple as possible. The basic design idea is split into two parts –
- solid background in one color or material
- raised features like text/border/design in another color or material
I made the base of the card by creating a 90mmX50mmX0.4mm rectangle. I chamfered the edges so that it would be more comfortable to hold.
I made a text spline and then extruded it to be 0.4mm thick. Then I positioned it on top of the base.
I find that Arial Round MT Bold is a great font to use for 3D printing, because it has nice corners and good legibility.
I made an outline of the edge of the card, and positioned it on top of the base like I did with the text. It is 0.4mm thick, like the text.
I sliced the model using the latest version of Prusa3D Slic3r. I used the following settings on my Prusa i3 Mk2S:
- 100 micron layers (0.4mm standard Optimal setting)
- 215C 1st layer
- 205C PLA layers ( 2nd to 4th layer )
- 240C PETG layers ( 5th to 8th layer )
I uploaded the model to the Slic3r ColorPrint webpage and used their tool to modify the G-Code. I simply set it to request a color change after completing the background. When I inserted the PETG, I had to make sure to adjust the temperature to 240C using the tune option on the LCD panel.
I thought that it would be best to use my natural PLA for the background, and the PETG for text to get a sharp contrast. The opposite would work well, but I thought that the transparency of the natural PLA would be nice as a background. The PETG also requires a printing temperature of ~240C, so it has no problem adhering to a PLA surface. Printing PLA onto PETG might have adhesion problems, because of the lower printing temperature of PLA.
There was minor stringing with the PETG because I was using my standard PLA settings, and only changed the temperature during the color change. It still turned out quite nice considering how little effort I put into it. I started by printing one card, and then I printed six cards at once. Both batches turned out nice.
The cards are pretty flexible but still firm with a 0.4mm base and 0.4mm border. The text gives a really nice tactile feedback when you run your fingers across it. I’m going to try printing them with a base thickness of 0.6mm instead of 0.4mm. The 90mmX50mm size profile is standard, but you could go any direction with the shape or size or design. There’s so many options.
The PETG lettering stuck firmly to the PLA. I twisted, bent and crushed one of the cards and it didn’t break or lose letters. I had to use a knife to peel the letters off, and they were pretty stubborn. The borders didn’t stick as well as the letters, though. I was able to peel the border off of two cards with my fingernails. Perhaps it was too thin.
I am going to experiment with further modifying G-Code, so that I don’t have to manually adjust the temperature after a material switch. Maybe I should pick up some black PLA so I that I don’t have to fuss with temperatures.