How to make carbon tube ?

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How to make carbon tube ?

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carbonfibreworks	carbonfibreworks posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 292, Visits: 4.5K	I need to make some carbon tube and suspect i need to make a mandrel in the lathe to lay the carbon over, what would be the best material for the mandrel ? i have some nylon and alloy bar, would i have any release issues ? Thanks in anticipation Chris
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Matthieu Libeert	Matthieu Libeert posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	there are several ways to do this. I quickly tested this system: - PVC tube cut in to halves (horizontal) - inner biketyre with releaseagent on it - put carbon around half slightly blown up tyre - put it in the pvc tube - close everything with ducttape - blow up tyre Got some good testresults but not perfect, need to perfect it, if I find the time. you could also work from the outside with some shrinktape: - Take a tube - Lay CF around it - Tighten it with some shrinktape - Heat the tape - Tape will shrink and add pressure - Remove tape - Give it a quick sand Its harder to get a perfect thickness and smooth finish over the entire tube You could work with a Silicone core: - take a tube - Cut it in half (horizontal) - Give it some thickness on the inside (thickness of CF) - pour silicone on the inside - Let it cure - Remove Silicone core and thickness you've added - wrap Prepreg for example around the core - Put it in the tube - Close the tube (with some clamps or rope or something else - Put it in the oven - Silicone core will expand and prepreg will cure. - Remove core - You have your tube Haven't found the right expanding silicone yet You could take a pvc-tube with inner and outerbag and vacuum it: - Like with the biketyre - Instead of adding pressure with a manual pump you vacuumbag the outer bag - This results in the innerbag expanding (like experiment with balloon or egg in a vacuumbox) - let it cure - Remove inner and outer bag - open to halves of the mouldtube Haven't tested my theory out yet but this might give you some ideas Hope this helps you a bit, maybe other guys on the forum have more/better ideas Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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carbonfibreworks	carbonfibreworks posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Many thanks for the reply, i will give it a try over the week end. Chris
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prsw	prsw posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 112, Visits: 1K	Any news on this interesting topic? http://motoform.blogspot.se
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carbonfibreworks	carbonfibreworks posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Hi I made a mandrel out of alloy bar in the lathe then wetted out some pro finish carbon cloth then put 8 layers around the mandrel and wrapped it with heat shrink tape, the results ? well could do better i ended up with voids between the layers and i think using the pro finish did not help. I will try again this weekend with normal carbon cloth. Chris
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wozza	wozza posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Hi, it took me a few attempts to get it right Are you wrapping the 8 layers in one length? or individual ones? Are you wetting the cloth as you wrap? or trying to wet all eight layers in one go? Are you applying heat after you apply the tape? I found no difference between pro and standard cloth. Regards Warren Carbon Copies Ltd
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carbonfibreworks	carbonfibreworks posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Hi Warren All layers in one go and wet, the product on the back of the pro finish was making it unwind if that makes sense, it did not help that the tube dia is quite small. I will have another play over the weekend and as the dia is small i am not creating too much scrap. Chris
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wozza	wozza posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Hi Chris. I find it better to wet each layer as you wind. Once all the cloth is on give the whole thing another good wetting. Literally dripping off. Then wrap the Shrink Tape round overlapping about half the tape width. (the messy bit) Then go over the whole tube with a heat gun/hair dryer.( put masking tape where the shrink tape starts and finishes otherwise the heat will cause it to unwind) You will see the tape contract and the excess resin squeeze out. I find the braided sleeve good for small OD tubes but it aint cheap. Hope that helps. Warren Carbon Copies Ltd
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wozza	wozza posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Did you get chance to have another go over the weekend? Carbon Copies Ltd
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carbonfibreworks	carbonfibreworks posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Hi Warren No i had a race seat that i needed to finish off, hope to have a try again one eve during the week. The good news is that i did finish the race seat, it was for a 250cc classic race bike and weighed in at 215 grams
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