3Oz Nickel Weight
I needed a tidy counterweight for my Drawbot. I tried designing some different cantilevered pen holders with little success but did learn some stuff along the way. First the basic pen holder works good with about 3 oz of weight hanging off it it for a sharpie. Second, as well as the ball bearings work- i'd rather use them for something else.
I threw this together with the intention of filling it with sand - but like half the the stuff on the internet the weight per cc was off but 2x on the site I found it on. Fortunately for me the design I came up with is also the perfect size for a stack of nickels.