With those pink battery connectors we have a lot of trouble pulling off them with brute force so I doubt they would come off in game unless they were hung off the back dragging
. But hey over engineering Is a a better safe then sorry approach. Nice job. Also did you pay for the ultimaker 2? I have some friends over the company really awesome guys But seriously good chose of 3d printers Ive had my hands on just about every 3d printer on the market(world makerfaire and ny 3d printing expo press passes) and I have to say aside its my favorite extrusion based 3d printer. Now let's see how long this ekocycle 3d printer lasts.