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Winter
13-Apr-10, 08:25 PM
Hi there

Ever since I was teenage I've loved the idea of building myself a 3/4 seater cruising hovercraft. Although I had the space and some of the tools when I was a teenager, I never had the money. Now I've got the money, I live in a second storey flat so I haven't the space.. however the pull is still strong.

Long story short - I'm thinking it could be a good summer project to build something. I've no particular skills in joinery or mechanics - I can put up a set of ikea shelves - but life's all about learning.

Obviously, until I'm sure I'm going to be doing this, I don't want to spend too much money joining the club, but could I be cheeky and ask if anyone has any advice on good designs, or hints and tips before I get started looking for a suitably large lockup to build the thing?

I'm in Glasgow so if there are any local groups, I'd love to come and meet up - didn't see any on the map page but it's got to be worth asking!

Anyway thanks in advance for any and all helpful comments!

Ian Brooks
13-Apr-10, 09:47 PM
It is possible for a relative newcomer to build a capable 3/4 seater. It is a serious undertaking, and you can reckon on spending in the region of £3-5k along the way. You will need competent DIY skills, and may need to be able to locate help with some specialist areas such as welding, but much of what's needed can be learnt along the way.

I always recommend the Sevtec (http://www.sevteckits.com/sevteckits/sevteckits.htm) line of plans-built craft. There are several in the UK and they are very successful if well built. They supply comprehensive "how to do it" videos (at extra cost but well worth it) and when you join the Club, you'll find plenty of build advice on the website.

Ian

gavinparson
13-Apr-10, 09:53 PM
The £28 to join the club will be a drop in the ocean compared to the £3500 minimum it will cost you to build a large craft.
Building a craft that size is not something to go into without a lot of planning and advice. You need it to be safe and reliable as your life may depend on it. Also if it keeps breaking down you will get disillusioned and leave the sport.
Perhaps you're better off building a 1-2 seater craft first and then move to something larger when you've got a bit of experience under your belt.
I always advise people to buy a secondhand craft first and learn from it, but if you're adamant you want to build something then buy a decent hull and fit it out.
I'm sure the guys with Sevtecs will suggest you build one of those especially as there are guys up your way who own them. I think it's a lot of work for a newbie but you must do you research first and then make your decision.

Gavin

Jon Pert
13-Apr-10, 10:00 PM
Obviously, until I'm sure I'm going to be doing this, I don't want to spend too much money joining the club, but could I be cheeky and ask if anyone has any advice on good designs, or hints and tips before I get started looking for a suitably large lockup to build the thing?



I'll be honest with you, the club membership is the cheapest thing you will buy when wanting to build a craft. The information available in the member areas is worth it alone.

I would always recommend buying a good second hand craft as your first.

If you are not that experienced at building things then I would recommend it even more. By getting a good second hand craft you will have something that already works and then you can tinker with it and learn what makes them work and what doesn't.

However if you are dead set on building one then as Ian says the Sevtec (when built right, and slightly modded) work perfectly well in the UK, there are a few of the 'Sevites' up your way and I'm sure they'll be along soon. You could also look at the ASV plans, cracking craft.

Jon Pert
13-Apr-10, 10:01 PM
Bloody hell, me and Gav in 'type the same thing' shocker!!

gavinparson
13-Apr-10, 10:10 PM
Ooh spooky!

hector46
14-Apr-10, 06:41 AM
Come up to Loch Fyne at the end of May. You'll get the chance to see a range of craft. Build choice is limited to ASV, UH, K&M or SEVTEC. ASV wins on looks, SEVTEC wins on function as a cruiser IMO.

Try before you build !!!!!!!!


Steve

gaz
14-Apr-10, 07:26 AM
ASV wins on looks,

:D:D:D:D

http://www.hovercraft.org.uk/picture.php?albumid=33&pictureid=362


http://www.hovercraft.org.uk/picture.php?albumid=33&pictureid=490

Winter
14-Apr-10, 07:12 PM
Thanks, lots of information there!!

