Composite life expectancy

Speaking of boats, how about those new cats for the America's cup? I never thought a sailing hydrofoil would work without assistance. I saw early versions at SUNY Stonybrook and they could barely stay on the step back then.

Team USA needs to be faster tacking and maybe a better tactician? At least the boat looks fast enough. We shouldn't be 2 races down ( actually, 4 down with penalties)
 
Cap'n Jack said:
Speaking of boats, how about those new cats for the America's cup? I never thought a sailing hydrofoil would work without assistance. I saw early versions at SUNY Stonybrook and they could barely stay on the step back then.

Team USA needs to be faster tacking and maybe a better tactician? At least the boat looks fast enough. We shouldn't be 2 races down ( actually, 4 down with penalties)
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Tactically, the Kiwis came in with the advantage of having to race all the Vuitton Cup challenges, the Oracle team only raced their own after guard tactics. At least 8 races left, and anything can happen including a catastrophic series ending crash.

As for the boats themselves, talk about limited durability! Did you see what happened to the Oracle boat they crashed earlier? These things are so lightly constructed nearly any force outside the exact design force of perfect operations breaks things. These multi million dollar craft will sell for a penny on the dollar next year if that. The mainly difference between the last generation and this is weight, but they still have not solved the stability issues and have managed to kill one guy already.
 
Henning said:
Tactically, the Kiwis came in with the advantage of having to race all the Vuitton Cup challenges, the Oracle team only raced their own after guard tactics. At least 8 races left, and anything can happen including a catastrophic series ending crash.
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I think it's 7 races left since New Zealand won both races today, it's best of 17, so the Kiwis only need 7 more. The USA was down 2 races before today, so they need to win 11 races to win- some sort of penalty for having illegal parts. I think they used NASCAR judges.

Henning said:
As for the boats themselves, talk about limited durability! Did you see what happened to the Oracle boat they crashed earlier? These things are so lightly constructed nearly any force outside the exact design force of perfect operations breaks things. These multi million dollar craft will sell for a penny on the dollar next year if that. The mainly difference between the last generation and this is weight, but they still have not solved the stability issues and have managed to kill one guy already.
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Yep, I did see that. Those boats are made for one thing only- speed for this race, in this stretch of water. Nothing else matters. Did you seen Oracle dropped a guy in the water today before the race?

You were just a kid when the US first lost the America's Cup, but do you remember winged keels seemingly showing up in all new sailboats except maybe Sunfish and some of the Hobie Cats?
 
Cap'n Jack said:
I really didn't inject any feelings. I only asked if it were one of your quizzes, to which you already know the answer. Nothing more or less..
Click to expand...

Isn't this a direct question enough

"Anyone know a good reference for the Epoxy resin life?"

Seems to me, you read a lot into this question that wasn't there.

OBTW, most all AB/EXP aircraft are epoxy/ Glass over foam. Any of the ester resins melt the foam used.
 
Cap'n Jack said:
I think it's 7 races left since New Zealand won both races today, it's best of 17, so the Kiwis only need 7 more. The USA was down 2 races before today, so they need to win 11 races to win- some sort of penalty for having illegal parts. I think they used NASCAR judges.


Yep, I did see that. Those boats are made for one thing only- speed for this race, in this stretch of water. Nothing else matters. Did you seen Oracle dropped a guy in the water today before the race?

You were just a kid when the US first lost the America's Cup, but do you remember winged keels seemingly showing up in all new sailboats except maybe Sunfish and some of the Hobie Cats?
Click to expand...

Lol, yep, I even worked on the Stars and Stripes that lost that race at Driscoll's in San Diego. Terry and I were up on the deck laying out the cut line marks for the reversed transom mod on it when Dennis Conners walked up with another couple of guys pointing to this and that and I wanted to yell down, "Hey Dennis, isn't this the boat you lost the Cup with?":rofl: We also worked on those catamarans and when we put the third mast extension on the 60'er bringing it to 83' while leaving the 20' original beam, we stood back and looked at it and I said, "This thing is gonna fall right over". They towed it out, raised the main (this was before they built the one with the wing) and sure as ****, as soon as it filled, it flipped right over.:rofl:
 
Tom-D said:
Isn't this a direct question enough

"Anyone know a good reference for the Epoxy resin life?"

