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Nickinoue - n/a
16-Sep-08, 11:08 AM
Hi all,



Thanks for you assistance, i now have the skirt material on order.



The next thing to prepare is the template. I already have the original one that i made 6 years ago based exactly on the challenger skirt. As we all know this is a pritty shoddy design with problems with air leakage.



To improve this i am not using tabs on the corners, but instead am turning up the corners and using that as the loop for the zip tie.



I have uploaded a video on youtube: http://www.youtube.com/watch?v=EoDPiOXnAHY



of my initial design on a full scale but 1/8 section of my hovercraft powered by a fan, just to show what it looks like when inflated. It must be noted that this is an open section and all my sections on the real craft will be pressure or chipbags.



I was wondering if i could ask you for advice, and or improvements on manufacturing/designing the skirt.



The next question is to do with skirt top attachement. I am planning on having aluminium strip around the perimeter of the craft with the skirt material folded over the aluminium. The question is, do i use just spring clips or do i use that rubber edging, or even both?, some pics are attached below.

Sean Atterbury - n/a
16-Sep-08, 12:16 PM
I have found that the challenger skirts are as you say, a bit leaky, however I also found that by just making the skirt tight against the hull instead of those long attachment loops they work really well. Sure I had a plough in or two but that is now fixed with the new chipbags. They work wonders. I see you are making your own skirts, GREAT idea, I wish I had done that this time, I however had'nt got the proper sowing machine, so when I got my skirts back, the back ones were made upside down and the open Hole with drag flap over it was sown closed and the curve where the air is shaped down under the craft was open, as you can guess it all ended up as a big mess and another leason well learnt. http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif

Nickinoue - n/a
16-Sep-08, 01:18 PM
Doh,



It supports the learning by mistakes though!



I have a 1900's Singer sewing machine i picked up for 30 in a charity shop, it work so well an really nicely engineered, the only things is you have to be very good at multitasking as you have to turn the handel and feed the fabric in.....



Nick

tonybroad - n/a
16-Sep-08, 01:55 PM
use spring clips and the rubber edging



don't rule out just open segments it may be worth having some segments open at the front or alternate pressures and open so there is a good flow of air underneath the craft - only when you test will you notice



i use open all round and chipbags at the rear but the front can be a bit soft at times so i'll be introducing pressures

jon_curtis - n/a
16-Sep-08, 07:18 PM
my challenger, worked best with open segments down the sides, chip bags on the back, pressure segments on the front and a drag flap!



i would start with opens down the sides (it gets more air under the craft) after all you can always add them.



and the pressure flap as per the guide, does need to have the back edge tight agains the planning surface to work properly.



them old singers should sew it ok, i have me mums slightly newer elecy version, get some needles maid for denum, it should be ok.