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another new freecoaster - planetary gear engagement
ediotism:
https://bmxunion.com/daily/sneak-peek-inside-the-flybikes-magneto-cassette-hub/
in comparison, Fly came out with a cassette hub that uses two magnets. the entire engagement mechanism just has one moving part.
1. i wonder if this can be adopted into a freecoaster design? (currently with this magneto hub, the two magnets ATTRACT each other to pull the "pawl ring" into the teeth)
2. aren't magnets very brittle? any sort of impact to the axle/ pegs may damage it, i don't know if they've tested it enough and how much impact the hub can withstand
3. looking at their pictures, i'm guessing the 'pawl ring' can possibly be simplified to have, say 3 'pawls' instead of the entire ring being pawls but that'd probably require a higher level of machining precision to keep it working properly
MEAT:
They don't like impacts, either structurally or magnetically. Other downside is that magnetic force falls off very quickly with distance, so in effect they're a non linear spring, in this case they'll have less force when engaged, than when the teeth are riding over each other. If it were worth doing to reduce rolling resistance, shimano or some other major manufacturer would have done it.
ediotism:
--- Quote from: MEAT on August 27, 2019, 06:50:16 AM ---Other downside is that magnetic force falls off very quickly with distance, so in effect they're a non linear spring, in this case they'll have less force when engaged, than when the teeth are riding over each other.
--- End quote ---
the two magnets have the least distance between them when the pawls are fully engaged, im guessing that'd make the attraction strongest in that state. but to prevent skipping, the magnetic force is most needed when the tips of the pawls are just touching (they'll never fully disengage because the magnets pull them together). So the magnets will have to be pretty strong, magnetically speaking
--- Quote from: MEAT on August 27, 2019, 06:50:16 AM ---If it were worth doing to reduce rolling resistance, shimano or some other major manufacturer would have done it.
--- End quote ---
i'd give them the benefit of doubt, i like seeing innovation nevertheless. it's fine when a thousand new ideas fails, since we just need one to hit it right and it changes the industry. This hub, for instance, has one single moving part only. best wank material for engineers all round amirite?
they claim they use "neomidium magnets that pretty much last forever", so i looked it up:
1. strongest permanent magnet commercially purchasable - "Neodymium magnets larger than a few cubic centimeters are strong enough to cause injuries to body parts pinched between two magnets, or a magnet and a ferrous metal surface, even causing broken bones" from wiki
2. very vulnerable to corrosion so it needs protective coatings - should be fine being inside a hub
3. very brittle - "Magnets that get too near each other can strike each other with enough force to chip and shatter the brittle magnets themselves". even if they're well protected from killing themselves via engagement, it's hard to imagine how they can withstand sudden shocks like an icepick or even slamming the end of the peg into the ground
JFax:
Isnt it the Magneto hub that they have been testing for about 10 years?
paranoidmexican:
--- Quote from: MEAT on August 08, 2019, 10:47:53 AM ---He's got fabulous hair, i trust him.
--- End quote ---
tell him he needs a haircut and he'll get dicked off
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