RC India

Finally achieved a childhood dream. I have been wanting to do this since my schooldays. Tried it once in 1982 and didn't succeed. I have just completed her a couple of hours ago and she works like a dream! Didn't expect her to perform so well with a brushed motor. She is almost entirely built out of coroplast. My only regret is that I don't have a big enough place to give her full throttle and let her rip!

Details and videos soon to follow.

I would like to thank all the forum members for their valuable guidance and support. I am pleasantly tired now after 12 hours of continuous effort.

Warm regards,

VC

Construction : Coro reinfgorced with bamboo strips.
Skirt : Nitrile/Nitroprene Refrigerant pipe
Length : 66 cms
Beam   : 35 cms
AUW    : 350 grams
2 Ch Tx/Rx
Drive : DC Brushed Motor (25000 Rpm at no load). No load current 1amp/Stall Current 10amps. Torque 0.36 KgCm.
Servo : One unit weighing 8gms.

A video would add to the awesomeness ! :) 

And how did you do the black lines ?

Thank you! Black lines were painted on (temporarily) using a permanent marker. Video being posted shortly.............

the model looks superb, interesting material for skirt  ;)

looks jazzy

how do you get "air cushion" ( the hover part ) with only one motor ?

Huge air intake which grabs half the thrust from the prop and channels it into the skirt............. ;D

Trying to upload the video..............

Cheers!

VC

Looks neat and really clean. Video please!!

congrats sir
cant wait to see the video

Regards
Vaibhav

Ok Guys,

Here is the first video:

http://www.youtube.com/watch?v=bHDtW1mJy08

Cheers!

VC

It seems to be a bit under powered.......dont mind sir and you seems to be of my age....

Was trying it out at 1/3 Throttle as I don't have enough space. Recharging the batts now and will post a better video in a bigger place soon.

I am sure you are much younger than I am, I was born in 1964.

Cheers!

VC

but in the video theperson controlling seems to be under 20 it seems ytou have maintained a lot :D ;)

good job sir  :thumbsup:

"but in the video the person controlling seems to be under 20" - Botox, Plastic Surgery, Cosmetic Surgery, Facelifts, Shahnaz Hussein et al............... ;D ;D ;D ;D :giggle: :giggle: :giggle: :giggle:

 :bow:

VC

Some build pictures.......

And some more ............. Any questions are welcome.

Cheers!

VC

In order to reduce weight, I need to power this baby with AAA cells. She is now running on 8 X AA cells and with 8 X AAA, I can reduce the weight by another 35 - 40 grams. Can someone please let me know where I can buy AAA Cell holders? I have looked everywhere on the net. Would be willing to pay in advance if anyone can let me have 5 pieces AAA X 4 plastic battery holders.

Regards,

VC

VC,
Why not substitute it with a Lipo? Will be much lihter and you will get higher duration for same weight.

VC have you tried it over water yet?

Using LiPos would be the sensible thing to do, however, I would then need special chargers and equipment. I know that finally, for all my models, I am going to have to invest in LiPos, but for now, I am trying to stay away from that expense.

I was supposed to take her to a swimming pool today to try her out but we are now in the middle of a severe cyclonic squall. I guess that will have to wait till next weekend.

Cheers!

very nice VC. Waiting for more videos.

ashta

Thank you Sir!

Hi Members,

Resurrecting an old thread, with a very good reason, as will be evident in the days to follow. My scratchbuilt Hovercraft was lying dormant for the last 5 months and only today she's been upgraded to a Brushless motor, 6X4 prop, 18 A ESC. LiPo battery. Radio changed to Futaba Attack Tx/Rx. Video of the improved version follows.

If anyone has any experience of building a Griffon 2000, 8000TD or the LCAC 1, please drop me a PM with your contact numbers. If anyone has any practical experience of fabricating the Hovercraft skirt out of Rip Stop material or any other durable alternative (NOT GARBAGE BAGS), please PM me immediately. I will contact you,  I regret that I am not interested in discussing hobby class and / or experimental stuff that didn't work out. I've been there and done that.

Mark Porters sites / designs and plans have all been downloaded so don't take me there again. I need to hear from people who have actually constructed a Practical RC Hovercraft with an inflatable skirt that actually moved (not crawled) on land and water.

I regret that my usual niceties are not in place, forgive me. I am under tremendous pressure and I can't elaborate on that now.

IS THERE ANYBODY OUT THERE?

VC

She is flying, she is flying!!!!!! Sweet Lord this one has now turned into a ROCKET! At 1/3 Throttle she is ripping across my living room at breathtaking speed. I am ecstatic! I had never expected anything as fantastic as this to happen. I wish I could post a video but the speed is too enormous for me to handle indoors.  ;D

I want to express my deep gratitude to Mr. Musawir Mustafa, my guide and Mentor, who painstakingly helped me set it up from brushed to brushless. I couldn't have achieved this without him! :salute:

Outdoor land (maybe water) trials and video tomorrow! :thumbsup:

What a beautiful hovercraft {:)} {:)} {:)} :salute: :salute: :bow: :o.

