Introduction: Hovercraft!!!!

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Well, this is a hovercraft. For those of you who are looking for a rideable or remote-controlled hovercraft, look somewhere else. This is meant for people who are not yet into radio control (like yours truly) or for people who don't want to make a life sized one, but there are plans out there for free or... well, not free. This is a small hovercraft that will go and hover. If you want it to stop when the front of it hits something, i can show you how to do that. or not. whatever.
If you don't know what a hovercraft is, it will not rise above your head and float in the air. Motors inflate a plastic bag underneath, so it does float off the ground, but something is touching the ground. But only barely. The air then seeps out between the skirt and the ground, making it almost frictionless. That's why it doesn't require very much power.
Even if you have none of the parts at all, it should cost under 30$, and i can give you links for some of the parts. Remember, this is what I did, so you can leave ma a comment if you can't find a part, and hopefully I can help you.
You might also notice that I have two hovercrafts, one completely broken with all the parts taken off, and another shiny one that I'm working on as I make this instructable. The broken one is one that I made before, then someone stepped on it.
It is a completely original design, at least i didn't get the plans from anywhere. It doesn't require very much time. I should stop talking now and move on. Even though I have a lot more to say. Which I will say later.

Step 1: Find Your Parts

You don't need very many parts, but you don't need too little, either. Here's a list of what I used:

1) Two identical motors (I used the motors in two bug vacuums, the toy kind, but any 6-v motors should work) here, this should work: http://www.radioshack.com/product/index.jsp?productId=2914699 basically, two of the same motors

2) O.k., this is the hardest part to find. You need (in my case) two centrifugal fans (i don't know if i spelled that right). Those are the swirly kind. If you took apart the bug vacuums, the fans come with it. I used those. Any hand vacuum has one, or almost anything that sucks air. It seems to be hard to find a small one. If not, any computer fan should work, and you won't need two identical motors if it already has one.

3) Battery holders for your dual motors. (Or single computer fan) Again, make sure the holders hold the battery (or batteries) your motors need. I used a 4- AA battery holder with a switch built into it from here: http://www.radioshack.com/product/index.jsp?productId=2062253 for my two motors.

4) another motor, doesn't matter exactly, but I used a high-speed, powerful 18 v battery from radioshack: http://www.radioshack.com/product/index.jsp?productId=2102827&tab=summary

5) Now you need to find a fan that will fit on the end of the last motor. If the hole is too small, you could probably drill the hole very slightly bigger. If it's too big, I guess you could glue it.
now, here are two links where you don't have to worry about the fan fitting or not: http://www.sciencestuff.com/prod/P-m/0812 (for the motor) http://www.sciencestuff.com/prod/P-m/0823 and here for the fan

6) Battery holders for the single motor, in my case, two 9-v battery holders. As long as the holders hold the battery ( or batteries ) your motor needs.

7) a switch (preferably a push-on push-off switch, but any will work) If your battery holder doesn't have a switch built in, you need another one. Any kind.

8) wire (any gauge)

9) some much thicker, stronger wire, not for conducting electricity, but the wire mounts for the motors. (I used the straight portions of orchid-hanging wire) And make sure that it's not so thick you can't bend it.

10) all the batteries for your motors

11) a large foam meat tray or turkey roaster (like a big, deep metal pot, but thinner and square) and at least 13" by 9.75" ( 33 cm. by 24.5 cm) basically, the larger the better.

12) Plastic, like garbage bag or shopping bag plastic - not way too thick.

13) you also need some other glue, but not so powerful that you can't take it off or remove later, in case you make a mistake. I used hot glue.

14) you probably also want something to cut and strip wire.

15) this is optional. A hot glue gun.

160 something to cut the meat tray or turkey roaster

17) lastly, a tiny bit of cardboard and some glue, or, even better, a small screw and a matching bolt instead of glue

Everything will get clearer as we go along. (maybe) It's really not that much.

Step 2: The Skirt


This is where you use the plastic. You need to cut out a piece of plastic that is the same shape as the body of the hovercraft (the meat tray or turkey roaster) but bigger. I made mine two inches bigger (5.08 cm) and that actually seemed too small for a 10.5 by 15 inch base. (26 by 38 cm) I ended up making the skirt about 3.5 inches bigger ALL AROUND. (8.9 cm) That seemed to work.
Make sure you mark the center before you put on the skirt . Then you need to cut some small holes AROUND THE CENTER of the plastic. It helps to make the holes if you put some of the paper tape on the skirt and then put the holes in it. Make sure you LEAVE A BIT OF SPACE in the center of the holes, because that's where the cardboard bit will go. The first pic shows this. The little rectangle in the middle is where the cardboard piece should go. Poke a hole in the center of the plastic for the screw and bolt. It doesn't have to be big.
Mount the skirt on the base with some tape. make sure you completely seal up all of the holes except for the ones in the bottom. All you have to do is tape it along the bottom edge of your hovercraft, like in the last two pics. It might be a bit tricky around the corners, but it doesn't matter that much, as long as you SEAL THE HOLES!!!!
After you tape it on, poke a hole in the center of the body of the hovercraft for the screw to go through. Put the cardboard piece on the outside (bottom) of the skirt. put the bolt on the very end of the screw, and screw it so the cardboard is stuck there. The point of this is to keep the center of the skirt from bulging out. The vents are a bit hard to see in the THIRD pic, but they are there.

