Hi VC, if they are gonna be so big - go for an IC engine like those of a small generator or a leaf blower, batteries and motors may or may not help based of your selection, to get the exact form my suggestion would be to model it approximately to scale - see who has a cnc router and get it carved out of styrofoam and join em, then painting would be nice on styrofoam.

have fun in your builds.!

https://sites.google.com/site/sevclubbangalore/

Quote
We were out from the morning testing the Hovercraft and returned a short while ago

Dear VC,
How is it doing?? how do you control the skirt??

Vishwas

Sir, can the design of the skirt be improved?

Posting some new pictures for your reference. I had modded the skirt for better performance and aesthetic appeal but had neglected to post the updated pics. Here they are. Two layers of Nitrile pipes have been used. Hot glued together to prevent air seepage from the sides/joints.

Ohk... This is a good design... Thank You Sir...

VC Sir...its awesome machine...it inspires me to brush out my old model...i will rework on it and make it even better,,,thanks for the idea...

VC   sir ,

I am trying to build  a  small size  Compact  hover craft ...  and  need  some   advice  ....
I am using   brushed motors (20,000 rpm at no load)   one for cushioning  and other for propulsion .....       which propeller  will be appropriate  for  the motor setup ...
i am using  coro  as the base     .......   is coro  good  or  shall i use  Deperon ?? ...     


total weight   would  be around  400-450 gms .....


regards   
-Ajith

Without knowing your battery / ESC setup, it will be very difficult for me to recommend a prop. I would build my model around 6 X 4 or 6 X 3 props.

I have never used depron as a base and have always relied upon coro, with great results.

Could you please post some pictures of your design and the motors?

Cheers!

hi VC.
try an umbrella manufacturer...that is similar type of material.
I like your work
regards
don

The umbrella material is more rigid and a skirt made out of it requires a lot more thrust to fill up. Rip stop is much better suited for smaller crafts.

That's my experience as well. I tried the umbrella material too but it's not as good as rip-stop.

VC  sir  i am  thinking  to  use  a 2200 mAh  Li-Po   for  both  lift &  Propulsion  motor s ....   as they require about  1.5 Amp

and  the  ESC    is   custom made  , made to  control both motors ....

as this  is  my first  one  i  want to build  a small sized one  some thing like in the  pic .... 


VC  sir   like in the  last  pic  Do we need  a  horizontal-plate   like  structure  between  the  skirt  as shown ... ??

so  as  VC  sir  said  shall also  use  6*4   or 6*5  propeller ??


can i use  a 2200 mAh  Lipo     to supply  current about 1.5  amp ??

1. I think that can be done - 2200maH should be sufficient to drive both motors
2. You need to control the speed of the Thruster. The Lifter can be a simple on/off mechanism
3. I have never used that plate for any of my models. However, I have used something similar in my first model with holes drilled around the circumference. That was for a model where a single fan provided both lift and thrust.

VC sir, I guess the motor in the pic 'm.jpg' in #87 is the 'johnson' motor you were referring to. It is available for around 300. Can it be used to directly drive a prop (for the lift fan)? Would an EDF (brushed) be better?

No way! Compared to this motor (I have several of them) the Johnson is a monster. Wait a moment, i will weigh them and give you the exact specs.

Okay, I get the point!

The below site explains the construction of a hovercraft using an EDF for lifting. Is there any advantage in using an EDF over a normal setup?
http://www.raymondclan.com/hover/hover.html

Ok here are the comparative specs. ALL FIGURES ARE APPROXIMATE

The motor in the picture weighs 75 grams while the Johnson weighs 180 grams.

Picture above:

Can dia: 25mm
Can length: 38mm

Johnson:

Can dia: 40mm
Can length : 65mm

Hope this dispels any confusion.

Vc  sir  ,

My  model  will be  Aprox  50 *35  cm    weighing around  450-500 gm.

will the above motor  with a 6*4   propeller    for  both        propulsion and  lifter   each  ??

where  can i get those  Johnson  motors  locally   in india ??

have you applied the airboat theory for this hovercraft?

I will assume that the last question is directed at me.

No this is not an airboat. It actually directs a part of the prop airflow through the duct and into a plenum chamber. This air is then somewhat compressed and exits through holes at the bottom of the hull, creating an air cushion.

thanks for the information

 

Quote from: ajith on July 31, 2011, 01:44:06 PM
Vc  sir  ,

My  model  will be  Aprox  50 *35  cm    weighing around  450-500 gm.

will the above motor  with a 6*4   propeller    for  both        propulsion and  lifter   each  ??

where  can i get those  Johnson  motors  locally   in india ??

I have a couple of the 25mm diameter johnson motors...If interested then PM me...

How much do you want for the motors?