Tumble Coating 3D Prints – Part 3


You can also tumble coat in brass, as seen above, but there’s a few things you should know.  Brass may contain lead, even it says “lead free” (at least in California).  You probably shouldn’t be breathing in brass powder or using it to coat your children’s toys.

Brass screws are much more expensive and my first attempts with 150 or so smaller brass screws were not successful (#6 and #8, 0.5-0.75″).  Adding larger screws helped (#8 x 1.5″ screws seemed to work well), and so did decreasing the side of the barrel.  To reduce the barrel volume, I printed a filler cylinder that reduced volume of the barrel by about 25%.


If you find the gold look too tacky, you can try aging the brass. There are are liquids for aging brass that I need to to try. My attempt with vinegar, a spray bottle, and a plastic bag didn’t work so well, not quite the look I was going for.


A cheaper brass filler material might be useful for larger prints, and coincidentally, while thinking that in the middle of a hike, I came across a bunch of spent bullet casings.  I ended up packing out 3 and a half pounds of brass, which I plan to experiment with as a filler material.