Author: Eric Thorstensson / Source: Make: DIY Projects and Ideas for Makers
It all started when I crashed a DIY quadcopter and wanted to reuse the parts for something fun. This was on a weekend when I had a slight fever, so I had some spare time on my hands … and I had an old dream of building a hovercraft … as makers, you know how it goes!
So I put together some cardboard, trash bags, and electronics, and it just worked. Since then I’ve been refining the design, trying out different things and having lots of fun building hovercraft as big as 1 meter square. I’ve also had help from some awesome Norwegian makers from Makeadrone (makeadrone.net), who immediately started holding workshops building some of my early designs and nudged my company, Strawbees, in the right direction with improvements. Finally, we released it to the market as an educational experiment kit.
The entire idea of our cardboard hovercraft construction is having an easy platform for experimentation. We use a snap-on, snap-off motor system and low-cost materials so you can easily make fast, iterative design changes to the base, skirt, and steering fin. It’s a ton of fun, and hopefully it will help you learn some great product development skills.
And these babies are fast! They hover across land and sea at over 25mph (~40km/h). Create your own spectacular designs, and race them with your friends.
1. MAKE THE PROPELLER GUARD
You’ll start by building the items that will mount on top of the base, so you’ll know where to put your holes in the base. First, the propeller guard.
Find cheap toy “beach tennis” rackets made in durable plastic. Many of these are molded with a slot that’s perfect for cardboard; if not, you can just tape or glue the cardboard to the edge. A cardboard guard, in combination with the plastic grid, will stop things from hitting your propeller (and the other way around too of course). Make sure there’s room for your propeller to spin freely, then mark your cut and saw off the rackets at this point.
On one of the rackets, you need to make room for the motor pod. Align the pod and mark around it with a pencil, then cut on your line.
Place a length of string in the slot in the edge of the racket, and mark it to measure how long the cardboard for the guard should be. You can also use a flexible measuring tape.
Cut out the end template and place it on a piece of corrugated cardboard, parallel to the fluting in the cardboard.
This makes it easy to slot it into the racket later. Mark the first end’s contour and holes using the template. Then measure the distance (that you marked on the string) to the other side and mark the opposite end using the same template.
Finish the contour by cutting the ends along your marks and then cut the long edges between them. Round the corners if you want it cleaner looking; we chose not to in this tutorial.
Punch the four holes out with a pencil.
2. PREPARE THE BASE
Use the base template or measure a 25cm × 34cm square. For strength, make sure the fluting in the cardboard runs front-to-back on your hovercraft; otherwise it folds too easily in a crash. Cut the square out using the metal ruler.
Cut the 5cm × 5cm hole for the motor pod according to the template. Take note of the offset from the center; this position is important for the balance of the hovercraft. Depending on the weight of your electronics and propeller guard, you can try out different offsets to perfect your design. If your hovercraft is tail-heavy, move the assembly forward on the next base you make, and if it’s front-heavy, move it backward. You can also tape weights to your hovercraft to balance it before your build your next one.
Place your motor mount (see Steps 3 and 4) on top of the hole and mark the 4 holes for the motor pod. Do the same for the propeller guard. Make sure the propeller guard leaves enough room for the motor and propeller. Punch the holes with a pencil.
Fold the round head of the Strawbees flat against the base bottom and secure with tape. You need 8 Strawbees per base; you can reuse them after this one is trashed.
3. 3D-PRINTED MOTOR POD
If you have access to a 3D printer, follow this step; if not, go to Step 4.
The 3D-printed motor pod comes in two pieces: the servo goes in the motor mount, and the brushless motor goes in the motor pod. Modify the mounting holes if necessary to fit your motors.
Mount the servo and then connect it to the corresponding channel on the receiver. Put the receiver and electronic speed control (ESC) into the motor pod and secure with double-sided tape. Make sure there’s room for the battery .
The post DIY R/C Hovercraft From Cardboard and Trash Bags appeared first on FeedBox.