Seems to me, you read a lot into this question that wasn't there.

OBTW, most all AB/EXP aircraft are epoxy/ Glass over foam. Any of the ester resins melt the foam used.
Click to expand...

Depends which foam you use. The best source for the information you seek is to contact the Gudgeon Brothers or Shell engineers, Shell makes the majority of the epoxy resin in use. As I said earlier, 25 years is a safe bet, after that you have to watch the condition, best way is with a 70° ultrasonic crystal and oscilloscope.
 
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Tom-D said:
Isn't this a direct question enough

"Anyone know a good reference for the Epoxy resin life?"

Seems to me, you read a lot into this question that wasn't there.
Click to expand...
Actually, no. That's why I asked if it were one of your quizzes. If I read stuff that wasn't there, I would simply assume it was one of your quizzes.

I did miss the "epoxy" part, but Henning graciously corrected me and I acknowledged his correction.

Tom-D said:
OBTW, most all AB/EXP aircraft are epoxy/ Glass over foam. Any of the ester resins melt the foam used.
Click to expand...
I'm a little surprised that a mechanic active in the EAB world would make this statement. Like Henning indicated, depends on the foam used. Polyurethane works well with polyester. I believe PVC foam does as well. Agreed most planes use epoxy though.
 
Henning said:
Lol, yep, I even worked on the Stars and Stripes that lost that race at Driscoll's in San Diego. Terry and I were up on the deck laying out the cut line marks for the reversed transom mod on it when Dennis Conners walked up with another couple of guys pointing to this and that and I wanted to yell down, "Hey Dennis, isn't this the boat you lost the Cup with?":rofl: We also worked on those catamarans and when we put the third mast extension on the 60'er bringing it to 83' while leaving the 20' original beam, we stood back and looked at it and I said, "This thing is gonna fall right over". They towed it out, raised the main (this was before they built the one with the wing) and sure as ****, as soon as it filled, it flipped right over.:rofl:
Click to expand...

I don't understand your statement. It was Liberty that lost that race in New York (actually, Newport, RI). Stars & Stripes got the cup back, Conner captained both of them. We won the cup back somewhere near Fremantle, Australia.
 
Cap'n Jack said:
Actually, no. That's why I asked if it were one of your quizzes. If I read stuff that wasn't there, I would simply assume it was one of your quizzes.

I did miss the "epoxy" part, but Henning graciously corrected me and I acknowledged his correction.


I'm a little surprised that a mechanic active in the EAB world would make this statement. Like Henning indicated, depends on the foam used. Polyurethane works well with polyester. I believe PVC foam does as well. Agreed most planes use epoxy though.
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I'm not sure that's even correct, many of the plane I have seen have been vinylester, and if I built one from glass, it would likely be my choice as well. From what I have seen, polyester is the most widely used with glass due to cost, and most of the planes that use epoxy are carbon fiber which is a rather limited amount of the offerings.

The three resins typically used are polyester, vinylester, and epoxy; that is from cheapest to most expensive with each step doubling the price of the former.

Can anyone explain to me the advantage of using epoxy over vinylester when using E or S glass?:dunno: I can't think of one with the exception of pot life for those inexperienced at doing layups.
 
Cap'n Jack said:
I don't understand your statement. It was Liberty that lost that race in New York (actually, Newport, RI). Stars & Stripes got the cup back, Conner captained both of them. We won the cup back somewhere near Fremantle, Australia.
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Sorry, should have clarified, Liberty had been renamed Stars and Stripes as well when she went into charter service at the Kona Kai doing day sails.
 
