Jacobs Hovercraft

[Stambo]

Jacob has been asking about a hovercraft for ages so this weekend we got stuck in and did it.
It's nothing flash but it is certainly functional.
It's all stuff I had lying around, some of it I had to improvise, but nothing beats a Kiwi dad when his kid has his heart set on seeing it go.
Most of it is 6mm ply wood, because that's what I had, motors are 28-26 1000kv NTM Propdrive.
Props are 8x4.5 and I am running some 30a ESCs that were rejected for multirotor use.
At the moment it is running 2 3s batteries but next outing we will use 4s for the thrust motor.
The skirt is a rubbish bin liner attached top and bottom.
I also have some polystyrene foam of sorts that came packed around a radiator, attached to the bottom with gaps at front and rear to allow bag inflation.
Hopefully this will float even with the lift motor off, if it does I will have to try it in a lake or pond.
We discovered that the rudder was not so good so I need to either give it more travel or maybe a two rudder setup.
There was a bit of a learning curve to driving it and once we got to grips with how it worked we started having a bit of fun.
At the moment it turns left better than right, and we found it turns much better at full throttle.

Sorry, no build pics or video really, I started with good intentions but it never happened.
Here is some completed pics, I'll upload the maiden video tomorrow.

2016-06-18 21.38.03.jpg (1.09 MiB) Viewed 8113 times

2016-06-19 22.25.14.jpg (1.13 MiB) Viewed 8113 times

2016-06-19 22.49.18.jpg (975.49 KiB) Viewed 8113 times

[Graham Lawrie]

That's really cool Stambo Might have a go at building one myself:)

[Derek]

That's real good guys! Well done!

[DOG]

I like that it's pretty nifty!

[Stambo]

Here's the video.

https://www.youtube.com/watch?v=JBbe2qe ... nel=Stambo

[Derek]

That's real good, Stambo! Very nice! To get it to turn...you may try adding two more rudders, so that you have 3. Space the other two rudders about an inch or so away from the middle rudder. That should help the craft turn better.

[DOG]

That's Nice job guys . Have you thought about trying over water? Enjoy it guys, pretty neat!

[Stambo]

That's real good, Stambo! Very nice! To get it to turn...you may try adding two more rudders, so that you have 3. Space the other two rudders about an inch or so away from the middle rudder. That should help the craft turn better.

Once we figured that it would only turn with fairly high throttle, kinda obvious when you think about it, left turns were a breeze.
I think once I give it a bit more rudder travel it should be fine.
Using a paperclip for a servo push rod probably does not help either.

That's Nice job guys . Have you thought about trying over water? Enjoy it guys, pretty neat!

Yup, water is on the agenda next time I have Jacob for the weekend.
I will do a float test first, I think the polystyrene base should help there.

[DOG]

That would be neat to see it go over water . I have a water skiing ferret that you can pull behind the hovercraft if you like to borrow Everyone has a water skiing squirrel

[Stambo]

I did a bit more work on Jacobs hovercraft today.
I extended the servo arm a bit, put a proper control rod with an adjustment and adjusted things so I would have more right rudder than left.
The reason for more right than left rudder is that with the lift prop rotating clockwise, there is a tendency for the craft to want to rotate counter clockwise.
This makes left turns quite easy but right needs a bit more assistance.
I will also use a 4s battery for the thrust motor.

Once the weather here allows, I will do another video to show if my adjustments have worked.
Don't worry, it won't be as long as the last one, I got a bit carried away with that one.
It does show how long it will last on a pair of batteries though.

Then when Jacob comes for his next weekend with me we will try it on water, there will off course be video of that, good or bad.

[Derek]

Sounds good buddy!

[DOG]

That would be to cool to see how the hovercraft maneuvers in water.

[cml001]

Love it!

[Graham Lawrie]

Way cool:)

[Lee]

Great job guys.
I keeps saying I should build a hovercraft, cause I have all the parts to make one.

[Stambo]

Well, we finally tried this machine on the water recently and it was a fail, the bag filled up with water.
I can see why and I think it will not be difficult to put it right.
The air intake to fill the bag is at the front and back in that open channel, at water level.
If I put a piece of ply down the channel and part way up the duct where the lift prop runs, it should still inflate but not allow water to get in.
That's my theory anyway.

[DOG]

Hey Stambo. This might sound silly but instead of plywood, use clear silicon caulk. Light weight and water proof. Just a guess.