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<blockquote data-quote="charlietrotter" data-source="post: 4627861" data-attributes="member: 31212"><p>No, non e' vero: anche io avevo segnalato in precedenza le mie preoccupazioni quando vidi su velobuild.com alcune lesioni al canotto reggisella di alcuni fm066 (che possiedo, fortunatamente integro)....telai crepati tra l'altro alla prima uscita: sospetto segno di un chiaro problema in fase di nascita, da qui la mia preoccupazione. </p><p> </p><p> </p><p>Comunque a parte questo ho trovato questo interessante monologo su un altro forum (il problema, e' che non so' chi sia lo scrivente, per cui vale tanto quanto niente...):</p><p> </p><p>Sorry, my post is a bit long, bear with me, but this post and some of the things stated are just plain wrong and misguided.</p><p>Are you trying to say that an "open" mold is defined as one that a big manufacture is no longer using due to it going out of "spec", and just let some company buy it and then make their own frames from that old mold?</p><p></p><p>There are a handful of well known manufacturers in China/Taiwan that have factories that produce, on a contract, the big name brand carbon framesets. Those designs, IP and the actual "molds" themselves are proprietary and only they can use those to make their bikes. If the molds do become damage, out of spec or whatever, they are scrapped. They can't just sell it to somebody else and let them use it to make their own frames at a smaller factory. That would put them in jeopardy of losing their contract and business.</p><p></p><p>The open mold factories are just that. They are companies that have invested hundreds of thousands of dollars to produce their own frames/molds that are generic in nature. They then intend to sell the frames they make to any middle man, or company, many in the US or around the World, as any name brand they want. There is no intellectual property involved, one company can use the exact same mold/frame and label it as their own, as well as any other company that sells the frame. Each bike mold costs about $8k to make. They have to machine the mold from solid aluminum, like any other industry using mold techniques, and to exact specifications and tolerances. These are often generic designs, or as we have seen, designs that are near direct ripoffs of the exact size/design/style/geometry of big name frames. Like the Scott Foil or Venge.</p><p></p><p>Open mold or not, none of these people make their own carbon fiber fabric. Toray of Japan is probably the largest in the World who provide/sell the actual carbon fiber fabric to many/most bike manufacturers. T700, T1000 etc...are names people have heard and that are being used widely today. They buy the sheets, cut them to the templates they have designed, then start laying them up by hand with one of the various carbon layup techniques/methods commonly used, or specified by the company they are doing the work for. There is very little difference between carbon layup techniques that apply to most industry. Car parts, bikes or whatever. Not much has changed in that respect.</p><p></p><p>The real differences are just how it is laid up to achieve a certain ride quality and stiffness at different places and junctures, or how the frame is assembled, maybe it is a one piece monocoque mold, or multiple pieces from several molds that get glued together at various staged to complete the frame. But they all use very similar techniques to wrap the fabric around the mold, resin and pressure to shape and cure/harden the product. Then it is all hand finish work mostly from that point onward out of the mold.</p><p></p><p>Most of these open mold manufacturers have a huge investment in their business. Nearly all perform standardized testing, like the big name contractors, to ensure the quality and final product of the frame meets industry accepted specifications. If they make junk, their business will fail eventually, that is plain and simple. The internet forums, being what they are, would always have new threads claiming my (insert small non-big name bike frame/open mold) bike frame imploded! You hear examples of this once in awhile from major brands also. This is the nature of carbon fiber and the manufacturing process with nearly everything made today.</p><p></p><p>Now, I will tell you there are definitely minor QC/finish issues of Chinese open mold frames compared to the bigger brands. They do put more time/effort into that aspect. Particularly paint, some internal sanding/finishing of the surfaces to smooth them out and such. But does that make a Trek Madone stronger and better than a regular Chinese open mold like the FM098? Not likely. They are using very similar, if not identical carbon fiber sheets, resins, similarly made molds and the techniques are very close, thus, the end result is very similar from an overall integrity and structural aspect of the product. The difference of ride quality of a Venge, and the FM098, will be similar since they use the exact geometry on nearly every size. But how the bike handles/ride/takes bumps etc..might be slightly different. It is hard to say without having both bikes built identically, except with different frames, to determine that.</p><p></p><p>Giving an example of a Cervelo R5ca is an extreme example. There are very few companies that have a product like that. They hand lay up those frames in CA by a few select people with expertise and some unique techniques, and produce them in a very extreme limited quantity. Like 100 I believe. Same with the McClaren Venge. </p><p></p><p>If people don't want an open mold frame, then don't buy it. That simple. But claiming there are such huge differences between your typical big name frame and an open mold one is a bit misguided and uninformed. Doesn't mean there aren't open molds that are junk and not good, but typically, they have proven over time to be just as reliable as any big name brand.</p></blockquote><p></p>
