Bicycle frame

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Bicycle frame

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brummelisa	brummelisa posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 20, Visits: 144	Kylle, Since I have only tested a plug I know the pro and cons with that. And with a plug I mean that you make the piece you want first in extruded polystyrene (you use it in when you build houses). You can cut it with a hot wire (I made mine from a guitar-coard (correct word?) and used a car-battery-charger. It's like cutting cheese. The only tough part is that you have to have some sort of guideline that you cut after. Then you simply wrap the piece with CF and you are ready to go. If you want to remove the polystyrene you just simply poor acetone and it will melt. You don't make the whole monocoque in one piece, but you have to glue them together and that can be a bit tricky, but is not that hard. This guy used the above technique http://theprojectjunkie.com/composite-bicycles/homemade-carbon-fiber-bike-project.html You can naturally also create a mould, but I felt that it's too hard work for me to make one and specially since I will only make one bike, I felt that it was too much labor. But I think the end-result would be much easier to put together if you use a mould. Thanks for the geometry. When I decided to start my bike, the P5 was just announced and I thought it was so beautiful that I decided to copy it. I was lucky that the geometry was posted at Cervelo's webpage and I could grab some photos that I could measure from (and it was easy to make it correct since I could have the geometry as guide so I knew how much I had to increase the photo to make it 1:1 Please ask me any more questions you have. I have included a photo of the seattube just to let you know how I included my seatpost-holder. I wrapped some CF around my seatpost and then I glued it into my polystyrene and after that I wrapped some more layers around it.
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kylle	kylle posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 101	what building method do U suggest for a MTB 29'er frame? the original idea is to do a monocoque front triangle and assembly the rear triangle using the same method that U'r using... I don't understand when U say plug ? It's maybe my English or I don't know the method.... don't know if it help's but the geometry on p5 will be something like this: Cervélo's sizing system is one of the best even their top notch riders ride whit stock frame size's
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Joe	Joe posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 310, Visits: 1.5K	Awesome. Cant wait to see the finished bike !!! A $1000 electronic device will always protect a 10 cents fuse
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Matthieu Libeert	Matthieu Libeert posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	looks great keep up the good work! Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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brummelisa	brummelisa posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 20, Visits: 144	Thanks Kylle. I can unfortunately not show the mould, since I didn't use any mould when I made it. I simply made plug for each part and wrapped CF around it. Yes, I made integrated headset and that was really tough. The reason is not only that it had to be perfectly aligned, but the fork was tapered. I used my headsets to act as a mould and mounted them on the fork so they were aligned. It took several days and tries to make it perfect. Right now, the headtube looks a bit ugly on the outside, but I will put some nice layers at the end. Since I don't have a P5 around me I simply used a photo in Photoshop to measure all the measurements. I agree that the chain stay looks a bit short, but I think it was just the photo. Here you see an earlier photo with the wheels.
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kylle	kylle posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 101	I sell Cervelo's for a living!!! and that's right on the spot! perfect!! can u show the mould of the top tube? did u do integrated headset? it's maybe the picture but it seems the chain line is a bit to short!!
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Joe	Joe posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 310, Visits: 1.5K	Looks awesome. Good luck for the next steps A $1000 electronic device will always protect a 10 cents fuse
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brummelisa	brummelisa posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 20, Visits: 144	Yes, it's tricky, but this is the result so far. I wish I took more photos during the build, but I thought building was more fun than documentary it The next stage is to wrap several layers of CF around the joints
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kylle	kylle posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 101	brummelisa (28/02/2012) I'm also planning to build a bike (tt frame that looks like Cervelo P5). Sure, it's lot to do and think about, but it's fun Anyway, I have found some other links that may be nice to see http://fairwheelbikes.com/forum/viewtopic.php?t=6655 http://fairwheelbikes.com/forum/viewtopic.php?f=6&t=7194 http://fairwheelbikes.com/forum/viewtopic.php?f=6&t=7602 / Marcus I tink that kind of frame "monocoque" style its triky but doable at home...
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mhdghoul	mhdghoul posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 113	i do 1 thing for sure i know it will be very strong in bonding 1st i bond the 2 parts with epoxy (the two mixture tubes ) i prefer alteco or abro or whatever , i just align the two parts and stick them with papertape and leave the parts where i want to put the epoxy not covered then i add epoxy to exactly look like small dots and leave it till its done , after that i take of the paper tape and see if it was aligned perfectly if not i break the spots and try again if it is good ( this process is to stick the two parts together aligned only . the next step is to mix resin with cf cut into very small pieces (usually use left over for that) and it will look like fiber putty then i add the caatalist to it and fill the area between the two parts , this will make it very stong and the next day i sand it with a grinder to the shape and when u finish the part it will not be something od cause its the same exact color and its cf at the end . best regards mhd alghoul mhdghoul@hotmail.com youtube channel :atmospherejo link is http://www.youtube.com/user/atmospherejo?ob=0&feature=results_main
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