I think I mistyped what I meant to say, I didn't mean I wasn't going to join the club, just that I wouldn't until i was sure I had a viable plan. As soon as (If!?) I'm ready to pull the trigger on a project like this, it would be one of the first things on my shopping list for sure.

Maybe a 3/4 person is a bit adventurous - is it that much easier to build a smaller 2 seater one? The act of learning as I go along isn't daunting to me, but I obviously don't want to bite off more than I can chew.

Fitting out / modifying a hull sounds like an interesting idea.. the really arduous part of the building would already be done - that's definitely an interesting prospect - especially since I'd have to rent space to do the building, the shorter this phase can be the better!! Would the same be said of a kit? I've seen a few of these about, supplied either as patterns ready to be cut or even as almost prefab parts. Seems like an expensive way to do it though.

Loch Fyne would be interesting - especially if there are going to be a few different designs of hovercraft there, it'll be good to hear the pros and cons of each design first hand.

Thanks a lot for the information, I think I will modify my plans downward to a 1/2 seater then, and have a look to see what second hand stuff is about.

hector46
14-Apr-10, 10:33 PM
In reality there is not much difference in building a 1-2 seater or a 3-4 seater craft. Obviously it will cost a bit more and take a little bit longer to build. Decide what you want the craft to do, the odd couple of hours in the best of the weather here and there or longer distance cruising in occasionally more challenging conditions with a higher payload. Then buy or build something that suits those requirements. Bigger is usually better with hovercraft. Al Wilkins built a 16' Surveyor for his first build and seemed little daunted by it!!!! There are larger craft out there (BBV and Vortex to name a couple) although not quite so many plans for such at the moment. Hopefully see you at Loch Fyne.

Steve

gavinparson
15-Apr-10, 04:01 AM
. Bigger is usually better with hovercraft.

I disagree. Over the last 32 years I've had more fun with 1-2 seater craft than I had with a 4 seater.
The 4 seater I had took considerably longer to build and cost far more money to build than any other craft I've had.. Then you've got considerations such as storage, getting on and off trailers and often larger craft don't trim well when used one-up.I've also felt that larger craft don't handle chop and rolling waves as well. They can get stuck in the troughs whereas smaller, lighter craft will pop over the crests easier.
Also trying to rescue a big heavy craft way out on a beach or mudflat is a nightmare.

A 2 seater craft can be quick and simple to build, light and easy to unload and gives hours of fun. It's also far easier to rescue should anything go wrong.

Whilst I would consider having a larger craft again, I would have to seriously weigh up the benefits against the disadvantages.
You see quite a few 3,4,5 seater craft used with only 1-2 people onboard most of the time so perhaps the owners would be better off with a 2 seater in the first place.

atters
15-Apr-10, 07:02 AM
All true, but if I were you ( I am not ) I would do a small simple craft first, Integrated and square.

I am sure you could pic up a old used Vortex or Eagle 1 somewhere, if not then build yourself one of the clubs Challenger. ( thats how I got started )

I then chucked in a 503 and the craft was more to my needs, I am now building a Serveyor 16".

So as you get more and more into the sport, you will find your place and build or buy a craft that is for you. I love the racing and watch it on my laptop as often as I can, not being able to take part, but here in Africa a cruiser is what is needed, a small craft is fun but I had many problems with it in these conditions, ( Hover hight, range, ability to go through long grass etc ) I found myself fixing skirts and holes in it more than I was using it for fun.

just my 2 cents.

John Robertson
15-Apr-10, 10:01 AM
Robert,

You will get many opinions on which type of craft you should build and it is obviously up to you to make a choice. There is, however, one single thing that should override everything else and that's were and how you intend to use it.

You are fortunate to live very close to one of the premier cruising sites in the UK - the Clyde estuary. It has hundreds of miles of spectacular scenery and many lochs, inlets and rivers to explore. However, you will need a craft capable of safely handling the challenging conditions you are likely to come across in this area or you could get into serious trouble very quickly!

