Building a Cam
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This tri at my school I chose to take manufacturing with metals as my elective. We pretty much have free reign over what we get to build, so I decided to build a cam (won't actually use it of course). Yesterday I ordered the Aluminum (6061) and a took apart a gear4rocks cam (scarily easy) to salvage the axel and springs. When the aluminum arrives I will start building and keep this post updated with pics, etc. If all goes well, I hope to end up with a rigid stem cam with a range slightly smaller than a number 2 camalot. |
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Do you have access to a Lathe and/or a 4-axis CNC machine? I am a BSME / MS Metallurgy, I don't see any reason you can't build a cam I would climb on. What type of mechanical test equipment do you have access to, an Instron or MTS? |
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I can see scavenging the springs, but why the axle? |
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Yup. |
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Sounds fun... think big. Go for a 36 inch span if you can..protect those nasty chimney moves. |
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We climbed the wide pitch on Blocktop with home-made cams, thanks to Greg D. Greg is a master and machined two #8 cams in 1983. I stacked them with wood blocks on pitch four. The pitch goes free now but we never would have nailed the FA without Gregs cams. To shape the cams (lobes) Greg simply drew rays from the axle and then extended the rays beyond the #4 Friend's lobes until he thought he had the dimension we needed. He did well. |
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A 16yr old kid building a cam. |
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Hey everyone, thanks for the replies! Pretty psyched to get working on this. |
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Good luck Kevin. |
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UPDATE: |
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looks big from that view...dimensions please? |
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sorry, forgot. dimensions right now are 5.5 inches long by 3/8 inches thick by 1/2 inches tall. Will probably change a bit though after sanding. |
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are you wearing climbing shoes in metal shop? haha |
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UPDATE: |
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Nice work bro! Keep the updates going! I'm excited to see how your cam turns out! |
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this is awesome! |
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Cool project! |
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Just FYI, Kevin- when slotting on the mill you're best off first using a smaller size endmill to get the bulk of the material out and then finishing with the final size endmill or (better yet) keep using the smaller endmill and offset the work to either side to achieve finish size. Less force on the cutter this way and you'll hold better tolerances. Oh, and there's no need to slot full depth in one pass... fossana wrote:Came across this 2009 link to Trango's homemade cam comp. Maybe they should resurrect a 2012 version.Chances of RC doing that are basically 0, unless they can find someone else with test equipment willing to donate the ~100 hours it took for me to run it in 2009. I simply don't have that much free time anymore, and gave up on RC. Btw, It fell through in 2010 when the sponsor went goofy and DDT didn't seem to have any interest in finding another. Not that he bothered to tell me until right when the comp was supposed to start and I had spent 2 months talking it up/finding people to compete.... Sigh. RC really was a better place under J_ung's rule, and he and I had a blast with the 2009 comp. |
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Aric Datesman wrote:...there's no need to slot full depth in one pass.ditto. I was cutting 0.015" passes with a 0.125" end mill. |
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Looks like you are making some good progress. |
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Aric Datesman wrote: Btw, It fell through in 2010 when the sponsor went goofy and DDT didn't seem to have any interest in finding another. Not that he bothered to tell me until right when the comp was supposed to start and I had spent 2 months talking it up/finding people to compete.... Sigh. RC really was a better place under J_ung's rule, and he and I had a blast with the 2009 comp.Fell through, I think not, I was clearly the winner of the 2010 Homemade cam comp (even if it was by default since I was the only contestant;). |