Tom-D said:
Here is the recommended materials

http://aircraftproducts.wicksaircra...05?&plpver=10&origin=keyword&by=prod&filter=0
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For which? BTW, I'll use that stuff for making plug, seal it with a latex paint, use poly or vinylester layup over it, then put a little gas in there to get rid of the plug when I'm making hollow stuff. Selling them polystyrene is a great way to get them to buy more expensive epoxy from them, however I'm still looking for the advantage of using epoxy over vinylester.:dunno:
 
Tom-D said:
The coZY & LongEZ kit that AS&S sells is what most EZ builders use, and the ester resins melt it.
Click to expand...


The vinyl and polyesther resins use styrene as a polymer and thinner so you are correct that it melts the styrofoam used in the rutan planes. That means you're stuck with epoxy of some type for this application. Most of the rutan stuff used safety poxy in the timeframe you were asking about We did some testing back in the 80's and 90's with that resin in a variety of situations. In the New Mexico sun it did pretty poorly for UV degradation and the bond with the styrofoam also had some delamination issues with outdoor environmental changes. We had parts in covered storage that were exposed to the extremes of temp found in the albuquerque area and the foam delaminated even with sunshade. Most of what we did with that resin system was building of propellers and parts for the Falcon Ultralight. I saw one of the propellers a year or so back that had been on a Falcon in a hanger for about 25 years. It looked pretty good. On the other hand the reject I had hanging in my garage for display died years ago due to UV exposure. I don't have a lot of faith in the styrofoam core setups used in the rutan designs and if I found a brand new one I still wouldn't fly it. Thats personal opinion based on the years I built gliders ( Zuni II 15m), prototypes of various sorts and RPV's for various govt agencies. We also used a lot of shell products like 815 and 828 with various curing compounds. We also used a variety of Ciba Geigy and Hysol resins and glues. The common thread with all of these is exposure to elements that degrade the resin or the reinforcement. This is all assuming that the original structure is properly done and to this day the methods of testing are still controversial when compared to metal or wood. Voids and delams are not always detectable. Improperly mixed or improperly ratio'd resins are hard to detect and proper wetting of the reinforcement is not always reasonably detectable. That is one reason composite aircraft are overbuilt. Many of the early gliders from the 60's and 70's are still flying safely and mostly that is due to storage and maintainance of the paint. George Applebay in Moriarty New Mexico has been building, repairing and maintaining composite sailplanes and other aircraft since the 50's and could probably give you a better answer than any of us. He has hands on experience working with real world composites that many of us don't.
So having said all that the answer to your question is no closer. As the others said you need more info to get a better answer.


Frank
 
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Henning said:
For which? BTW, I'll use that stuff for making plug, seal it with a latex paint, use poly or vinylester layup over it, then put a little gas in there to get rid of the plug when I'm making hollow stuff. Selling them polystyrene is a great way to get them to buy more expensive epoxy from them, however I'm still looking for the advantage of using epoxy over vinylester.:dunno:
Click to expand...

The strength of a glass over foam structure comes from direct attachment of the glass to the foam using your method would have the skin coming loose due to the laytex layer between the two. I'll stick to proven methods and materials.
 
Tom-D said:
The strength of a glass over foam structure comes from direct attachment of the glass to the foam using your method would have the skin coming loose due to the laytex layer between the two. I'll stick to proven methods and materials.
Click to expand...

Lol, polystyrene is the worst possible lowest grade foam for any structural use, nobody building a foam core structure commercially uses it. I wouldn't build a plane using it no way no how, far too many problems with delamination not only of the laminate bond, but within the foam itself. Even if you get a good seal to the surface, you only get the top layer of beads and in time they break away from the beads below. I'd use Airex foam if it had to be structural in nature.

You have brought up an issue that is beyond that of "how long is the epoxy good for?" The epoxy can still be fine but the foam below it junk. If the polystyrene foam is integral to the structural strength, I'd say the structure will be questionable at 10years/1500hrs, whichever comes first.
 
