DIY Super Speed Boat

[Music] i've been building this speedboat for the last few weeks it's a hydroplane that's propelled by air propellers so it's actually an airboat and it's designed to go as quickly as possible and maybe break a record or two the hull is made from pvc the sponsons or floats are made from wood and we've got some 3d printed parts and i'm going to be showing you exactly how i put this whole thing together step by step i've built a few different c-crafts on this channel before each connected in some way to my main interest of diy aerospace type projects this c-craft is essentially a scaled-up version of the hydroplane i built back in 2018. i'm interested in the way that boats like this use lift to plane across the surface of the water with minimum drag hydroplanes are able to go way way faster than hydrofoils like the couple i built back in january as they skim along on three small contact points hydrofoils are inherently draggier as they use submerged underwater wings that usually have to displace far more water one famous example of an extremely fast and successful hydroplane is bluebird k7 a boat that set several world records and reached a top speed of over 300 miles an hour using a turbojet engine from a fighter jet at such extreme speeds hydroplanes have to ride a very fine line and have to be perfectly balanced to stay on the water and not take off entirely so i wanted to build a craft of my own to ride this line and with upgrades and tweaks push towards greater and greater all-out straight-line speed i've decided to build an airboat to see how close i can get to the existing rc airboat record of 103 miles an hour set by dan jones in 2016. this therefore is the first episode of an ongoing series starting with the fundamentals such as checking to see that the thing actually floats in a moment we're going to put it on the lake and see how it performs for the very first time but not before i show you how it was built so let's see how i put this whole thing together to get started with my design i used fusion 360 to flesh out my sketches and turn them into an accurate 3d model this was done to help me decide on the scale of the boat and a few key choices such as what the materials were going to be for each section of the boat i decided to build the sponsons of the boat the big lifty float things at the front from wood so jumped into adobe illustrator to design them in 2d these two dimensional parts were made to be locked together using tabs and slots this would help to accelerate the build as i could assemble the pieces like a big lego kit i then cut my design on three millimeter plywood using a laser cutter but hold on a minute how does i come up with this design in the first place i largely based this new craft on the previous hydroplane but massively scaled up the power and increased the dimensions a little bit the theory with how this configuration with the airboat propellers work is that the high center of thrust pushes the nose down and lifts the back end out of the water the sponsons push back with their lift and keep everything nicely in equilibrium as with a smaller first hydroplane i went with a twin motor setup with these beastie 4258 motors they should be capable of producing 1800 watts of power and many many kilograms of thrust each on a 6s lipo when paired with these massive 16 inch props the rear prop has a more aggressive pitch than the forward one this is because it will be spinning in faster flowing air created by the first prop right then now we know what we're building onwards with the build [Music] i used superglue to stick the sponsors together piece by piece the tabs and slots drawn up earlier came in very useful here [Music] i ordered a couple of 200 millimeter diameter pvc pipes to use as the hull of the boat they're tough and waterproof but needed some reinforcement so i made a frame for them [Music] the pvc was a bit longer than i needed so i had to cut it to size to do this i wrapped some masking tape around the tube and attacked it with a saw taking my time to work around bit by bit until i had cut through now it was time to glue the hole together [Music] again i used gap filling super glue and some accelerator to bond the pvc halves together next i could glue the frame to the inside moving on to a slightly trickier bit i used some basic mattes to work out where the holes for some carbon booms needed to go before marking some paper and laying it over the hole these carbon booms were secured in place with epoxy whilst another hole was cut this time for a 30 millimeter motor pylon which was again made from carbon fiber i cut some mounting bracket things from some more three millimeter ply which could hold the pylon perfectly straight and firmly in position when all covered in some more epoxy returning to the sponsons i finished them up by sheeting the tops and bottom with bolsa wood before filling any gaps with filler and sanding it all smooth [Music] to waterproof many of the parts on this boat i decided to use aircraft dope which is a form of varnish that can be applied sanded applied again and basically entirely seals the wood when i had them all nice and shiny i took a drill to the sponsons to allow the carbon rods to pass through in hindsight i could have planned this all a bit better but winging it to some extent meant i had less chance of getting the holes in the wrong places [Music] i used my ender 3 to print out a nose cone design that i'd whipped up in fusion for this i experimented by using a setting called fars mode vas mode prints a single outside layer of your model to radically speed up the print time this nose cone only took 5 hours however the nose was clearly not strong enough and had some strange warps due to cooling and contracting during printing this meant i reverted to printing parts such as the tail in normal high speed modes the tail took around 19 hours to print after filling gaps sanding and waterproofing with some more dope i could attach this part to the hull a simple motor mount was designed to bolt the motors to the motor pylon originally i wanted to design a fancy tilting one which could be set at different thrust angles but i didn't really have time to develop and fix one when it inevitably exploded into a million pieces i made the tail skid from more plywood and waterproofed it in the future