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Ashwin Murali
9-Feb-10, 03:48 PM
Hi all,

I have a couple of questions which i am sure you would be able to answer.

1. I'm using styrofoam sandwiched between ply sheets for the hull of my craft. The foam that i bought seems to be quite soft (I'm able to press it with my fingers). I read somewhere that such foams can be strengthened by applying some epoxy resin pastes. Is that advisable? If yes, suggest what paste should be used. Or tell me if its not a problem to use the same foam without any modifications. Also tell me what sort of glue should be used to stick the ply and the foam.


2. Is it ok to use tube rubber for the skirting considering that mine is a bag skirt? Also should the skirting be given for the entire bottom area of the hull of the craft or is it enough to provide the skirting only along the corners, leaving the bottom centre area without any skirting?

curtis5420
9-Feb-10, 07:40 PM
your going to end up with a total waste of money and time, that does not work!

but there you go!

solvent based glues will melt the foam, use either pva wood glue or epoxy. the foam will gain its strenght by gluing the ply to BOTH sides of the panel, one side is no good, it will be very strong once wood glued each side, but ensure the entire surface area of the foam bonds to the ply.

the skirt should go all around the craft, not sure what your trying to ask.

Ashwin Murali
10-Feb-10, 03:53 AM
@Curtis: I'm sorry. I didn't get you. Whats not going to work?

Yeah, i'm gonna use ply sheets on both sides of the foam.

Is the tube rubber used in vehicles suitable for skirts?

My second question is that should the skirting be provided in the corners like in the first pic or the entire bottom area like in the second pic (Note: The blue area is the skirting)?

http://picasaweb.google.com/ashwinmurali1988/Hovercraft#5436472650017933794

http://picasaweb.google.com/ashwinmurali1988/Hovercraft#5436472654911371762

Jon Pert
10-Feb-10, 08:03 AM
Skirt goes around the edge otherwise you would be driving a mattress! ;)

http://i41.photobucket.com/albums/e253/sixpackpert/conair.jpg

Ashwin Murali
10-Feb-10, 10:26 AM
Thanks a lot Pert. Thats exactly what i wanted to know.

hector46
10-Feb-10, 12:08 PM
You should use heavyweight PVC tarpaulin 600gsm or lorry curtain sider material 900gsm. rubber sheet with no fabric middle layer won't work.

Steve

PS That's an impressive hover height Jon!!

Jon Pert
10-Feb-10, 12:31 PM
PS That's an impressive hover height Jon!!

Yep, Conrad Beale wringing the neck of Jamie Lewendons old F3 Storm at Black Ditch some years back. Great transition that was, shame we lost the site.

24YwvfokxJU

Ashwin Murali
13-Feb-10, 06:55 AM
@Jon Pert: That was a wonderful pic. I could clearly see the skirting, but where are the holes through which the air escapes and causes the craft to hover?

broad5186
15-Feb-10, 07:44 AM
i'm no expert on bag skirts preferring segmented skirts but the holes are just inside the 'lip' of material where the skirt contact point is, you can see a jet of spray coming from one of them near the front, not all bag skirts have this lip but the holes must be inside of the skirts contact point

good luck

Ewan Black
15-Feb-10, 04:55 PM
The Vortex skirt, as in the pic has a "contact strip" around the edge, some of the air (for point of run lubrication) comes out of feed holes just inside the contact strip. The rest of the air (as for most bag skirts) comes out of a series of quite large holes on the inside of the skirt as high as possible.