Cheque Book racing

Footy Class General Discussion (Footy)
1

Hi, I’m new to Footies but I do have a fair amount of experience of full size high performance yachts. Can someone help me?

I am building a home-designed Footy. I also have a good, reasonably well paid job. To me it is quite obvious that (if I am prepared to rake the trouble) I should use a carbon tissue/epoxide hull with an ultra-lightweight balsa core, tapered carbon tube mast (the model airraft people will sell be a 5.5 mm tapering to 2.8 mm tube with a wall tickness of 0.75 mm ex-stock), etc.

I must admit I did blench a bit when I investigated a titanium rudder stock (about ?90 = $180) but otherwise the materials are objectively quite cheap. The carbon tissue, for example, is about ?4/$8 per square metre which gives you enough for about 10 Footis, assuming no wastage. 1000 m of 10 kg breaking strain Kelvar twine is expensive in first cost (about ?9, $18) but must be pretty much a lifetime supply. The carbon tube for the mast is about $4/$8.

I do not know whether Bombur will work - the design is extreme in any ways and may be horribly wrong. It may also be that I do not have the skill in my hands to use such high-tech materials properly in very small sizes. However, I will more or less guarantee that I will have more ballast and sail-carrying power available than most of the boats described in this forum - which has to be a good start.

I have no inhibitions about taking more trouble over the construction. It seems to me that if I am preapared to take a few weeks to build a hull, it is quite fair if I have an advantage (dream on) over someone who does the wole hing in a few hours.

However, are such high-tech materials ‘cheque-book’ racing? I don’t think so - the quantities involved are so tiny that the absolute cost is tiny.

But what does anyone else think?

Angus

2

Development class - go for it !
:smiley: :smiley: :smiley:

3

Hi Angus, welcome to Footys.

IMHO, exotic materials are overkill. I can build a balsa or glass hull so close to the same weight that it doesn’t seem like carbon or kevlar would be much of an advantage, and I find glass easier to work with.

But everyone has their own preferences, so if you like it, go ahead and do it! Niel built a beautifully crafted couple of carbon-fiber Footys.

Whatever you decide, post some drawings of your design and pics of your progress. Sounds like you are thinking “out of the BOX.” :smiley: :smiley:

Bill H

4

If you feel like putting that much in materials and think that you can come up with a great boat. Go for it!!!:smiley: I do suggest, tho, that you include some floatation in your plan. I have found that it does not take much to sink a Footy:mad: (recovered it tho). I had to have a boater recover one my boats today when the wind picked up to about 40 today.
Bob

5

If there were an advantage to using carbon/balsa, or just plain carbon for hull panels, then I think it would have been tried straight away. We’ve discussed using carbon fibre panels before, but I don’t think anyone has had the courage (or finances) to try it. I think the Footy concept is just too small, at 300mm, to make use of the lightness or strength of carbon or any other exotic material.

When you mentioned Checque book racing, I thought that you were wanting to assemble the best of the pre-built boats.

6

Initial response to my question is interesting.

Most answers centre on whether hi-tech materials are of any advantage. I take the point exactly. With a structure as small as a Footy it is difficulty not to make the thing excessively strong no matter what materials you use within reason. 25 years ago I built an IOR half-tonner (LOA 30 feet) with a 12 mm balsa core with 75 g/m2 of S glass inside and out. The boat is still around and is widely regarded as being built like a battleship. Scale the thing down to Footy size using an elastic tape measure and we get a 1 mm core and 2.5g/m2 of S glass - and I am using 4 g/m2 of carbon tissue because it is the lightest I can get hold of and I cannot find any glass tissue that light. The true strength calculations make the Footy even more over strengrh.

Indeed, if the hull of Bombur is sufficiently fair, I am contemplating using it as a plug to make a single skin epoxide + kitchen roll hull just to prove the point. In the current version the wood core is there at least as much for ease of manufacture as anything else.

But that is not the point. I use the thoughts on materials that spring automatically to my mind to address the ‘cub scout’ or ‘bits I’ve got under my bench’ arguments. Are we trying to produce a racing class (and there is little point in it’s being an international class unless the intention is to race) that frowns on high tech and expense? Pesonally I do not think so. I do not think it is realistic to expect a cub scout to produce a competitive boat in any material - intelligent teenager, yes, but that is another matter economically. As far as the bits under the bench school are concerned, I can spend money on beer MUCH faster than I can on Footy materials - or at any rate in incorporating them into a boat. If the challenge is to build the boat as quickly or cheaply as possible, fine. But you should not sneer at those who want to go as fast as possible.

Back to you gentlemen and ladies.

