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Ply-foam-ply Streaker? |
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Solo4652
Groupie Joined: 08 Apr 15 Location: Stockport Online Status: Offline Posts: 71 |
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Topic: Ply-foam-ply Streaker? Posted: 01 Nov 15 at 4:20pm |
I know that Gosling has made Solos with some sort of ply/foam/ply sandwich. Would this material work for a Streaker? Building a Streaker down to weight (48 Kgs) might be easier with this stuff compared to using traditional ply sheets, maybe? Would this material be stiff enough to do away with a double floor, thus giving more cockpit depth? What about the cost, compared to all-ply, or all-FRP? Just looking for ways to make it easy quick and cheap to build a new down-to-weight Streaker.
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JimC
Really should get out more Joined: 17 May 04 Location: United Kingdom Online Status: Offline Posts: 6649 |
Post Options Quote Reply Posted: 01 Nov 15 at 5:08pm |
I suspect that its not a particularly light form of construction, because the ply skins each side need to be strong enough to put up with whatever bad treatment they'll get, which means at least 3mm and probably 4mm. Be Barking stiff though.
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Solo4652
Groupie Joined: 08 Apr 15 Location: Stockport Online Status: Offline Posts: 71 |
Post Options Quote Reply Posted: 01 Nov 15 at 7:00pm |
OK - apart from really exotic carbon/nomex and similar, is there some other composite material that might work? What's the stuff that caravans are made from, for instance?
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JimC
Really should get out more Joined: 17 May 04 Location: United Kingdom Online Status: Offline Posts: 6649 |
Post Options Quote Reply Posted: 01 Nov 15 at 7:46pm |
If you're building a foam sandwich boat you can use any combination of fibres you like (rules permitting). Bi-axial glass is a reasonable combination of weight and cost for something that's not too challenging on weight like the Streaker.
To a good extent the issue with all foam dinghies isn't so much stiffness and strength, but having enough meat in the skin to put up with ham handed handling without denting too much (henceforth to be known as the shingly issue). |
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Paramedic
Really should get out more Joined: 27 Jan 06 Location: United Kingdom Online Status: Offline Posts: 929 |
Post Options Quote Reply Posted: 01 Nov 15 at 8:25pm |
The ply skin used to build solos is 1.5mm (Probably just a veneer in actual fact) and is decorative, not especially structural. I would think that the mock wood Phantoms and Scorps are the same. Beauty is only skin deep!
I suppose it may add very slightly to panel stiffness, but what happens if it gets damaged?
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Solo4652
Groupie Joined: 08 Apr 15 Location: Stockport Online Status: Offline Posts: 71 |
Post Options Quote Reply Posted: 01 Nov 15 at 8:28pm |
How about a modern version of heat-shrink skin, maybe impregnated with epoxy?
http://www.gaboats.com/graphics/blivit13_400.jpg |
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Solo4652
Groupie Joined: 08 Apr 15 Location: Stockport Online Status: Offline Posts: 71 |
Post Options Quote Reply Posted: 01 Nov 15 at 9:30pm |
Aircraft-grade alloy tube frame, covered in heat-shrunk skin, epoxied for strength? Not a Streaker, obviously - not allowed by class rules!
https://www.google.co.uk/search?q=alloy+frame+skin+dinghy&source=lnms&tbm=isch&sa=X&ved=0CAgQ_AUoAmoVChMI45KE_JLwyAIVhXsPCh2oiQ3f&biw=1093&bih=538#imgrc=z19s_A5xmWE1sM%3A |
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JimC
Really should get out more Joined: 17 May 04 Location: United Kingdom Online Status: Offline Posts: 6649 |
Post Options Quote Reply Posted: 01 Nov 15 at 9:51pm |
The alloy space frame bit was favoured by some in the 80s. Heavy. Heat shrunk skin would be very slow due to lack of panel stiffness, plus back to the shingly issue.
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Solo4652
Groupie Joined: 08 Apr 15 Location: Stockport Online Status: Offline Posts: 71 |
Post Options Quote Reply Posted: 01 Nov 15 at 10:15pm |
Fibreglass tubing? Carbon tubing?? Surely there must be some sort of lightweight, stiff skin covering? Epoxy-infused cardboard!? Modern glider wings...
I dunno. I'm going to bed. |
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craiggo
Really should get out more Joined: 01 Apr 04 Location: United Kingdom Online Status: Offline Posts: 1810 |
Post Options Quote Reply Posted: 01 Nov 15 at 10:18pm |
There are some very successful ply-foam-ply OKs which are down to weight and seem pretty robust. The ply skins are way thinner than Jim suggests.
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