Real screamer!!!Really noisy with the brushed motor ;D.If it does this with the brushed,I can't wait for the video with the brushless motor. 8-)  That would be some video.

Please post it at the earliest. (:|~ (:|~ (:|~

 {:)} {:)} {:)} {:)}  :salute: :salute:
Congrats VCji waiting to see the video .. hey even if its ZOOOooming past still u can load the video.. will give an idea of how fast it zips across or rather flies!!
beautiful build... {:)}

Here are some pictures of the model in new livery. The stickers were gifts from HobbyKing with a purchase (Coke from a local bottle!). The black stripes are made out of automotive dull paper.

I am seriously worried that she will flip over at half throttle. Planning to increase the weight by adding ballast to the hull. Any suggestions?

mpp, check out the earlier video and play it at 5 times the speed on GOM player, you will get an idea. I am NOT exaggerating. Will post a video tomorrow if the weather is conducive. Already looking for a large enough place to try her. Actual test will be on water. Wish me luck.

WOW..!! :bow: But still eager to see the New one.. the very best.. :thumbsup:  :thumbsup:

and i think there is simply no need to say what is very evident.. the build is fantabulous!! Cooolll.. Thanda matlab....  ;D

hey just wondering if "that" rip stop material could be used for the skirts  :headscratch: i still havent used it anywhere  :giggle: have something in mind but implementing will take some time.. you know!!  ;)

All the Luck  :thumbsup:

I used neoprene pipes that are used in Air conditioning and industrial refrigeration. I have some Rip Stop material and will be using it for subsequent builds, on larger models where the skirt will have to be inflated. I will then be using separate fans for lift and thrust. More on that later! :salute:

MPP, don't waste 'that' material on the skirts. It is precious  :salute:. I am saving it for covering the wings of an Inchworm glider in future. If you want to make a Hovercraft skirt, just buy a car cover (Rs.1000/-)  and it will be sufficient for 8 - 10 skirts for 1/35 Scale Hovercrafts.

"That" material is priceless, let us not waste it!

God bless!

VC

Wow, VC bhaiya i can't wait for a video. The craft looks beautiful. {:)}

Video uploaded. Shot in a rather confined space, judge for yourself. Max 1/3 Throttle with the Throttle trim at its lowest position. Need a football field for this!

Warning : Keep your speaker volume low. Jimmy was too excited!

http://www.youtube.com/watch?v=MmVWWOt6VGU

Awesome video VC. :) Great work there :)

nice build....great drifting an 360's

Great work, really good. Would love to see a test video on water. {:)}

Water trials were good but I have to add thermocole ballast for greater flotation. Modifying the hull / base now.

wowwwwwwwwww.................

it looks great and even hovers great!!!!!!!

 :thumbsup: :thumbsup:

its bit hovering.
but still wow as it is diy

Thanks Vineet (and all the others). I don't really understand what you mean by 'bit hovering'. I couldn't give any more throttle as she was flying out of control. In this case, higher throttle is equal to higher lift as we are operating on a single fan for lift and thrust. I am almost reaching aircraft take off speed here on 1/3 throttle. She must have been atleast 2 -3 mm clear off the ground to achieve this speed, or else the skirt would have been ripped to shreds.

If you mean that the nose is sticking to the ground, you are right! Rectified that by redirecting the airflow via a shield. Video on water follows, hopefully, tomorrow!

Cheers!

nice build VC sir :thumbsup: :salute:! i think cg is far front thats why its ratlling!

It handles like its on oil.But that is what you get on a hovercraft.They aren't meant for tight turns and stuff.Good video by the way.And waiting to see it on full throttle.If you've got any ideas to get it to handle better,let us know.I'd love to know the solution.This was said by Jeremy Clarkson on Top Gear,"In a hovercraft,if you see a tree coming at you,you are bound to hit it". :giggle: :giggle: :giggle: ;D

Excellent build vc........   {:)} {:)} {:)}

i think you got what i meant by bit hovering , u should use seprate motor 4 lift , just want to see working more realistic , loking forward video on water but i dont thing it can else your hovercraft is not genrating that much lift .

i think you got what i meant by bit hovering , u should use seprate motor 4 lift , just want to see working more realistic , loking forward video on water but i dont thing it can else your hovercraft is not genrating that much lift .

would be better if you can fabricate detachable wings - so it will be howercraft and plane :) Its just a thought. :)

WWWWooooowwww Fantastic VC Now on water :-)

Rajathv8: "would be better if you can fabricate detachable wings - so it will be howercraft and plane Smiley Its just a thought. Smiley"
+1 VC wishful thinking is good!!               :-D

First maiden on water with an improved skirt. it would have been better if the skirt was flexible and not rigid.

http://www.youtube.com/watch?v=rslE_ZydAe4

 :thumbsup: cool VC sir! Now I gotta go build one too. Guess crashes will be far less, being close to the ground with this one  ;D Great work Sir!
Edwin

Great work VC. Adding additional motor for cushioning will give excellent effect.  {:)} {:)} {:)}

Awesome build VC {:)}.
was wondering what is rip stop material ???