i might modify this part so i can attach various different planing skids and perhaps even an experimental hybrid hydrofoil wing that can help lift the rear out of the water before becoming an air stabilizer but maybe i'm getting a bit ahead of myself another print later and i had a new v2 nose cone that was immensely strong one of the last bits to do was the servo mount and rudder i ended up rushing the rudder assembly a little as you'll see later on so i will be revisiting this in a future video but for the servo all i needed to do was to make a little bracket to hold it in place before putting all the parts together in final assembly i had to paint the hydroplane priming the entire thing with car body primer i created an even base layer for the first coats of bright blue rust-oleum paint to bite into a tip with this sort of thing is to take your time do a fairly light coat at first and then build up with successive layers i chose blue to capture some of that bluebird spirit and also give me an excuse to name this thing bluebird just like donald campbell's it's a bit pretentious giving it a name like this but i suppose it would be quite cool if this bluebird did break a speed record of its own at some point after a few layers i could seal off the paint with some automotive lacquer going on to the home straight i could bolt the motors to the motor mount blocks with some three millimeter bolts and connect the escs all of this is a bit messy for now but can be improved later on a temporary battery mount was glued to the internal frame and positions for two batteries and a gps speed unit were added with velcro everything was pretty roughly taped on and velcroed in place on the inside of the hull but there's plenty of room inside to get in there and move things around later with that i could just about cram the hydroplane into my tiny hatchback and head to the lake for a first test float [Music] oh that was close i almost knelt in the poo there you filming yeah great great start to the test the day is here going to uh power up the boat put it on the lake and uh yeah lovely conditions this would only be a simple buoyancy test with a bit of maneuvering around just to see how the thing sat on the water speed was not the aim here but of course something still had to go wrong time is now let's do it what do you think mike you ready the plan is we're going to just stick it in the water obviously and then we're going to just keep it pretty close to the shore so that if it starts to sink or something um that i can just jump in and get it uh whereas if it's in the middle of the lake and it starts sinking it's game over your armbands i've not okay it takes a while for the propellers to stop so much inertia i might get the wet foot here why did i do that well it floats that's good although i'm not sure if it's going to stay floating let's say anything should i take it right back out again and see if anything's leaking yeah maybe there's no massive spurts of water so that's a good sign that's promising right okay excited the project doesn't work very well oh the rudder's falling off ah that's probably why that doesn't sound good well it might be a bit of a short test tonight boys okay the rudder i didn't this is the bit i was working on today and sort of rushed it so so clearly using glue isn't a great way of connecting a brass tube to some uh to a brass rudder oh let's just check if it's actually leaking right make a note of that let's plug that later so obviously i'd found two issues to fix before the next test but i still wanted to get a bit more footage for you viewers as the boat had tracked fairly straight previously i decided to point the boat at the other bank and let it go just so it could get to the other side right we'll just send it over there and then get some good shots of it just put it back on however as it turns out the boat had a mind of its own it's not gone towards the bank shall i just carry on and that was the second poor decision of the evening [Music] cruising towards the other side of the lake i did get a chance to observe a planing issue perhaps this was because i was in the mid point of the planing transition and i wasn't flooring it only opening the throttle up a little but it did make me think that maybe i needed a bigger tail skid reaching the other side i hoped the boat would remain pointing towards the shore for an easy recovery oh no it's going the wrong way now it's not a good time as well that's the desperate father chasing well that was a bit of an adventure wasn't it well we've saved it um yeah thankfully it was pointing the right direction as i got over here so i just powered it into the shore all right so obviously there's some things to improve on the boat like the rudder and also i think there are a few issues with it planing um so the way that it was sat in the water so we'll address that in the next video as mentioned we really need to address the planing issues with some mods and come back for some further testing when we can get the thing fully out of the water and riding the surface at increasing speeds despite this i'm really pleased with the slow speed stability the overall buoyancy and the lift of the floats i think this boat has some real potential moving forward so yeah let me know in the comments if you want to see me doing more on this boat and what your suggestions are for improvements click like if you enjoyed this video if you like what i'm doing and obviously if you're not subscribed already do that if you'd like and thank you very much to all of my patreons who make things like this possible i honestly wouldn't have been able to buy all these different components if it wasn't for your kind generosity cheers see you on the next one

Channel: ProjectAir

Views: 643,826

Keywords: James Whomsley, whomsley, James, projectair, 3d printing, rc, r/c, plane, airplane, model rocket, model speedboat, hydroplane, hydrofoil, rc hydrofoil, rc outrigger, how to make outrigger, bluebird k7, bluebird, Donald Campbell crash, rc airboat, fan powered airboat, rc airboat build, diy rocket, diy high power rocket, DIY model rocket, RC build, rc plane build, rc airplane build, how to make, how to make an rc, how to build an rc, rc car, rc buggy, rc boat, scratch, project air

Id: 0-_ckxOk704

Length: 14min 50sec (890 seconds)

Published: Fri Jul 24 2020