Step 3: Lift System

This is where the two identical motors come in. And the fans. And the thick wire. You need to cut two holes towards the front of the base, like in the 2nd pic. Make them slightly bigger than your fans. Bend that really thick wire into the shape in the fifth pic. The motors sit in the two sections that are lowered a bit. This is so the fans can blow all of the air into the skirt, so not very much will escape. You will make two of these. I'm telling you right now, this WILL DEPEND ON THE SIZE OF THE BASE! and where you cut your holes. Look at the 6th pic to see what you need. The red arrows in the center show how long the space in between the motors will be. On your base, the distance between the two holes is going to be the length of the two red arrows in the center. The two sets of red arrows on the ends will hold the motors from falling in to the holes, and sit on the base next to the hole. The two black arrows depend on the thickness of your motor. The motor has to sit snugly in the two lowered portions, and if you make it too wide, it will not be very stable. If it's too short, it won't really be able to sit comfortably. The two short, thick lines depend really on how tall your base is, and how far down you want your fans. Make sure the fans are below the edge of the base.It doesn't completely matter, as long as the fans are under the base and "in the skirt". If you want, put some soft foam on the bottoms of the fans, just in case, so it doesn't rip the plastic. When you have it settled and bent, glue the motors on the wires, the lowered part, one wire on either side of the axle of the motor, parallel. I used hot glue which will keep it still, but i can remove the motors if I make a mistake or it breaks again. Then lower the fans into the hole, with the motors attached. Sit them in there, but don't glue everything down. I wired up the two motors in parallel, and switched it on. It worked! Now try pushing the hovercraft on a smooth surface. If it doesn't go,
A) try making the vents a bit larger, or put more of them.
B) make sure both the motors are going in the same direction.
C) reverse the polarity of the battery to make the motors spin in the opposite direction.
D) Make sure the skirt has no leaks.
E) Make sure the air from the motors is going in the skirt
I'm not very good at explaining, just look at the pics or leave me a comment. The first pic helps a lot.

If you have a computer fan, just cut a hole the size of the assembly, and glue it in there. Not as hard, but i've never tried it to see if it works. This fan should work: where it says MUFFIN BONANZA, the 6th one on the list.

http://www.sciplus.com/search.cfm/term/fan/start/12/maxrows/11/srch.fp/1 or look around for a decent-sized one.
***This link only points you out to the "fans" page...they always change their website depending on what they get. ***
Still, they usually have several different computer fans.


when you're done with this step, CONGRATULATIONS!!!! you just finished the two most confusing steps of this project: the skirt and the lift system. At least, it's confusing when I explain it.

Step 4: Propulsion System

kind of obvious. You obviously need a way to make the hovercraft go forward. so, you need a fan at the back. First, find your motor, fan, and more of the thick wire.
Now, bend the wire into the shape you see in the 1st pic. Make two of these.
O.k., now remember I couldn't get the image notes to work. I just have to explain in words. I'm just going to explain every picture. The first pic shows how the mount looks. remember to make two of them. The second pic has a section in a rounded "box". That is the part that will be in contact with the motor, that you have to bend around and on the motor to get the curvature right. By that I mean press the wire on the motor until it bends and is the same curvature of the motor. The third is just the little flat part that comes off the curved part, it doesn't really matter how long. Maybe about the the thickness of your pinky finger. It really doesn't matter that much. The fourth pic shows the part of the stand that will keep the fan from hitting the ground or any thing else. It depends on how big your fan is. You need to make it tall enough so the propeller doesn't hit anything. The fourth pic is to help it stand up. you need to bend the wire 90 degrees out from the long segment (the part before) , but make sure it's flat. Then, from there, bend them up 90 degrees so that now there are two ends sticking out. It probably will not stand up on its own, you need another one, the motor in between, and tape and glue to make it stable. Set them up so that the ends sticking out are away from each other, then spread them out so that the motor can sit on both of them. See the 4th to last and 5th to last pics. Then you need to attach the two little leg parts on the base of the hovercraft, and spin the fan with your fingers to make sure it doesn't hit anything. The third to last pic is of the fan when its mounted on. Again, I'm not very good at explaining, so look at the pics or give me a comment.

Step 5: Wire It Up

First, make sure everything has wires. The switch, the motors, the battery packs and holders, etc.
If you have two motors, What I did is hook them up in parallel. I know that that isn't a very good idea, because it drains the batteries really quickly, but that's all I could think of to keep the weight down. I also used lithium batteries for my dual motors because they are more powerful. Make sure that when you hook up the motors that both motors go in the same direction. If one doesn't, swap the wires of that one. Look at the first pic. Now hook up the positive of the battery to one pair of bare wire and the negative of the battery to the other bare end. Turn it on. The skirt should inflate. If it doesn't, reverse the battery polarity. If it still doesn't inflate, the battery could be too weak, the skirt has holes, or the entire thing is too heavy. Usually it's because of the battery polarity. also make sure the fans spin in the same direction. By that i mean one fan might be swirling outwards while the other swirls inwards. If that happens, then you can reverse the polarity of one motor. If your battery holder does not have a switch, just connect the one wire from it on one bare end of the motor, and the other wire to the battery pack wire. Basically, the two negatives of the motor hook up to the negative of the battery while the two positives of the motors hook up to the positive of the battery. Or vice versa. Whichever inflates your skirt. Then you put a switch in between the battery and the motors. For the propulsion, hook up the batteries, with the push-on push-off button. Again, just hook up the batteries to the motor, making sure the fan blows AWAY FROM THE HOVERCRAFT! Then if you want the propulsion fan to turn off when it hits the wall, mount the push button at the front.

Step 6: Finish Up.

You will need some tweaking. Do what I did with the lift motors to get them to lift. Seal the skirt more. make it stronger. Balance the hovercraft out more. Whatever. Leave me a comment if you have a question. which I know you will. Because i really don't explain well. And with too many words. There might be a rudder system a bit later, but not remote-controlled. One where you move the rudders with your hands so they stay there. If you get it done, by no means should you leave it alone. Try upgrading it to give it better control. I don't know. Remember to rate it and leave me a comment. GOOD LUCK!
(you will need it with my explaining)