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Ukraine Train - n/a
20-Nov-06, 07:55 PM
Hi everyone,



I've decided to try to build a hovercraft but I'm having trouble finding some information. What I have right now is a 22hp vertical shaft 4 stroke engine. I want to keep this a low budget project so I want to use this engine for both lift and thrust. I have an electric clutch that's used to engage lawn mower decks with the push of a button. I think I could use that to engage the thrust fan. My big questions right now are, what materials can I use to make a skirt and what can I use for lift and thrust propellers on the cheap? For lift I was thinking of using an impeller from a leaf blower like shown below but from my calculations I can only get about 30CFS with one, I'd need about 60. Has anyone used one of these successfuly? I'm in the US, so I'd like to stay with domestic vendors. Thanks for any help.

http://images.amazon.com/images/P/B0002IKVZ4.01.LZZZZZZZ.jpg

Ian Brooks - n/a
20-Nov-06, 08:06 PM
Hi



Cheap propellers and fans are probably not a good idea... but a good set of plans will pay for themselves many times over! Such as this, which will work very well with your engine and can be built on a budget:



http://members.aol.com/sevtec/sev/SCOUT.html



Or maybe a UH model, I'm not so familier with them:



http://www.hovercraft.com/content/index.php



Cheers

Ian

Sean Atterbury - n/a
21-Nov-06, 05:21 AM
AGREED !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



Trust me, get a set of plans and follow them as much as is possible with what you can get your hands on.



It took me 4 years, and I had plans, I however could not get the propper materials and thus spent a fortune and in the end had to get parts custom built to get the craft running propper.



With that motor I would go simple and single fan, integrated craft, direct drive, no clutchy thing, keep it simple and easy, it works out better in the long run.



Well that's my 2cents.



Use it or not, its up to you.

jon_curtis - n/a
21-Nov-06, 09:47 AM
22hp is not a lot at all to go intergrated!



the picture is that of your engine? as it looks horizontal not vertical???



why not have a look at the sevs as per ians, links. the hulls are very quick to build and dont cost the earth. with a small ducted fan for lift and a prop for thrust, you would get the most out of that 22hp.

Ukraine Train - n/a
21-Nov-06, 12:32 PM
Thanks for the replies. Sounds like working from plans is the best route. The picture I posted just shows the type of impeller I was thinking of using to create lift.



Atters, were you saying I can use a single fan for both lift and thrust? How does that setup work? Thanks.

Don83000 - n/a
22-Nov-06, 01:01 AM
Try here also just click on plans / kits



http://www.hovercraftersresource.com/plans-kits.htm (www.hovercraftersresource.com/plans-kits.htm)



Also check out some of the video's etc on this site the small craft was using a 13.5bhp motor but has now been upgraded to I think 22bhp it tells you in the info



http://www.hovercruiser.org.uk

Sean Atterbury - n/a
22-Nov-06, 05:49 AM
Yip Don has it all there, and he is the man who can help when it comes to props and ratios and drive and well anything, there is nothing that beats experience and he has plenty.



The single fan principle is that 1 third of the air created by the fan is directed down into the hull for lift and the rest is used as thrust.



Both ways have advantages and disadvantages and it is all down to you, what you want.



I have not tried the seperate lift yet but want to some day, but what I like about the single fan is; Pull and Go...



Instead of Pull and Pull and then only go... Less hasle I think, but with two motors then you have a permanent cushion and that for cruising could be quite nice, I realy struggle sometimes with that, craft bottoming out and bouncing around while I try find the right revs to keep it in the air and not move to much.



But it's up to you which way you want to go.