Henning said:
Lol, polystyrene is the worst possible lowest grade foam for any structural use, nobody building a foam core structure commercially uses it. I wouldn't build a plane using it no way no how, far too many problems with delamination not only of the laminate bond, but within the foam itself. Even if you get a good seal to the surface, you only get the top layer of beads and in time they break away from the beads below. I'd use Airex foam if it had to be structural in nature.

You have brought up an issue that is beyond that of "how long is the epoxy good for?" The epoxy can still be fine but the foam below it junk. If the polystyrene foam is integral to the structural strength, I'd say the structure will be questionable at 10years/1500hrs, whichever comes first.
Click to expand...

I will guess your opinion is disproven by the number of VaryEZ, CoEZ and the LongEZ that are out there flying for the past 30 years.

I have a ATA in marine tech, and have worked for companies that build boats like Raider marine, Dakota Creet In Anacortes Wa and the old canoe builder in LaConner Wa.
I have used all three resins and most of the foams in their shops. building all kinds of parts. And what you are saying here hasn't worked there.
 
Tom-D said:
I will guess your opinion is disproven by the number of VaryEZ, CoEZ and the LongEZ that are out there flying for the past 30 years.

I have a ATA in marine tech, and have worked for companies that build boats like Raider marine, Dakota Creet In Anacortes Wa and the old canoe builder in LaConner Wa.
I have used all three resins and most of the foams in their shops. building all kinds of parts. And what you are saying here hasn't worked there.
Click to expand...

All it proves is that the laminate is overbuilt and the foam core not necessary. What have I said here that doesn't work there?
 
BiffJ said:
The vinyl and polyesther resins use styrene as a polymer and thinner so you are correct that it melts the styrofoam used in the rutan planes. That means you're stuck with epoxy of some type for this application. Most of the rutan stuff used safety poxy in the timeframe you were asking about We did some testing back in the 80's and 90's with that resin in a variety of situations. In the New Mexico sun it did pretty poorly for UV degradation and the bond with the styrofoam also had some delamination issues with outdoor environmental changes. We had parts in covered storage that were exposed to the extremes of temp found in the albuquerque area and the foam delaminated even with sunshade. Most of what we did with that resin system was building of propellers and parts for the Falcon Ultralight. I saw one of the propellers a year or so back that had been on a Falcon in a hanger for about 25 years. It looked pretty good. On the other hand the reject I had hanging in my garage for display died years ago due to UV exposure. I don't have a lot of faith in the styrofoam core setups used in the rutan designs and if I found a brand new one I still wouldn't fly it. Thats personal opinion based on the years I built gliders ( Zuni II 15m), prototypes of various sorts and RPV's for various govt agencies. We also used a lot of shell products like 815 and 828 with various curing compounds. We also used a variety of Ciba Geigy and Hysol resins and glues. The common thread with all of these is exposure to elements that degrade the resin or the reinforcement. This is all assuming that the original structure is properly done and to this day the methods of testing are still controversial when compared to metal or wood. Voids and delams are not always detectable. Improperly mixed or improperly ratio'd resins are hard to detect and proper wetting of the reinforcement is not always reasonably detectable. That is one reason composite aircraft are overbuilt. Many of the early gliders from the 60's and 70's are still flying safely and mostly that is due to storage and maintainance of the paint. George Applebay in Moriarty New Mexico has been building, repairing and maintaining composite sailplanes and other aircraft since the 50's and could probably give you a better answer than any of us. He has hands on experience working with real world composites that many of us don't.
So having said all that the answer to your question is no closer. As the others said you need more info to get a better answer.


Frank
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That's probably the most definitive answer we have in this whole thread.

