>>>>I took a quick tumb through a couple of ww/touring catalogs and didn't see a foot operated bilge pump either. Anyone know where one can be had? <<< any dealer of valley/nigel dennis kayaks will be able to supply the british "chimp" foot pump, list price is $175 (ouch!), but worth it. i tried several years ago (prior to becoming a dealer myself) to adapt a whale pump (much less pricey) by installing an internal spring to allow use as a foot pump, it worked but not as well as the chimp, and was much bulkier which added to the installation woes. In addition i always was a little wrried about relying on it in survival conditions. the other great thing abot foot pumps is the ability to easlily pump out the water that invariably accumulates when surfing/playing in waves. george ruta northcountry kayak 518-677-3040 *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
I recently purchased a new Carbon/Kevlar Nordkapp which was probably made in 95 or 96. It did have a few minor star shaped cracks in it from prior demos, but was in new condition. I have only launched the boat from knee deep water till this weekend, when I took it to the beach where I "Seal Launched" of the sand into 1 foot seas. The action of flexing the hull from sitting on the sand, then lifting the boat has created huge cracks in the clear gelcote. The cracks are 3 or 4 feet long and substantial enough to have flakes of gelcote fall out. In addition there are other worsening cracks in the the deck above the rear bulkhead. This sounds like a defective gelcote? When I press on the hull, I hear the sound of one hull cracking! Before I ream Valley a new orafice, I wonder if anyone has any comments or suggestions. I have not experienced anything similar with either my Seda Impulse or Falcon 16. I had heard that Valley had received some misinformation about working with Carbon/Kevlar and it seems that the Gelcote doesn't have the flexibility required by the hull and deck and it seems to shatter as if it were made of glass. I really love the boat and am just starting to get comfortable with it. Thanks for the input. I am going to request a new boat if they don't have a magical solution. Cya Bob Denton Gulf Stream International Boynton Beach, Florida Internet Web Site Development *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
Bob wrote; I have only launched the boat from knee deep water till this weekend, when I took it to the beach where I "Seal Launched" of the sand into 1 foot seas. The action of flexing the hull from sitting on the sand, then lifting the boat has created huge cracks in the clear gelcote. The cracks are 3 or 4 feet long and substantial enough to have flakes of gelcote fall out. In addition there are other worsening cracks in the the deck above the rear bulkhead. This sounds like a defective gelcote? When I press on the hull, I hear the sound of one hull cracking! (SNIPS) I am not fond of carbon fiber where there will be impact or large localised loads. When it breaks it really breaks unlike Kevlar that has greater tolerance to impact. The problem with many of these hi-tech materials is that they require careful engineering. I remember when Kevlar first came along and people tried to build boats using regular polyester resins. What a disaster! It is important to match all the materials. These days builders are more savvy and use flexible vinylesters and flexible gel coats. Even so, things go wrong. The problem with Bob's boat sounds (but may not be) like a rigid polyester gel coat or maybe even an incompatible gel coat (incompatible with the laminating resin). One really has to see the thing to form a reliable assessment though. I would like to know what resin was used to build the boat and what gel coat. Of course, for the lay person this isn't much help. But at least one should know if the resin was epoxy, vinyl ester or iso or orthopthalic polyester. If it is one of the latter two then I would be upset. Properly built carbon boats are remarkably strong especially when matched to the proper core material and with the fibers properly oriented. Usually they are made from epoxy pre-pregs vacuum and heat cured under pressure. I had a canoe that was built that way and it was truly remarkable. One of the great sins is to use the mixed materials (carbon/Kevlar) cloth. It looks sexy but the result is poor. As Hank Hays says, "Carbon is not all it's cracked up to be" Cheers, John Winters Redwing Designs Specialists in Human Powered Watercraft http://home.ican.net/~735769/ *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
John Winters wrote: > ...SNIP.. > One of the > great sins is to use the mixed materials (carbon/Kevlar) cloth. It looks > sexy but the result is poor. ... John, I am hoping that you can elaborate on the above. I was talking to a well-respected Seattle boat designer who suggested that carbon/kevlar weaves are an excellent material for kayaks from the standpoint of durability. (Fortunately I haven't yet acted on his advice.) He claimed that the carbon/kevlar weave avoids the excessive brittleness of carbon and the excessive flex of kevlar. To back up his claims, he has some "squares" of various composites (complete with gel coat) which he bangs on with a hammer to simulate the effects of impacts. (Some of you may know to whom I am referring.) The carbon/kevlar weave did in fact seem to tolerate this treatment quite well. I had been planning to order another kevlar boat, as I have found my current kevlar boat to be quite resilient, in spite of rather rough treatment. (I have gouged out the gel coat where I have had heavy impacts with barnacle-encrusted reefs, but I have had no gel coat cracks or any other damage.) However I was told that the carbon/kevlar weave would be even more durable than kevlar. It is difficult to get information on this new material. Any experiences that you might be willing to share would be most appreciated, as the stuff ain't cheap. We certainly don't want any more paddlewisers to hear the sound of one hull cracking! Dan Hagen Bellingham, Washington *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
