Can 3D printer work with enamel paints (or paints generally)? Are such printers available?

Question

There are lot of advices on the web how to paint the 3D printed objects, but generally they are advices for manual painting and this required special skills, especially if the object is small. My guess is that maybe 3D printer can lay the color layers as well? I am especially interested in the layering of enamel paints (which can be transparent and which can required high temperature heating afterwards). Medieval art has fine examples how detailed enamel art was created on the metal. Maybe something like this can be achieved with 3D printers as well?

If 3D priner with the paint-printing capability is not available generally then what are the prospects when such printer can be available? Maybe there are some early, experimental efforts to create such printer and maybe test devices are available?

Answer 1

So, there's not really anything like a 3D painting machine/robot like I think you're looking for, but there are printers that do fine detail with actual paint, usually oils, but not on 3D materials.

I found a thread that talks about canvas printing about 8 years ago, along with a couple of videos that show current machines doing just that, but that's still not what I think you're looking for.

There are also CNC machines that print with enamel paints, but these are usually for 2D again, and not very precise, as they are used for lapel pins that have cavities to hole the paint while it dries. I'm sure something like this could be used without the cavities, but you'd have to do a lot of testing to make sure the paint stays put or mixes as you want it.

Just like the oil printers, these enamel printers are likely very large and costly.

Alternatively

What might work for you is hydrodipping. There's a variety of methods to this, but one company has done a bunch of research on this and can do extremely accurate detail printing to "paint" 3D objects. The below video shows a variety of these hydrodipping techniques, but I've skipped to the most relevant part.

Here's the original video of what I think you're most interested in. It's not 3D printing in the way most of us think, but it's definitely a fantastic outcome.

To explain, if these videos are ever deleted: detailed prints are made of a 3D model to color it exactly the way it needs to be, sometimes using multiple steps and computer positioning to get the object colored/"painted" correctly and seamlessly. One part of the video shows how the software can accurately make straight lines on a human-contoured face mask, while another part shows how a blank, fully 3D cat model can have spots or stripes added in 3 steps with the seams being completely invisible as well as it detailed enough to be mistaken for a real housecat beyond first glance.

As it turns out, you can do (some of) this yourself. After doing some research, I've found that you can actually get blank (instead of pre-printed) films and use an off the shelf printer, as long as it meets certain requirements. (I'm not recommending a site, brand, or anything else, this is just the first/only option I can find. If you do more research, I'm sure there's more options out there.)

https://www.tsautop.com/blank-hydrographic-film/

https://www.tsautop.com/blank-hydrographic-water-transfer-printing-inkjet-printer-6-color-inks/

Answer 2

Painting Prints

Yes, you can paint your models with enamel paints. Actually, most paints will work. You might need to roughen the surface with sandpaper a tiny bit. Note that some spray paints might contain solvents that might soften or melt the prints, so read your ingredients!

...not with vitreous enamel

However, you can't use proper enamel, as that needs to be sintered after the paints have dried, and that will destroy your print unless you have used a metal-printer.

Printing Color

Now, if you want a printer to print a paste of vitreous enamel, you are looking for a paste printer. However, the paint for such a device needs to be very viscous, and the print quality (due to the large nozzle) will be far below what a skilled artisan can achieve. Also, you'd need one paste extruder per color.

Foils?

One could possibly work with foils, cutting them on a plotter and then carefully transferring them to the printed object. This would allow much finer details than a paste printer currently is able to create. Such a foil can also be printed upon by special printers - possibly achieving the full spectrum in a single application step.

Alternatively, one would use a "puzzle" of smaller pieces and apply each piece separately. The result might actually be somewhat similar to the Chromolith (Colored Stone) stonewares that had been created by Villeroy & Boch starting 1876.