And what I get from it is simply this, it matters not what foam you use, it is the laminate that is the aircraft.

the plans built EZs are all built using the blue foam from either store is simply the easiest to use.
check it out here
http://www.youtube.com/watch?v=RkkD9lZ8C-4
 
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Tom-D said:
And what I get from it is simply this, it matters not what foam you use, it is the laminate that is the aircraft.
Click to expand...

Do you mean EZ aircraft or all composite aircraft with that statement?
 
Tom-D said:
Not all composite aircraft are 1 off construction.
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How does this answer the question? I still don't know whether you placed all foam core structures under the statement or just some of them ( Cozy /EZ ).
 
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Tom-D said:
That's probably the most definitive answer we have in this whole thread.

And what I get from it is simply this, it matters not what foam you use, it is the laminate that is the aircraft.

the plans built EZs are all built using the blue foam from either store is simply the easiest to use.
check it out here
http://www.youtube.com/watch?v=RkkD9lZ8C-4
Click to expand...

Depends, are there stringers built into the foam cored structure or not? If not, then the foam core IS part of the structure and important.
 
Cap'n Jack said:
I'm still confused...I thought the Stars & Stripes in San Diego was built years after the race?

http://www.sandiegotours.us/?event=offer.detail&offerId=3426

There's a rumor that the original Liberty (US 40) was lost off Japan.
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??? Never heard that, last I heard she was still hauling rides in Mexico. To the best of my knowledge the one we cut the transom back on was the one that lost the cup race, I may have been given a bad rumor. They used to "match race" the two boats on day charters out of the Kona Kai club on Shelter Island in the late 80s, then I heard they went down to Puerto Vallarta,not sure where they are now. If you keep up with the old 12meters, I'd like to know where Valient, the last of the wood 12meters is, I used to sail her when Shirley Kern had her.
 
Henning said:
Lol, polystyrene is the worst possible lowest grade foam for any structural use, nobody building a foam core structure commercially uses it. I wouldn't build a plane using it no way no how, far too many problems with delamination not only of the laminate bond, but within the foam itself. Even if you get a good seal to the surface, you only get the top layer of beads and in time they break away from the beads below. I'd use Airex foam if it had to be structural in nature.

You have brought up an issue that is beyond that of "how long is the epoxy good for?" The epoxy can still be fine but the foam below it junk. If the polystyrene foam is integral to the structural strength, I'd say the structure will be questionable at 10years/1500hrs, whichever comes first.
Click to expand...

The foam is not structural, merely a form. So if the styrene will hold up long enough for the resin to set...

I would shudder to think that my a$$ was on th' line with a styrofoam spar. Back in the early days of the Vari-ezy Burt told me that the foam is used only as a form for the composite structure.
 
bluerooster said:
The foam is not structural, merely a form. So if the styrene will hold up long enough for the resin to set...

I would shudder to think that my a$$ was on th' line with a styrofoam spar. Back in the early days of the Vari-ezy Burt told me that the foam is used only as a form for the composite structure.
Click to expand...

I thought Tom said it was structural, I don't know anything about those designs. I always assumed the foam was just a plug to do the layup on. Personally if I built one I would build a mold.
 
Henning said:
I thought Tom said it was structural, I don't know anything about those designs. I always assumed the foam was just a plug to do the layup on. Personally if I built one I would build a mold.
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I missed the part about being structural. But I find it hard to believe that foam could be anything more than a form.

Using foam, is faster/easier than building a mold.
 
bluerooster said:
The foam is not structural, merely a form. So if the styrene will hold up long enough for the resin to set...

I would shudder to think that my a$$ was on th' line with a styrofoam spar. Back in the early days of the Vari-ezy Burt told me that the foam is used only as a form for the composite structure.
Click to expand...


