JimC
Not actually an anarchist.
Especially as you'd have to add corrector weights if it brought the boat below minimum weight.So for every 100 l internal volume you could "save" about 100 g... That's disappointing...
Crazy Dinghy Ideas
- Thread starter Foredeck Shuffle
- Start date
martin 'hoff
Super Anarchist
Tie the big parade balloon top of mast...
Consider the hobie top of mast float as precursor...
Consider the hobie top of mast float as precursor...
Foredeck Shuffle
More of a Stoic Cynic, Anarchy Sounds Exhausting
- Thread starter
- #24
Oooh, so I have floaters on the 29er I'm playing on, if I filled them with hydrogen I could improve their buoyancy by 3.6g.
mckenzie.keith
Aspiring Anarchist
Helium fire extinguisher went off accidentally after the race started. That is not cheating, is it?
mckenzie.keith
Aspiring Anarchist
Realistically, for a mast with stays, yeah for sure. But in theory, if the inside is pressurized high enough and the diameter is large enough, the closed off ends will be trying very hard to get away from each other and this could keep the entire tube in tension when it is just sitting there, couldn't it?
The Q
Super Anarchist
Many older classes that you sit in not on, have buoyancy bags.. perfect for filling with helium..
Dart96
Member
McKenzie said:
" if the inside is pressurized high enough and the diameter is large enough, the closed off ends will be trying very hard to get away from each other and this could keep the entire tube in tension when it is just sitting there, couldn't it?"
That's a good summary. I've been thinking of where else do you find long thin pressurised cylinders? Can only think of aircraft fuselages at the moment. They undergo twisting and bending, so maybe the maths to analyse them could be extended to the pressurised mast idea?
" if the inside is pressurized high enough and the diameter is large enough, the closed off ends will be trying very hard to get away from each other and this could keep the entire tube in tension when it is just sitting there, couldn't it?"
That's a good summary. I've been thinking of where else do you find long thin pressurised cylinders? Can only think of aircraft fuselages at the moment. They undergo twisting and bending, so maybe the maths to analyse them could be extended to the pressurised mast idea?
El Borracho
Verified User
Yeah, thought provoking. Simply determine if your mast member is isotopic or orthotropic then digest this simple research paper and you will have your answer…
Foredeck Shuffle
More of a Stoic Cynic, Anarchy Sounds Exhausting
- Thread starter
- #30
Let's stay with hydrogen, better numbers. I could not find the cost of helium versus hydrogen but I'm guessing with global helium shortages and so many efforts to make hydrogen a commercial and consumer fuel it will be less expensive now and into the future. So blow up those bouyancy bags and hulls with hydrogen.
Hydrogen density at 26 degC and 1 bara:
0.081 kg/m3
0.00506 lbm/ ft3
0.000676 lbm/gal(US liq)
0.1571x10-3 sl/ ft3
Hydrogen specific weight at 26 degC and 1 bara:
0.794 N/m3
0.00506 lbf/ ft3
Helium density at 26 degC and 1 bara:
0.1602 kg/m3
0.01 lbm/ ft3
0.001337 lbm/gal(US liq)
0.3109x10-3 sl/ ft3
Helium specific weight at 26 degC and 1 bara:
1.571 N/m3
0.01 lbf/ ft3
Foredeck Shuffle
More of a Stoic Cynic, Anarchy Sounds Exhausting
- Thread starter
- #31
What ever happened to this? I'm guessing it was great in light air and perhaps not as much in heavy?
Steam Flyer
Sophisticated Yet Humble
H2 and H3 are easy to make. All you need is a source of DC current and a funnel.
Keeping it where you want it, that is the more difficult task. It will seep right thru almost anything that is "airtight." I handled elemental hydrogen as an industrial gas and it's the devil even without the explosion thing.
Keeping it where you want it, that is the more difficult task. It will seep right thru almost anything that is "airtight." I handled elemental hydrogen as an industrial gas and it's the devil even without the explosion thing.
nota
Anarchist
balloon airfoil shaped kite floated by H2
no mast no flip cat/kite boat
yes H2 leaks out of anything
but as water is H2O you have an unlimited supply
just move to spin a prop to make el tricks to get H2 free
pump into a gas tank for later use
my crazy idea
no mast no flip cat/kite boat
yes H2 leaks out of anything
but as water is H2O you have an unlimited supply
just move to spin a prop to make el tricks to get H2 free
pump into a gas tank for later use
my crazy idea
nota
Anarchist
side idea
if the super strong line had a shape
like a airfoil 1000ft long to the balloon
how thin can a foil be ?
foam inside a super fiber skin ?
if the super strong line had a shape
like a airfoil 1000ft long to the balloon
how thin can a foil be ?
foam inside a super fiber skin ?