The fabric used in this boat is a Carbon - Kevlar weave. The boat was built in 1995 (but purchased new a few weeks ago) and I was informed that Valley has changed the way they cure the boat..it's now "baked". The gelcote is almost glass like in brittleness and sort of shatters... a small impact produces a star like crack. Great River stated that they will probably replace the boat once they have a chance to verify the details with Valley. John, thanks for your detailed response. I'll pass on any specific information about the layup that I receive. > This sounds like a defective gelcote? When I press on the hull, I > hear the sound of one hull cracking! > > (SNIPS) > > I am not fond of carbon fiber where there will be impact or large localised > loads. When it breaks it really breaks unlike Kevlar that has greater > tolerance to impact. The problem with many of these hi-tech materials is > that they require careful engineering. I remember when Kevlar first came > along and people tried to build boats using regular polyester resins. What > a disaster! It is important to match all the materials. These days builders > are more savvy and use flexible vinylesters and flexible gel coats. Even > so, things go wrong. > > The problem with Bob's boat sounds (but may not be) like a rigid polyester > gel coat or maybe even an incompatible gel coat (incompatible with the > laminating resin). One really has to see the thing to form a reliable > assessment though. I would like to know what resin was used to build the > boat and what gel coat. Of course, for the lay person this isn't much help. > But at least one should know if the resin was epoxy, vinyl ester or iso or > orthopthalic polyester. If it is one of the latter two then I would be > upset. > > Properly built carbon boats are remarkably strong especially when matched > to the proper core material and with the fibers properly oriented. Usually > they are made from epoxy pre-pregs vacuum and heat cured under pressure. I > had a canoe that was built that way and it was truly remarkable. One of the > great sins is to use the mixed materials (carbon/Kevlar) cloth. It looks > sexy but the result is poor. > > As Hank Hays says, "Carbon is not all it's cracked up to be" > > Cheers, > John Winters > Redwing Designs > Specialists in Human Powered Watercraft > http://home.ican.net/~735769/ > > > > *************************************************************************** > PaddleWise Paddling Mailing List > Submissions: paddlewise_at_lists.intelenet.net > Subscriptions: paddlewise-request_at_lists.intelenet.net > Website: http://www.gasp-seakayak.net/paddlewise/ > *************************************************************************** > > Bob Denton Gulf Stream International Boynton Beach, Florida Internet Web Site Development *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
Dan wrote; > >I am hoping that you can elaborate on the above. I was talking to a >well-respected Seattle boat designer who suggested that carbon/kevlar >weaves are an excellent material for kayaks from the standpoint of >durability. (SNIP) The problem with these mixed weave fabrics is that they produce stress concentrations within the layer. I have examined four boats that had your typical impact with a rock and there were cracks travelling along the carbon fiber fill extending to a point where the stiffness increased rapidly. I think that the hammer test is not very representative of real life . In real life the impact causes large area flexure that terminates at a bulkhead or the sheer, or the turn of the bilge. Builders of my designs also use these materials and I have had little success in talking them out of it because it looks so sexy. In discussions with J.B. Martin, a company that makes various types of combination materials they have always said that the mixed weaves were poor for boats. They recommend stitched materials (non-woven with the Kevlar on one side and the carbon on the other. This was the type of laminate we used many years ago (we did not have carbon then but used S glass) when I was building racing sailboats and we had great success with it. I can recall Darryl Lideigh (SP?) hammering on his chopped strand canoes and challenging builders of Kevlar boats to do likewise. Of course, it was not an appropriate test. One has to compare similar weights etc. O course, hammering on a laminate is not very scientific or consistent. That is why companies use independent labs with appropriate test facilities to verify laminate characteristics. Your friendly boat builder may build fine boats (I suspect he does) but I would be wary of specious comparisons. Without knowing what types of laminates he was comparing it is awfully hard to say much about the comparison. If were seeking the lightest possible boat there is no question that is would have to be carbon fiber pre pregs over honeycomb and heat cured. If I were seeking the lightest boat that would withstand repeated impacts etc. it would be a Kevlar skinned boat with a syntactic foam core using a high impact resistant microballon and a moderately flexible resin carrier, If I were seeking the toughest damned kayak the world it would be a Kevlar skinned boat with carbon fiber cores, epoxy heat cured resin system and all laminates unidirectional and oriented appropriately. What I have is a cheap Fiberglas kayak, a couple of beat-up strippers canoes, One gorgeous Martin Step stripper canoe that I use once a year, two Kevlar syntactic foam canoes that I use all the time boats and one Royalex kayak that I think I am going to like. Obviously I don't always practice what I preach. :-) Cheers, John Winters Redwing Designs Specialists in Human Powered Watercraft http://home.ican.net/~735769/ *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
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