This is not true, the foam is a structural part and needs to be bonded to the skin to retain full strength. It is a shear web that keeps the skins on opposite sides from moving in relation to each other. It is like the center of an "I" beam....its not so much directly part of the strength, it keeps the spar caps at a constant distance and prevents them from moving. The top cap is in tension, the lower in compression. If you break the bond to the web (foam) than the caps can move and buckle losing strength. The Vari EZ and its contemporary types of one off are overbuilt to account for this or they would not still be flying today. The ones that sit outside in the sun don't do well because only do the foam and skin delam, the resin binder decays. The resin is similar to the foam in that it carries the load from fiber to fiber and when it decays the fibers won't carry the load.

Are there a lot of EZ's and planes of that type with a lot of flying time? If you did a load test on one today that was built 20 year ago would it pass? A lot of older planes are still flying today that are marginal so using the thought that they are flying as an example of structural integrity isn't the right way to go. Look at Grade A cotton on old aircraft. When its dead it starts peeling....if you get a place to start. Sometimes you can get away with flying a plane that has fabric which is really dead but it doesn't mean its good to go. I built a lot of prototypes using the one-off glass or carbon over foam core but none were intended to last very long. The production stuff was always molded and anything using a core used a foam that was intended to last like PVC, Acrylic etc. This stuff doesn't die after a year like styro and turn to powder. The bond with the skins will live a long time because the foam is strong enough.

Hope that adds to the discussion.

Frank
 
BiffJ said:
This is not true, the foam is a structural part and needs to be bonded to the skin to retain full strength. It is a shear web that keeps the skins on opposite sides from moving in relation to each other. It is like the center of an "I" beam....its not so much directly part of the strength, it keeps the spar caps at a constant distance and prevents them from moving. The top cap is in tension, the lower in compression. If you break the bond to the web (foam) than the caps can move and buckle losing strength. The Vari EZ and its contemporary types of one off are overbuilt to account for this or they would not still be flying today. The ones that sit outside in the sun don't do well because only do the foam and skin delam, the resin binder decays. The resin is similar to the foam in that it carries the load from fiber to fiber and when it decays the fibers won't carry the load.

Are there a lot of EZ's and planes of that type with a lot of flying time? If you did a load test on one today that was built 20 year ago would it pass? A lot of older planes are still flying today that are marginal so using the thought that they are flying as an example of structural integrity isn't the right way to go. Look at Grade A cotton on old aircraft. When its dead it starts peeling....if you get a place to start. Sometimes you can get away with flying a plane that has fabric which is really dead but it doesn't mean its good to go. I built a lot of prototypes using the one-off glass or carbon over foam core but none were intended to last very long. The production stuff was always molded and anything using a core used a foam that was intended to last like PVC, Acrylic etc. This stuff doesn't die after a year like styro and turn to powder. The bond with the skins will live a long time because the foam is strong enough.

Hope that adds to the discussion.

Frank
Click to expand...

Interesting.
After talking to several EZ builders/flyers. They assured me that the shear web was fabricated of fiberglass, not foam, and the foam was simply a form.
The wing is shaped out of foam, Glass is then layed up, and allowed to set, then the wing is split longitudinally, into 3 parts. The narrowest of those parts becomes the spar which is layed with glass all by it's self, with the weave running at 45* to the length, thus building a box spar, with tension, and compression members of composite material, and also the shear web, being of the same material. Then the 3 parts are put back together, and "glassed in".
Back in the early 70's they didn't trust the foam to act as a structural member.
Mabe they do now.
 
Cap'n Jack said:
How does this answer the question? I still don't know whether you placed all foam core structures under the statement or just some of them ( Cozy /EZ ).
Click to expand...

It would answer the question if you knew the difference between 1 off, and a molded structure.

1 Off, you shape the foam, and cover with a layup. the resin can't attack the foam or the shape changes, the blue foam that AS&S sells is Styrofoam and weighs much less than any thing Henning is talking about. that is a big thing in aircraft construction.

molded structures are made from deep cavity mold, or autoclave and usually vacuum bagged, to reduce the weight by removing excess resin and air.
The routine is normally coat the mold with gel-coat of the color you like, allow to jell, lay up random fiber, and roving behind that, suck out the access resin and air, allow to set and then remove the part. After that you can sandwich in any foam you like for strength thickness and insolation. this is the process that the resent glass kit builders use in making the glassair, velocity, and others

Processes have come a longways since I last worked the industry, in the late 80's
 
RotorAndWing said:
Just be sure to check a few "facts" before believing anything.......:rolleyes:
Click to expand...

