My original reference picture is this:
(and the photoshopped drillcart I had made and posted a few pages ago.)
Although Seba's drill design is very cool-looking and might fit tf2's style better, it seems to be used almost only in sci-fi overscaled drill vehicles (
1,
2). My cart is much smaller, and will not be used for tunnel excavation (because that will make the cart even slower, and the fps probably even worse than if the players will get pinned to the drill), but for making a hole in some huge toxic cemicals tank, water dam or other important enemy facility. Also, considering this is my first model, I prefer to go with the simpler design, which is the bottle-opener one.