However, using lightweight RC gear usually raises the build cost. So in this project, I explored hacking a cheap toy RC car (scale 1/64) for the RC gear. It turned out to be fairly simple. One thing was less so: dealing with the very thin gauge copper wire these micro cars use for their magnetic steering actuator. However, for a workshop, I worked out at easier alternative, as shown in the last step.
The cheapest version uses an 11” latex balloon (a common party balloon), well inflated with helium to carry about 10g. The propellers are very simple and made from scratch (See step 5).
The result is small blimp that is suitable to fly at home or in somewhat larger halls. It can even fight some minor air drafts, but as for any small blimp, forget about flying outdoors.
The weight of the blimp is trimmed till it sinks slowly when no power is applied. The main motor pushes it forwards and upwards simultaneously. Dosing the forwards command allows flying at more or less the same level. Steering left and right is done with a tail motor. The controls on these cheap and tiny RC cars is on-off, not proportional. But actually that works better for the blimp than for the cars, as with the blimp you can use its inertia to your advantage.
Flight times easily exceed the driving time of the original Mini Racer used, reaching over 15 minutes.
Here is a video of the blimp flying: