Tired of remote control model hovercrafts how-to's? Want one that you and your friends can actually glide across the ground in style without spending a fortune on a kit? Well here you go!
This is our home made, fully functioning, rideable hoverboard! We do not have a propulsion or advanced steering system, but we will share them with you when we add them in the future.
This hovercraft took us a week to put together and get it to work because we had no directions to follow while building. With this instructable, you can build one in a single weekend and cut out all the problems you would encounter if you attempted it using only internet videos as your guide. It can be built for around 50- 60$ if you already have a leaf blower you can use, the rest of the cost is if you need to buy one.
You will be using some handheld power tools. Always wear eye protection or you may end up looking like a pirate for the rest of your life.
Hovercraft Test Fail Video: (absolutely ridiculous)
Step 1: Materials
Here is what you will need to build a hovercraft: Print this as a shopping list to mimimize trips to the store.
1. Leaf Blower (Preferably gas powered)
We used a Ryobi 200 mph 400 CFM 26 cc Blower and it works great. We got it refurbished on Ebay for $85.
2. A sheet of plywood (Oriented strand board)
They come 3/4" thick and are 4x9 feet. You can get this at Home Depot for $16.
3. Plastic sheet
You will want one sheet that can cover one side of the plywood with about 6" to spare around each of the sides. We used some plastic weed barrier for durability, but you could use a plastic paint tarp or a shower curtain. Read the dimensions to make sure you have enough to cover the board (in one piece is preferable, but you may have to sew two shower curtains together if your craft is going to be too big.
4. Construction Staples and Staple Gun
5. Tape (Duct tape will work decently, Gorilla Tape is highly recommended.)
1. Circular Saw (could be substituted for table saw or panel saw)
5. Screws (For basic hovercraft you need 1" long wood screws)
6. Tape Measure and Ruler
7. Sand Paper (Or a Dremel with sanding bit.)
1. Clear Plastic Window Well Cover
2. LED Light Strip
3. PVC Pipe and PVC adhesive. (contact cement will suffice)
4. Old shoes or rubber or foam.
5. Screws (1/2" and 3/4" lengths)
6 Zip ties
7. Another roll of tape to cover the exposed top of the plywood.
Step 2: The Plywood Base
Start by measuring the length and width dimensions that you want the hovercraft to be. We measured ours to be 40x80 inches. Our craft is in a rectangle shape with rounded corners, but feel free to think up your own shape if you want it different. Mark the lines with a pencil or marker and trim the edges off with a circular saw. Be sure to wear eye protection when using any kind of saw to prevent injury. See first two pictures.
Find the center of one end of the board (should be 20 inches in) then measure 6 inches from the end and put a mark on the center. Use a circular drill bit that fits the opening of your leaf blower (or is slightly bigger if you cant find the exact size) to drill a circular hole on the center mark 6 inches from the end. If you don't have access to a large circle cutting drill bit, you can drill a pilot hole with a large bit, then use the jigsaw to cut it out the best you can. Just be sure it is big enough to fit your leaf blowers nozzle into. See picture 3.
Then take a circular object and line it up with the sides of a corner of your plywood. Trace the edge of your circular object on the corners of the board. See fourth picture. If you want tighter curves on the corners, use a smaller circle. We used a large fire basin that has a 3 foot diameter to measure our corners.
Cut along the corner lines with a jigsaw for best results. If you feel that you need to have relief cuts you can put them in before you cut the corners. See fifth picture.
Sand the edges down so they do not have a sharp edge on them that might damage the plastic when you put it on. We used a sanding bit on a Dremel tool so that we did not have to use some old fashioned sand paper, but sand paper will do just fine if that is what you have.
Apply a layer of duct tape on the edge and pinch it over both sides evenly. See picture 8. This is to make the edges as smooth and safe as possible to prevent any plastic damage after you put it on.
Picture 10 shows a layer of gaff tape over the top side of our duct tape. We only added this because we thought the staples would stay in better when stapled through the tape and the plywood. If gaff tape is unavailable to you and you want to add this layer of tape, duct tape would be an alright substitute. If you don't like duct tape results, use Gorilla Tape.
You need to cut another board out of plywood with the circular saw (We used some leftover wood from a desk that had a finished side, but plywood works fine. That is why the Dremel picture is on different looking wood.) that measures 11 inches wide and 46 inches long. Trace around a roll of tape to round the edges of this small and skinny board with the jigsaw like you did the big plywood sheet. Sand the edges the same way, and apply tape to the edge the same way if you think you need it (we did not put the tape around ours). This is the board that will hold the middle of the plastic to the large board.
Step 3: The Skirt
Lay the plastic on top of the large base sheet of plywood. Remember that this is going to be the bottom of your craft and if you designated one side of your plywood to be the top, it should be facing down when you do this. Have the excess hang close to evenly over every side. There should be at least 6 inches of excess plastic all around to play it safe. Picture 1.
Lay the smaller board on top of the plastic. Use a tape measure to help center this board the best you can you can try to use a marker to mark the center lines to line up with, but it may be difficult if you are using black plastic. When you have it centered, screw it in place to hold it there tight. You are going to want to use 1 inch long screws so that they don't poke out the other side. If they do poke out the other side, you will have to grind the ends off (like we did in picture 3). Put a lot in to really hold this board in there. We put 10 screws down each side. Then it is highly recommended that you flip the entire thing over and put ten more screws down the middle from the top side, in one of our tests, this board came right out of the plywood because we did not put some in from the top side.
Lay the board down with the plastic and small board face down. Have the plastic be laying out flat around the base to work with it easily (picture 4). We did it on the grass to protect the plastic. Now is the time you should decide if you want the board to be up off the ground a few inches or only about an inch. The easy way would be to pull the plastic tight, fold it up over the top edge and start stapling it in place 1/2 of an inch from the edge, kind of like in picture 7. That would only lift the board up an inch above the ground at all times. If you want some additional clearance, like ours, then you have to do some measuring.
Here is how to have 4 inches of clearance above the ground when you are riding on your hovercraft (recommended and better looking way):
Measure 6 inches with a ruler from the edge of the board and mark it on the plastic with a marker, all the way around the base. This is just to trim the plastic to be easier to work with. See picture 4. Trim off the excess by following this 6" line with a pair of scissors, it should look like picture 5.
Now fold the plastic up over the top of the board and pull it tight. It is nice to have someone hold the plastic while you measure. Measure four inches from the edge of the board and mark it on the plastic with a marker. See picture 6 for reference. You need to do this around the entire board. Make your marks close together so they are easy to follow, or connect them with a line after you are done marking. This can be a little bit tricky around the corners, just do the best you can, you don't have to be exact, but try to keep it within a quarter of an inch of your measurements.
After marking the 4 inch marks across the underside of the plastic, (it is facing down when it is not folded over the side) start with a straight edge of your board. Bring the four inch line that you marked to about 1/2 inch away from the very edge of your plywood board and put a staple on that 4 inch line. You will be able to feel the edge of the duct tape boarder that you put around the edge of the board. If you staple right on the edge of where the duct tape ends, that is a good indicator of half an inch and you don't have to measure. What I am saying is staple the four inch line half an inch from the edge of your board (picture 7). We have our excess folded under near our 4 inch line, but we found out that it just made things more difficult that way, so you don't have to fold your excess back under. Put the staples about 1/4 inch apart until you go around the entire board (most time consuming and repetitive part), then trim the excess plastic off the top (if you did not fold it under like we did) but leave almost half an inch of the plastic after the staples. See picture 8.
Step 4: Putting Holes in the Skirt
Now for the part that gives us lift!
Lay a ruler along the edge of the small board you screwed in for how far away the holes should be. I used a half dollar piece to use as a cutting stencil and cut around the outside to make the holes. That makes them just under 1 1/2 Inches big. Do your best to evenly space 7 holes down the long sides, then two holes on each short end. If you want to make them more sturdy, put a square of tape over the area you are cutting out your hole. I like to use Gorilla Tape because it is black and is much better at sticking to things than regular duct tape, but it commands a price of $10 a roll. Just trace around the coin carefully with a utility razor for a clean circle.
Since the plastic was black and I just so happened to own a high powered blue laser, I just melted the plastic around the coin to cut these holes out, but it is a little bit faster to use a utility razor or a pair of scissors if you have nothing else. Always wear the laser glasses if you own a laser like this because looking at the intensely bright dot it makes is bad for your eyes.
It should look like picture 5 when you are done with it.
When you are done putting the holes in the skirt, flip the craft over and apply a layer of tape over the stapled edge of the plastic for an extra seal. Have half of the tape overlap the plastic and the other half on the plywood.
Step 5: Testing and Troubleshooting
Friction fit your leaf blower into the hole you cut out and start it up. The leaf blower we have has a throttle control leaver that helps keep it in full power all the time, which is why I recommend this model. If it does not start gliding across your driveway the instant you turn it on, don't panic, try getting on it. The leaf blower makes it back heavy with nothing else on, so unless you put some sort of counterweight on the front, it will drag a little in the back and not move. This can be a good thing if you don't want it hovering away with nobody on it. Other than that, if you built it the way that was illustrated in this instructable, it should work fine the first time, if not:
If it still is not going anywhere with you situated on it, lie face-down on it and feel around the edge where it meets the ground for a place where there is too much air escaping from under the hovercraft. It took us seriously 8 major adjustments and building a completely new hovercraft to finally come up with a few good tips.
Unfortunately, we have not had the opportunity to test if this hovercraft works on water, it is winter time and we live in the depths of the suburbs! I imagine that it does...
Problems you may encounter: (You probably varied from our hovercraft instructions to make your own version. Kudos to you risk takers!)
If you found air is easily escaping a certain place, turn over your craft and look at the bottom, odds are that it is a deep wrinkle that formed. The main reason a wrinkle will form is that the material you used is just too thick. If you doubled up layers, carefully cut off one of them so you don't have to redo the entire thing. If there is still a wrinkle, the small board under the main plywood may be too big. At first, our board was way too big, but after we cut it down to the size that we instructed, the wrinkles disappeared. We also doubled up our plastic and had to cut the outside layer off after all our patch attempts failed. A good rule of thumb is that you want a lot of skirt to be exposed on the bottom and a smaller board to get rid of wrinkles.