Become a club member and you will get access to our launch site guides - there is an excellent hovercraft launch site just outside Glasgow ;)

Conditions can change from this:

pXdjO_VJuVU

. to this:

Q8SgUrf11dk


... in a matter of a few minutes :eek:

In my view, if you want to to cruise in this area (and you would be mad not to want to :)) I would recommend a craft of at least 14ft (or larger if you can). The cost and build time over a smaller craft are negligible. There are good reasons why you don't see small (sub 12ft) boats out in the Clyde estuary!

To reduce rental cost, you could build all of the hull components first (rudders, engine frames, etc, etc) before starting on the hull (the big part).

Choose your location and purpose, look around for real-world evidence of craft operating in these conditions and then make your choice. If you have any doubts about anything then ask on this site - we are all here to help!

Ian Brooks
15-Apr-10, 07:45 PM
As ever, it's each to his own, but here's my personal view:

I had a 9' 6" Osprey first. I knew the first time I took it out into open water it was too small for my liking, so I took the rest of the season, looking at what everyone else was using & what was available. I happened to be in the US late in '05, and arranged to meet with Barry Palmer of Sevtec. One ride in his and I knew where I was going - The Surveyor.

Mines built to 14 ft, I often wish I had built it to 16ft. When you are out there in open water, 14ft is very small, and when you're facing 4ft waves you'll be glad of some structure around you. They have a clever skirt system that means they trim out well one-up to fully loaded, and I find mine easy to get on/off the trailer (although thats got a lot to do with the trailer design).

Just my thoughts...

Ian

Winter
18-Apr-10, 04:39 PM
After sleeping on it for a couple of days, and re-reading all the comments in the thread, I find I'm more confused than when I started :(

I think I would be using the hovercraft primarily for day-trips involving myself an one or two other passengers, maybe with a day's worth of provisions and then a few longer journeys scattered throughout the year. It's hard to judge, really, because right now I have no boat of any kind, so I have no pattern for usage. I don't think I want to race, but who knows if I get bitten by that bug things may change!!

I live in a city, with off-road parking and have a large hatchback car for towing a trailer, so if it was small enough, it could live on it's trailer under a tarp, where as something huge and unwieldy would mean renting a lockup on a permanent basis. Not ideal but liveable.

I've had a brief look on ebay, can't seem to see anything for sale there, are there any other places (other than the forum here and on ebay) that are worth looking at for places to buy either a completed second hand craft or the bits of one? The cheaper the better really, without wanting to compromise the quality of the craft at the end. I've also had a look at those sevtec ones on the internet - the bow section of the skirt reminds me of a frog's nose and throat. That's not to say it's a bad thing, just unusual.

Rest assured, when I'm sure this is a viable project and I'm going to start, I will be joining the club but until I'm sure it's worth doing, I'll hold off. Otherwise it seems like I'm joining the club to find out if joining the club is right for me - not really a good way to entice someone in!

As for coming along to Loch Fyne - that would be great, if it's not an issue to have a non-member showing up and asking thousands of questions I'd love to come along. There's a new addition to the family (nephew) due at the end of May though, so I hope that it doesn't clash!

Ian Brooks
18-Apr-10, 05:20 PM
To be confused at this stage is not surprising !!!

Your expected usage profile isn't too unusual, like many people at your stage you imagine taking the craft down to the local slipway and launching with perhaps one or two members of the family on board for a cruise. To achieve this, you need a minimum of a 14' craft - the Osprey, for example, is 9ft 6", a one seater and cramped at that.It's not really suitable for a day cruise.

It is quite unlikely that anything useful will come up on ebay. Lots of small craft come up, none of these are suitable for your usage, and most are only suitable for using in the paddock. Be careful and ask here before you bid, but expect to pay serious amount of money for anything worth having - in excess of £4k for something needing some work, more like £6-10k for something which is 100%, and such craft come up for sale very rarely.

Ian

Winter
18-Apr-10, 07:22 PM
Where would it be best to use a smaller hovercraft? Are they really only suitable for land use, or flat water? I ask because as I said, I live in the middle of a city - no land of my own. I wasn't thinking about making any huge sea journeys with it :)

hector46
18-Apr-10, 08:32 PM
Winter (what's your first name?)