Thanks everybody. Will leave this baby alone as she is. She was an experiment and has been hugely successful in her own way. She has boosted my confidence for an ambitious project that I plan to take up now. In that project, I will try to incorporate the suggestions that you all have made. More on that within a few days.

Thanks once again!

VC

Rooster, I too am not sure what exactly Rip Stop is all about. I plan to use the material used for making car covers for making the skirts for my future projects.

Ripstop is just another name for the nylon fabric material used in laptop bags and good quality backpacks. It has nylon threads in a crisscrossing pattern that prevents it from tearing (unlike cotton fabric thats tears in a straight line when pulled apart)
Edwin

Where can one buy this from? Does it go by a local name?

Wouldnt that be a little too flowy to take the air pressure at the bottom. I mean the pressure needs to be held by the lining.Wouldnt some stuff like a bicycle tube would be pretty good for this purpose?

Shreekant

Rip Stop is the material suggested by almost all  RC Hovercraft modelling sites. Bicycle tubes will not lend a scale dimension. I am aiming for a near perfect scale appearance, as far as possible.

You could probably try a bag repair shop in your Area Sir. They must have the stuff or perhaps know someplace where it will be available. It goes by 'nylon fabric', 'parachute silk' etc.

Thanks a ton! Will start hunting tomorrow.

Dear VC,

Have you had any ideas with the airbags used in Printer toner packages?

They are pretty strong, specially the black ones and are like tubes which can be carefully cut to make a tubing.
You can then use cloth tape to cover it up completely, Cloth tape is like crepe bandage, but its stronger and does not wear out easily.
The final product after wrapping looks like the material which is used to make "dingy's"

-Dorwin

Hahaha...Am fed up of refreshing this page...
VC show us some action ;D

Ok Buddy, your wish is my command. I will have something worthwhile to post here another 30 mins from now.

 (:|~ (:|~ (:|~
 :thumbsup:

30 minutes up!!!  ;D

waiting.......

This is the first post that I am about to make about my most challenging project ever. I need the good wishes and guidance from all forum members to pull this one off.

My team and I are trying to build scale working replicas of 3 RC Hovercrafts. The Griffon 2000TD, Griffon 8000 and the LCAC 1 Assault Hovercraft. Each model is going to be approximately 4 feet in length and the LCAC 1 will carry a T 72 tank as a payload. Each model will not only have to be fully functional, it will also be detailed to scale.

So go ahead and wish us all the best. We need to complete this project by 31st. Dec 2010. Procurement of equipment has already started.

Best of luck VC bhaiya, hope that your project completes successfully and within the deadline(unlike our commonwealth games project).

Thanks!

Awesome!!
Go on!! no looking back now..you've come too far already ;D
hope you guys have decided which one to choose!!

All the best.Why do you have a deadline?

I wish I could explain that. but I can't.

" A dream remains a dream till you add a deadline to it. Then, and only then, does it become a GOAL. Dreams die hard, Goals can achieved."

  (As quoted by VC Sir. http://www.rcindia.org/rc-general-topics/if-your-wish-came-true/msg28058/#msg28058 )               

 {:)} {:)} {:)} :salute: :salute: :bow: :bow:

for better movement, you can add two turbine fans, that can brake fasterand rotational will be faster even static rotation will be possible.

elevators and rudder may lift to sky too.

Thanks.

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/

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 :Rs: 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 :hatsoff:

 {:)} {:)} {:)} :salute: :salute: :hatsoff:

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

How much do you want for the motors?

200/- per piece, all new condition...

Alok - Trying to call you but there seems to be a network problem. Pl post some pictures as I am interested.

Motor Pics...

Superb Build VC Sir..

I have decided to make exactly this thing but with restricted dimensions...

Could you please tell which propeller and battery have you used in the brushless setup....?

As you prefer brushed system over brushless in these ventures but I have two Turnigy 1650 bell type motors lying spare with 3s 2200 mah batteries.... Want to make use of it which will save me the cost of purchasing Brushed motors and brushed ESC's....

My dimensions for the craft should be within 40 x 40 x 40cm.... Please suggest propeller accordingly for high speed...

Thankyou...!!

1650 Kw should be plenty for a 6x4 prop, but again for a 40cm craft that will be an overkill. Too much power. Better go in for a 4x4 prop setup. Power draw should be less than 10 A in that case.

Is again 3s battery overkill..?

Should I purchase 2s?

Good idea! First check the performance with a 2S Lipo, if it needs more punc, you can upgrade to a 3S and I will buy the 2S from you.

How much mAh would you suggest as per its weight...?

2200 will be fine?

That will depend on the Amp rating of the motors and how much of a runtime you expect - if a single battery has to power both the motors for Lift and Thrust.

I intend to use only 1 motor as in the above craft by coro...

I want around 10-15 min of backup...

Later on in the next model I will upgrade 2 two motors...

Thankyou...

Well done again another great hovercraft

Nice and sleek looking

Thanks again!