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Ashwin Murali
22-Dec-09, 03:54 PM
Hi friends, i am about to begin my project - Hovercraft. What material is used for making the hull? Suggest the most suitable and economic one considering that i plan to build a single seater hovercraft with a payload of about 150 kgs.

broad5186
22-Dec-09, 07:08 PM
hi -

a bit more information would help us advise you, what do you intend to use it for i.e. racing, cruising/sea just for pleasure or the challenge of making one and what sort of budget did you have in mind, any engine thoughts ?

craft can be made from plans wood or fibreglass - just tell us a little more about what you'd like and we can give you best advice

Tony

curtis5420
22-Dec-09, 09:30 PM
i have made craft using the following:-

plywood and taped glass seams, can be heavy if not done right and does not have the longevity of grp.

aluminium alloy sheet, can be very expensive to get folded punched etc etc but strong and easy to repair, dents easily lol. but looks nice :)

foam core sandwhich, very strong, easy to build, not cheapest and poly resin smells.

foam core can be done with epoxy resin, but is more expensive compared to polyester resins.

got half way through making a rigid inflatble craft, and am now working on a grp mould :)

i would pic ally again, if i had facilities to work it. smells the least and gives the most impressive finish.

second choice, foam core sandwhich :) i just cant get enought of that sinking poly resin. working on moulds is very hard work!

Ashwin Murali
23-Dec-09, 06:34 AM
Since this craft is for college project, my aim is simple : it should hover successfully and move forward (need not be very quick). I initially had the idea to use plywood for the hull but some doubts crept into my mind. Now that i see you have mentioned plywood, i am inclined to go for it for it is the cheapest and suits my budget. Fiber glass is way beyond my budget. How thick should the hull be for the mentioned payload? 1 inch seems too thin and 2 inch seems too thick. Will 1 and a half inch be optimum? Also will a power of 7 hp be enough to hover the craft of size about 4ft X 7ft for a payload of 150kg (including the craft)?

pest619
23-Dec-09, 10:37 AM
Hi there,
do you mean a total weight of 150kg inc. driver? If so it would be possible to make a craft of the 7' x 4' footprint you describe, however depending on what sort of machine you make it may be very hard to keep the total weight below 150kg. Highly developed racing designs are at least around 200kg total weight.

If you aim to build a hull like the challenger hovercraft you want 4mm ply (i built one from 6mm but it was way too heavy). Or if you want to make a flat sheet leafblower type hovercraft like you see in loads of youtube vids (http://www.youtube.com/watch?v=TcCOdl-CrP8) you probably want one sheet of 12mm ply.

Pete

Ashwin Murali
30-Dec-09, 06:48 AM
@Pete, Curtis & Tony: Thanks a lot.
Now i've decided to use plywood. I'd like to know if plywood can be used alone or should it be coupled with some other material. I came across Styrofoam being used for Hovercrafts. Can styrofoam be used alone? Is it more suitable for Hovercrafts than ply? Should styrofoam be used in combination with ply? Also i'd find it difficult to get styrofoam as it is not as readily available as ply. Please suggest the most suitable option. As i had already mentioned before, mine is a 4ft X 7ft craft with a payload of about 150 kg (including the driver).