At least talk to one posting in the open, and not hiding behind a monicker with nothing anywhere proving what or who they are.

Me I'm pretty much an open book, here and other pages, as is Ron, Jay, and many other who have integrity.
 
Henning said:
??? Never heard that, last I heard she was still hauling rides in Mexico. To the best of my knowledge the one we cut the transom back on was the one that lost the cup race, I may have been given a bad rumor. They used to "match race" the two boats on day charters out of the Kona Kai club on Shelter Island in the late 80s, then I heard they went down to Puerto Vallarta,not sure where they are now. If you keep up with the old 12meters, I'd like to know where Valient, the last of the wood 12meters is, I used to sail her when Shirley Kern had her.
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I'm pretty sure the name is spelled "Valiant", she's still sailing around Marblehead, MA.

This link has a picture from a couple of years ago:
http://sparkmanstephens.blogspot.com/2011/11/more-about-valiant-design-1978.html

They still "race" the 12 meters in San Diego if they get enough people for their trips. I think it's a "3 hour tour"? :hairraise:

I've seen them advertising those tours seems like forever, there's trade shows there periodically I attend (Neuroscience, ACS, Pharmacognosy, etc), they've been there for some time.
 
Tom-D said:
At least talk to one posting in the open, and not hiding behind a monicker with nothing anywhere proving what or who they are.

Me I'm pretty much an open book, here and other pages, as is Ron, Jay, and many other who have integrity.
Click to expand...

I personally tend to judge the posts made, less so the name.

Does it really matter what the name is under if the information is incorrect or lies?
 
Tom-D said:
It would answer the question if you knew the difference between 1 off, and a molded structure.

1 Off, you shape the foam, and cover with a layup. the resin can't attack the foam or the shape changes, the blue foam that AS&S sells is Styrofoam and weighs much less than any thing Henning is talking about. that is a big thing in aircraft construction.

molded structures are made from deep cavity mold, or autoclave and usually vacuum bagged, to reduce the weight by removing excess resin and air.
The routine is normally coat the mold with gel-coat of the color you like, allow to jell, lay up random fiber, and roving behind that, suck out the access resin and air, allow to set and then remove the part. After that you can sandwich in any foam you like for strength thickness and insolation. this is the process that the resent glass kit builders use in making the glassair, velocity, and others

Processes have come a longways since I last worked the industry, in the late 80's
Click to expand...
Thanks for the explanation. the confusion comes from idioms- "one-off" can also mean a single item made only once by some one, as most homebuilt aircraft are.

Some of the kits are made in a mold, as you mentioned and they could be described as a "one off" since the builder is making a single plane; this doesn't prevent them from making multiple copies, but many plans specify, as part of their license agreement, that the builder may make only a single aircraft with that copy of the plans. If they want to make another plane of the same type, they should purchase another set of plans.

http://www.thefreedictionary.com/one-off
 
Cap'n Jack said:
I'm pretty sure the name is spelled "Valiant", she's still sailing around Marblehead, MA.

This link has a picture from a couple of years ago:
http://sparkmanstephens.blogspot.com/2011/11/more-about-valiant-design-1978.html

They still "race" the 12 meters in San Diego if they get enough people for their trips. I think it's a "3 hour tour"? :hairraise:

I've seen them advertising those tours seems like forever, there's trade shows there periodically I attend (Neuroscience, ACS, Pharmacognosy, etc), they've been there for some time.
Click to expand...

It couldn't be less than a three hour tour, those boats are sloooow.:rofl:
 
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