[QUOTE="charlietrotter, post: 4627861, member: 31212"] No, non e' vero: anche io avevo segnalato in precedenza le mie preoccupazioni quando vidi su velobuild.com alcune lesioni al canotto reggisella di alcuni fm066 (che possiedo, fortunatamente integro)....telai crepati tra l'altro alla prima uscita: sospetto segno di un chiaro problema in fase di nascita, da qui la mia preoccupazione. Comunque a parte questo ho trovato questo interessante monologo su un altro forum (il problema, e' che non so' chi sia lo scrivente, per cui vale tanto quanto niente...): Sorry, my post is a bit long, bear with me, but this post and some of the things stated are just plain wrong and misguided. Are you trying to say that an "open" mold is defined as one that a big manufacture is no longer using due to it going out of "spec", and just let some company buy it and then make their own frames from that old mold? There are a handful of well known manufacturers in China/Taiwan that have factories that produce, on a contract, the big name brand carbon framesets. Those designs, IP and the actual "molds" themselves are proprietary and only they can use those to make their bikes. If the molds do become damage, out of spec or whatever, they are scrapped. They can't just sell it to somebody else and let them use it to make their own frames at a smaller factory. That would put them in jeopardy of losing their contract and business. The open mold factories are just that. They are companies that have invested hundreds of thousands of dollars to produce their own frames/molds that are generic in nature. They then intend to sell the frames they make to any middle man, or company, many in the US or around the World, as any name brand they want. There is no intellectual property involved, one company can use the exact same mold/frame and label it as their own, as well as any other company that sells the frame. Each bike mold costs about $8k to make. They have to machine the mold from solid aluminum, like any other industry using mold techniques, and to exact specifications and tolerances. These are often generic designs, or as we have seen, designs that are near direct ripoffs of the exact size/design/style/geometry of big name frames. Like the Scott Foil or Venge. Open mold or not, none of these people make their own carbon fiber fabric. Toray of Japan is probably the largest in the World who provide/sell the actual carbon fiber fabric to many/most bike manufacturers. T700, T1000 etc...are names people have heard and that are being used widely today. They buy the sheets, cut them to the templates they have designed, then start laying them up by hand with one of the various carbon layup techniques/methods commonly used, or specified by the company they are doing the work for. There is very little difference between carbon layup techniques that apply to most industry. Car parts, bikes or whatever. Not much has changed in that respect. The real differences are just how it is laid up to achieve a certain ride quality and stiffness at different places and junctures, or how the frame is assembled, maybe it is a one piece monocoque mold, or multiple pieces from several molds that get glued together at various staged to complete the frame. But they all use very similar techniques to wrap the fabric around the mold, resin and pressure to shape and cure/harden the product. Then it is all hand finish work mostly from that point onward out of the mold. Most of these open mold manufacturers have a huge investment in their business. Nearly all perform standardized testing, like the big name contractors, to ensure the quality and final product of the frame meets industry accepted specifications. If they make junk, their business will fail eventually, that is plain and simple. The internet forums, being what they are, would always have new threads claiming my (insert small non-big name bike frame/open mold) bike frame imploded! You hear examples of this once in awhile from major brands also. This is the nature of carbon fiber and the manufacturing process with nearly everything made today. Now, I will tell you there are definitely minor QC/finish issues of Chinese open mold frames compared to the bigger brands. They do put more time/effort into that aspect. Particularly paint, some internal sanding/finishing of the surfaces to smooth them out and such. But does that make a Trek Madone stronger and better than a regular Chinese open mold like the FM098? Not likely. They are using very similar, if not identical carbon fiber sheets, resins, similarly made molds and the techniques are very close, thus, the end result is very similar from an overall integrity and structural aspect of the product. The difference of ride quality of a Venge, and the FM098, will be similar since they use the exact geometry on nearly every size. But how the bike handles/ride/takes bumps etc..might be slightly different. It is hard to say without having both bikes built identically, except with different frames, to determine that. Giving an example of a Cervelo R5ca is an extreme example. There are very few companies that have a product like that. They hand lay up those frames in CA by a few select people with expertise and some unique techniques, and produce them in a very extreme limited quantity. Like 100 I believe. Same with the McClaren Venge. If people don't want an open mold frame, then don't buy it. That simple. But claiming there are such huge differences between your typical big name frame and an open mold one is a bit misguided and uninformed. Doesn't mean there aren't open molds that are junk and not good, but typically, they have proven over time to be just as reliable as any big name brand. [/QUOTE]
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