I lived near the Clyde until a year ago. I have taken my hovercraft from Port Glasgow to the middle of Glasgow five or six times. I've also taken it up Loch Long, Gareloch, Holy Loch, Great and Little Cumbrie and up river towards Paisley (the Cart) and also up river towards Loch Lomond. I don't claim to know the area like someone who has lived and worked on it all their lives but I can say I know, love and respect the area a lot. You are a lucky lucky lucky potential hovercrafter. I would move back in a minute if it were possible (apart from the precipitation, it does rain a lot). I would take a smaller hovercraft with good freeboard up the Clyde where it is more sheltered. I would not take a smaller craft anywhere else on the estuary or lochs. The conditions change so quickly and so often, you IMO should not consider anything less than 14 feet. You, your two passengers and gear (you'll need more than a rubber ring and some snickers bars) plus contingency dictate that a slightly larger craft is required. This a fact and not opinion. My next build is 14 feet and the one after is going to be16 feet. This suits my needs and the sea and weather conditions I've experienced. Also for me the difference between building a 12 foot or 14/16 foot hovercraft is so small and not worth being concerned about. I have never been hovercrafting and thought I could do with a smaller hovercraft but can say I've thought I could use a wee bit larger one on several occasions :)!!!!!!
You should join the club, it will provide you with a lot of relevant information that will help you make a decision and it costs pennies in relation to the cost of a build or buy. You will get you monies worth out of it, and they even value your Scottish pound as a pound when you join, not bad I say !!!!!!!!


Steve

Brian G. Reynolds
19-Apr-10, 07:50 AM
Hello "Winter" you know you want to.... come on joint us and never have any money again!!!!

I am planning of attending the “Scottish” event as I have seen a lot of their video’s and it looks massive fun up there!

I will be bringing my 16.5 foot Osprey 5 which I love! I have lots of images of it on my website, follow the Hovercraft links…

www.Reynolds-Towers.com (http://www.reynolds-towers.com/)

It is meant to be a 5 seater and I have had 2 adults, 2 almost adults and 2 10 ish year olds in it and it did get over hump! But only in ideal waters inland…

I expect to have spare seats so if you pop over you are more than welcome to join in the fun.

B.

Winter
23-Apr-10, 05:32 PM
I've noticed that one of the commonly used materials is a kind of foam board that (looks like!) it's fairly easy to work with, and has good strength vs weight, but is quite expensive.

I might be able to get hold of aluminium honeycomb for a reasonable price - basically it's a 0.6mm thick skin of aluminium, then a framework of tiny honeycomb, and then another skin of aluminium. I've seen it used as flooring material, it seems to have really good strength and it's very light too. I'm getting a bit sent to me so I can work out the weight if it was in a bigger sheet - has anyone here used that type of material? I can basically get it for a bulk suppliers cost, because they'll order me a few extra sheets when they're buying hundreds at a time, and they might even cut to a pattern for me, so providing it's going to be at least as strong as that foam board and no heavier, I'm thinking it might be a good way to go.

Any thoughts on using aluminium in this way??

pest619
23-Apr-10, 05:51 PM
Ive been using some half inch thick alu honeycomb like you describe and they are using it on Griffon craft as decks, walls etc. It may be slight overkill to build a whole sev craft out of it- they only problems are the weight and how you join the seams- must be glassing or riveted sheets of alu as there is glue attaching honeycomb to skins.

Winter
23-Apr-10, 06:46 PM
Well, I was thinking more of using it on some sort of frame to be honest, and probably riveting it on, although that obviously depends on what the frame is made of.

If you did that, could the seams / joins between the panels be fixed with something like silicone or something like a marine version of bathroom sealant? - it wouldn't need to be structural, just watertight, since the stresses would be all in the framework.

Is it a lot heavier than the foam boards? I'll be able to weigh some soon when it arrives midweek.