Angus

7

Go for it Angus,
Where do I get 4gm2 carbon tissue:)

8

Woops - senility strijes again. It’s 16 g/m2. Sorry.

A.

9

ok then,
Where do I buy 16gm2 carbon tissue??
attached pic is my new hull plug…aka cheque book arms racer:)

10

Hi Brett
www.freefllightsupplies.co.uk.

He’s a bit erratic - strictly a part time one-man band and I think he’s on holiday at he moment!

A.

11

I’d say you’re welcome to use whatever you like for your own personal pojects, but if you want to use glass or carbon tissue(s), why not make a mold nd use the tissues to make a hull from the mold? It would be easier to build and probably even lighter than incorporating any balsa into the hull whatsoever.

I’m only using the glass tissue on the outside of the hull for waterproofing, not really for strength. I don’t even use epoxy resin- I use polyurethane resin.

12

Thanks TomoHawk. That was more or less what I was thinking of - I get two hulls for little more effort than for one - and damn all extra cost. There is a slight problem. The Bombur design has rather pronounced tumlehome. Mouuld the kitchen roll hull in two halves and glue together>

A.

13

Angus, if you feel carbon gives you a competitive advantage, go for it. I expressed my opinion that it’s overkill, but it was only an opinion, and no sneer was intended at all. In fact, if you convince me that I can build one significantly lighter with carbon than I can with glass, I’m sure I’ll switch!

My concept for the Footy class embraces those like you, Niel, and Brett who want to push the limits for serious racing, but it includes the Cub Scouts, too. I don’t think they are mutually exclusive. Rather, I see them as two sides of the same coin.

It’s likely that a Cub Scout would be unable to build a competitive boat for serious racing against you guys, but chances are that’s not the Cub’s main interest. I’ll bet a Cub can build a Footy that’s competitive with the other Cub’s in his Pack, and racing against his buddies could be enough to get him started in this great sport. One or two of those cubs just might grow up to be as serious about racing as you are.

If we target the class at only serious racers, I think we become just another high-tech racing class. There’s plenty of those to choose from already. But how many Dad’s can take a Saturday off from racing their USOM or 36/600, build one with their son or daughter, and go sailing together the next day? You can do that with Footys.

I believe there’s room in the class for all levels of enjoyment. The rules are simple enough, and boats can be built cheaply enough, for Scout or family fleet projects, yet they still present a great deal of latitude and challenge for serious designers. That provides an opportunity to get young people involved at a low cost of entry, then encourage them to develop their understanding and the sophistication of their boats as they grow older…all in the Footy class! It also gives you serious racers the opportunity to be the leading edge of the class, and I hope, the mentors for those young future designer/racers.

IMHO, that’s pretty neat, and it’s something that makes Footys really special.

Bill H

14

Thank you very much: that is much what I hoped people would say.

My interest in this started out as a challenge to try to pass some of our family tradition of boat building and dsign down to the last male Richardson who is 15. Design it, build it and race it against your wicked uncles! Cash prize for winner.

I have deliberately not tried to encourage him to sdopt a low tech approach. Unless something goes horribly wrong, he will live his life in a world of exotic materials and automatic acceptance of technologies that are not far removed from a WW I biplane does not seem a good idea.

I take what you say about high tech materials though - or partly. I am currently confined to bed so my use of this fascinating site over the last couple of days has been considerable. I am rapidly revising my views on how light lightweight structures can be at this size. It is not that the hi strength materials don’t work - it’s just that there is a fearful tendency to make the result MUCH too strong.

A.

15

Footy does indeed appear to be… ‘a boat for all seasons’. This is a very interesting conversation Angus, good to have you here. I certainly echo Bill H’s overall view of the Footy class, there is no doubt that it’s small size catches the attention. I had the chance to hand the transmitter for my Kittiwake around to anyone who wanted it at a recent local regatta… the result was lots of smiles and some surprise at it’s ability to actually sail properly! It makes friends easily you might say.

Yet it also has such fascinating potential for development. I agree with you Angus in that such a small amount of material is required that actual costs per boat are small (titanium excepted) so we can afford to experiment.

Very nice looking hull Brett… really nice!

Graham

16

You might check out this thread in a different forum:
http://www.rcgroups.com/forums/showthread.php?t=523939
Boby built a footy using carbon – looks pretty good.

17

It’s about time, and I’ll bet that it’s really stiff. Let’s see what Angus will come up with now!..

18

That does indeed look impressive - and by the tone of it is an enthusiastic teenager, unless I get American nuances wrong!

More power to his elbow.

A.

19

Pure New Zealand Angus.

20

OK - yet another barand of ex-colonial. :slight_smile: :slight_smile: :slight_smile: :slight_smile: