I was thinking of building a locomotive with a boiler that is 3 studs in diameter. Part #30360 fits the bill nicely, but I cannot think of a part that will fill the middle gap. Do you have any ideas on how to do that, or is there another part that is 3 studs in diameter that does the same job better?
Fig. 1 Part 30360 was produced by The Lego Group between 1999 and 2012.