Sorry I read about it a long time ago and cannot remember exactly what the article said. I believe the bow was closed later on.
The only thing I could find now was this:
The flaps at the bow on the other picture are also interesting
I would think, that in light airs it would not make a lot of difference unless you try to move the weight forward to reduce wetted area at the transom so much that the hole becomes immersed. Then it would create a lot of additional drag...
In heavy airs the extra water sloshing through the cockpit would be extra weight and make the boat less stable I would guess...
Dex Sawash
Demi Anarchrist
^ maybe with careful rocker distribution, the surge of water through the inside could become propulsive (if that's a word)
The Q
Super Anarchist
I saw that dinghy and kept thinking of" the Herald of Free Enterprise" all that free water sloshing about...
As I am lazy AND cheap, I would like to see some new building methods "IKEA style" without glueing/sanding for a proper doublehanded dinghy.
Maybe from materials like these?
www.display.3acomposites.com
A German sailing magazine published a huge story about the IKEA dinghy "Seglar" but it turned out to be an well prepared april fool joke.
Maybe from materials like these?
DIBOND® | The original aluminium composite panels
www.display.3acomposites.com
A German sailing magazine published a huge story about the IKEA dinghy "Seglar" but it turned out to be an well prepared april fool joke.
JimC
Not actually an anarchist.
There have been some odd Nationals. There was one at the dinghy show one year that looked as if a snake had swallowed a selection of geometric solids: lumps and bumps everywhere so as to hit every measurement point but have the bare minimum of boat between. Its debatable whether rule writing is a sufficiently precise art that the measurement points are all that critical.
martin 'hoff
Super Anarchist
3 silly ideas.
Pump a Tiwal 3 with helium. A proportion that's calibrated to the sailors weight and overall "all up" weight? If you capsize and lose the mainsheet, you'll have to go catch that stray balloon with a helicopter. Lol.
Screw in a lifting foil from a wingfoiling board – some of those boards are inflatable thanks to a rigid "box" where the foil screws in - so "splice" such a box where the daggerboard trunk is now.
Add a T rudder - or just a long rudder. The wingfoiling foils have a canard setup already.
Ride height control via "weight shift control" (WSC) as done on airliners. The wingfoiling kits with canards are well designed to control ride height with weight/balance. There's no "active" flap – this is way simpler/cheaper/sturdier than a moth/wazsp/ufo foil. They are surprisingly sensitive to operator movement.
Ok, so then how about a moth-like sprit and "wand" with a weight that travels fore-aft – in a "perfectly lubricated tube" – to control pitch and therefore ride height. The sailor still leans aft for takeoff, and might need to scuttle around a bit, but the wave-by-wave action is handled by WSC.
(If it helps, WSC is also how hang gliders are controlled.)
Pump a Tiwal 3 with helium. A proportion that's calibrated to the sailors weight and overall "all up" weight? If you capsize and lose the mainsheet, you'll have to go catch that stray balloon with a helicopter. Lol.
Screw in a lifting foil from a wingfoiling board – some of those boards are inflatable thanks to a rigid "box" where the foil screws in - so "splice" such a box where the daggerboard trunk is now.
Add a T rudder - or just a long rudder. The wingfoiling foils have a canard setup already.
Ride height control via "weight shift control" (WSC) as done on airliners. The wingfoiling kits with canards are well designed to control ride height with weight/balance. There's no "active" flap – this is way simpler/cheaper/sturdier than a moth/wazsp/ufo foil. They are surprisingly sensitive to operator movement.
Ok, so then how about a moth-like sprit and "wand" with a weight that travels fore-aft – in a "perfectly lubricated tube" – to control pitch and therefore ride height. The sailor still leans aft for takeoff, and might need to scuttle around a bit, but the wave-by-wave action is handled by WSC.
(If it helps, WSC is also how hang gliders are controlled.)