Dragging fabric preventing even contact with the ground:
After we fixed the wrinkles, we still had no idea why it was letting air out in uneven places. If you poke the skirt while it is inflated and it feels like there is a decent amount of air pressure, that is your problem. We first thought that the more rigid the skirt, the better stability we would have. We only had 4 holes going down each side of the small middle board. After we made 7 holes down the sides and 2 at each end, spaced fairly evenly, the craft glided across the ground perfectly. We noticed that it seemed like there was almost no pressure in the skirt, but it still maintained its shape and it sacrificed almost no clearance, so all the better. Keep the holes about an inch away from the board though, if you put them too far out you will have problems. Remember that you are creating a cushion of air, not using propulsion to get you off the ground, the bigger the cushion you are trying to make, the more problems you will encounter.
Leaf blower falls out of the hole easily:
If you wanted a quick fix, use duct tape. It will work just fine, but if you want something much more substantial and cool, check out our accessory step. If it is too loose in the hole, you can wrap duct tape around the leaf blower nozzle until it is thick enough that you have to shove it down in, then tape the nozzle to the board itself.
Leaf blower on low power:
Use duct tape to keep the trigger pulled in all the way. The model we used has a helpful switch on the side of the trigger that is easily locked in place with minimal tape.
Duct tape coming off easily:
Use Gorilla Tape. Superior in every way but cost.
Holes in skirt plastic:
We only found holes in our shower curtain model that we scrapped because the other plastic was far better. Most holes were due to poor handling and moving it around by hand. Taping up the holes will work as long as you are not putting long, tight strips on that prevent it from taking a proper shape upon inflation.
Help! My hovercraft just looks so bad!:
Read the next step for some customization and decorative ideas.
If you have a different question, feel free to ask and I will add it to the list.
Testing Fail Blooper Video:
Step 6: Customization (optional)
Here are a few ways to make your hovercraft look and perform better.
Covering the exposed plywood:
We used tape. It took 2 rolls of black Gorilla Tape to cover the entire surface. We started on the outside edge of the craft and moved to the middle, overlapping a little for good measure. You are going to want to use scissors to cut the strands off because tearing will make your fingers raw very quickly.
If you hate taping the leaf blower straight into the hole, just make a mount out of a leaf blower nozzle and a thick piece of scrap wood. First cut the end of a leaf blower attachment that hooks straight onto the blower itself. Cut it so that the open end will extend past the chunk of wood that you are going to put it through 1/2 an inch. Trace the opening on the wood and cut out the circle with the same drill bit you used on the plywood base for the hole. Trace a circular object (or measure two inches from the sides of the attachment and cut a square shape if you want a square) over the hole that will extend past the edge of the hole at least 2 inches. Cut out the ring of wood with a jigsaw and put the attachment through the hole. Put four screws of the appropriate length through the side of the ring or square with the attachment in it so they hold it in the middle and stick through the side of the plastic attachment about a half an inch (see picture 9 of Motor Mount). Cut a circle in the tape around the hole to expose the plywood. Spread wood glue around the exposed wood and stick the mount on. Screw in some screws to secure the mount down over the glue and hole, make sure the leaf blower will be facing the right way when you put it in. Feel the underside of the plastic where you screwed this into the board to be sure no screws are poking through the other side! They will rip your plastic! See the motor mount pictures for reference.
Be able to slow to a stop and steer a little. Making these out of PVC pipe is super cheap (about $10 for both) and anyone can do it. This is a simple and effective design. You can look at the step-by-step pictures we took to get a clear idea. Be sure to apply glue to every joint when attaching the PVC pipes together. You will need to cut two of each pieces so you can make two handles.
Use a plastic window well cover. The one we used is $20 at Home Depot. Have it be clear plastic and a mostly rounded shape, they have a few models for sale, so choose the one that you think would look best. To get it to be a bit taller and rounder, push in the sides so that it bows upwards. Use half inch screws to screw it down to the plywood then cover the rim in tape that matches your board.
Having LED light strips is what separated a good hovercraft from an awesome one. Buy a 16 foot strip of your choice color off Ebay for around $10. They come with a sticky side that makes attaching them to anything much easier. Don't be worried about how you are going to get them to light up. The best cheap way to do it is buy a 9V battery. They are the box ones with two nodes on the head. Just touch the two exposed wires dangling off the end of your light strip to these and they will instantly light up! It may not be quite as bright as powering the lights with a 12v power source, but they look bright enough to me. Use any tape to secure the wires to the battery.
Cut two of each lengths shown in the rail image to make two. Measure 7 inches from the sides and mark where the end caps for the rails will be. Drill three holes in the end of the caps to allow screws to fit through. Screw the ends down, then build the rail on them, glue the pieces together as you go. Use the images for reference.