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11 So I finally got around to trying out the 7x5 2 blade APC composite props.
Motor BH2810
Build Chameleon 7”
Wasn’t sure what to expect but the vertical performance blew away the 7x5.6 3 blade props I’ve been using. Not sure I noticed any handling problems either. The 2 blade props seem to give a more glide feeling for lack of better words. The motors were a little warmer with the 2 blade props. The 2 blade props make a lot of noise and a funny whirring sound quality. Definitely something you don’t want if your going for stealth. Did notice a slightly longer flight time than the 3 blade props but that’s not scientific cause I think I was cruising lighter on 2 blades. What kind of experiences have you found between the different blade quantities?
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100 biblade is faster and more efficiency, its also less in balance compared to a triblade - more difficult to tune. while a the biblade has benefits, us gear struggle more to handle them.
the comparison about blades is pretty difficult, as it needs two good tunes for bot biblade and triblade to compare.
the higher performance which can give tune difficulty is needed on some kind of builds which would struggle to get enough response. the builds with the skinny 65mm blades on 1103 motors or smaller is an example where twoblade is needed to get rotor authority.
7inch quads have lower rotor authority than a 5inch in general, a 7inch gets more close in performance if used with biblades.
less blades are a benefit in general in theory, the need for low amount of blades like twoblades is determinated by the motor torq to bladeweight ratio.
you have powerfull motors, but your blades are long, you should get a benefit from biblades. it will need another tune and also another flightline. the only reason for triblades is feeling and tuneability.
i would suggest to get into tuning the build on biblades, to get an impression and the performance peak :-)
a try on lightweight carbon biblades?
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11 Interesting, I will balance these biblades and take them out for more testing. I’ve got some larger batteries coming and will do some more tests. I did like the way it flies with the biblades and think it warrants looking into. I agree with the tuning part as the motors were hotter but could be they were spinning faster and unbalanced? Not sure where to start with the tuning, cause I finally got it to fly good with triblades. Hopefully will get some more feedback on this. There’s not a whole lot of info like there is for 5” quads.
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100 more response/ rotor authority gives a need for lower pid values in comparison. it should need less p and d. you will fly higher rpms for the same amount of trust on the biblades, this can also cause hotter motors, but there is a wide wingspan between hot motors and to hot motors :-) dont mention any heat as an issue, a hard working motor is allowed to waste some energy into a bit heat xD
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