DIY Simple RC Airboat - 3s 2300kv 6in Triple-props

It's been years since my last instructable . Thank you, any comment will help me a lot to improve .

The Airboat , Hovercraft , Water plane are RC projects that i wanted to make for long time ago because they are fun and easier to build than other RC projects . But i don't want to make it a bad project , i have to make them really practical and durable , that why i postponed my IDEAS for YEARS ! until now :( . Late than nothing .

So this Instructable is about an Airboat :)

- 36 cm length x 20 cm width .

Let's start with these STEPs :

Pick your electronic components , radio controlled hobby components , in fact .
Create the boat's body with PVC water pipe .
Motor holder base and cover frame .
Rudder and servo.
Finishing the body .

It's really a DIY !

Step 1: Motor , Propeller , ESC , Battery ,Tx, Rx and Servo .

So ,

Do you have old motor which comes with the prop from old RC plane , quad , ... ?
I have some from old quadcopter , also the the ESC , only 1 still works , lucky me . And the prop i'd never used since i have a lot of 6in-5in bi-blades props in spare .

The motor is 2300kv , can be used with 3s battery , prop is triple-blades 6x45(152.4mm) . Remember don't pick wrong rotation direction of the motor and the prop !

For mine :

I have a CCW rotation direction motor (white nut) . So the prop should be the "R" IF I WANT TO BLOW UP .

Please check the first 4 images .

20A ESC from old quad , it's a Skywalker 20A , 5th photo .
Tiny servo 1kg (it's enough) , 5th photo .
GT3C car/boat 3 channels transmission system :) with Rx of course , 6th photo .
3S 2000 mAH Li-Po from a quad .

How to calibrate the throttle with the ESC , please check the video .
ESC Calibrating .

Then , test the thrust , it looked good .

Step 2: Boat Body - :) Hard Part .

I will go straight up , i wish we have some plastic plate which is light and durable like carbon fiber plate , it'll be the best but the price is not that easy , and i would design a fine CNC body if i have to use carbon fiber plate . So , just DIY from cheaper material , the PVC water pipe .

Cut an old pipe which is big enough for size of the boat then use heater to bend the pipe . I used epoxy glue attaching parts together . Used fiber tape to hold them together then applied the epoxy :) . Process of cutting is not really interesting .
Please see the video for gluing part .

Body Gluing

After that i used a grinder machine to flatten the surface of the body , in-side and out-side , make it look better and fine . So that i can apply a paint layer later .

I realised that the PVC plate is so heavy , that's why i changed the front upper cover made by a plastic plate which is only 1.5mm thick .

The rear upper plate is a pcb , a fiber plate , which i intended to put the motor and rudder on . It has to be taken apart if i change the body , i'd like to make it like that , but it has to be well-attached to the body .

Front upper plate

Step 3: Motor Mount Base and Protect Frame

Making the stand for the motor .
3 years ago , i had chance to work with CNC machine and it was really helpful to create hobby parts .
Nowaday , we can easily create them from the 3D printer with a better price .

The one i use for this project is a mount part i had created couple years ago for the Y-3 tricopter 's tail , a rotating one with servo controlling . Anyway , you can use any of mount part (bracket) then make a stand for it . I just made it like " anything found in my house " :)

The black part in photos can be made from a square wooden piece or bending a small iron plate/ piece of aluminum ruler cut .

The stand ( aluminum bar ) was made from an old graphic card heat sink , then i bent it V shape . Having a Gas Torch is always helpful to bend 6061 Al like this . (last image)
Remember the height of this stand should be more than the prop radius ( >~126mm/2) .

Don't you have a Bend Vise ?

Mark the middle point . Measure the width of upper surface where your motor bracket mounted to this stand , it should be wide enough and flat .
Bend it .
Measure the needed height . Minus the Mounting feet to the boat's body ( 1cm width each side is enough for mine ) .
Bend it .
Drill some 3mm hole then mount them to the rear upper plate .

Please check the video . Motor mount and stand .

After we have a motor mounted with stand on the rear upper plate , it's time to make a protect frame for the "Engine" .

I used :

5mm flat carbon bar .
5mm carbon tube (3mm inside diameter) .
3mm carbon round bar .

Measure and drill 4 holes (5mm) on the rear upper plate where the frame covers above the motor and the prop . Then cut 4 of 5mm tube , length is enough , mine is 5cm .They're just same heigh . Then glue 5 tubes with epoxy , try to make them straight up, they will be the frame feet (plug-in). Please check the video for the process of measure , cut the tubes and glue them .

Then i left them to dry . Prepare the protect frame .

I cut 4 piece of 3mm round bar , length is 4cm . A part .

After the feet are tight glued with the rear upper plate . I measure the needed length for the 5mm flat carbon bar to make the frame , please check the video , they are not axact the dimension , just try to make it fully cover the props . ( #11 photo ) . Cut 2 flat carbon bars at the same approximate length . Glue A part to head of them using epoxy ( tape them together then use epoxy , then glue them again with super glue 502 - this is a tip), . Check the next photos . Don't use heat to bend the carbon fiber .

The other parts were attached after that using super glue only . Now it looks like a ladder . You may need to use some super glue at the tips (A part) to make them tightly fit the feet .

Check the video . Protect Frame .