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Does the maths put you off Electronics? Check here
29 Sep 2019 11:23 #46
by crash happy
Replied by crash happy on topic Does the maths put you off Electronics? Check here
Thanks Klippy. I think the max RPM will be around 8000. Ideally I want enough power to lift a model with a wingspan of around 1800mm & all up weight of around 3 to 4 kg for a reasonable duration. It doesn't have to be fast. What I have in mind is another low wing trainer based on the Cherokee. The rational being if I use the current one as a test bed & get it flying sensibly I can scale up. 
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29 Sep 2019 14:47 #47
by Quorneng
Replied by Quorneng on topic Does the maths put you off Electronics? Check here
Provided you keep the same prop you can always use less cells without a risk of blowing anything up!
There is of course no proof that motor with that prop will draw its maximum rated amps on 6s. It will simply have to be measured.
I agree with Klippy that a 17x8 is big for 1.5 m span. I expect on 6s it was capable of hovering and that it would do so on less than full power!
A set up that would require serious flying skill and throttle control.
There is of course no proof that motor with that prop will draw its maximum rated amps on 6s. It will simply have to be measured.
I agree with Klippy that a 17x8 is big for 1.5 m span. I expect on 6s it was capable of hovering and that it would do so on less than full power!
A set up that would require serious flying skill and throttle control.
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29 Sep 2019 14:48 #48
by Quorneng
Replied by Quorneng on topic Does the maths put you off Electronics? Check here
Provided you keep the same prop you can always use less cells without a risk of blowing anything up!
There is of course no proof that motor with that prop will draw its maximum rated amps on 6s. It will simply have to be measured.
I agree with Klippy that a 17x8 is big for 1.5 m span. I expect on 6s it was capable of hovering and that it would do so on less than full power!
A set up that would require serious flying skill and throttle control.
There is of course no proof that motor with that prop will draw its maximum rated amps on 6s. It will simply have to be measured.
I agree with Klippy that a 17x8 is big for 1.5 m span. I expect on 6s it was capable of hovering and that it would do so on less than full power!
A set up that would require serious flying skill and throttle control.
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29 Sep 2019 18:08 #49
by Eric
if you are calm and collected when all about you are going berserk - you've missed something important!
Replied by Eric on topic Does the maths put you off Electronics? Check here
OOPS! My engine rev's appear to have gained 2000 rpm's at idle! 
if you are calm and collected when all about you are going berserk - you've missed something important!
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29 Sep 2019 21:22 #50
by crash happy
Replied by crash happy on topic Does the maths put you off Electronics? Check here
Quorneng wrote "I agree with Klippy that a 17x8 is big for 1.5 m span. I expect on 6s it was capable of hovering and that it would do so on less than full power!
A set up that would require serious flying skill and throttle control. "
You are not wrong Simon. I watched a video of it being flown by an expert 3D pilot, defies the laws of aerodynamics & probably physics too !
climes vertical at half throttle !
I don't think i will be attempting to fly it, way beyond my skill level. 
The parts will be useful in something large & a bit tamer though.
A set up that would require serious flying skill and throttle control. "
You are not wrong Simon. I watched a video of it being flown by an expert 3D pilot, defies the laws of aerodynamics & probably physics too !
climes vertical at half throttle !
I don't think i will be attempting to fly it, way beyond my skill level. The parts will be useful in something large & a bit tamer though.
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30 Sep 2019 08:58 #52
by crash happy
Replied by crash happy on topic Does the maths put you off Electronics? Check here
Ha Ha, you can read me like a book Klippy! I haven't even finished the Cherokee (nearly done) & i'm already thinking "how can I modify this beast to tame it down" 
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30 Sep 2019 12:10 #54
by Eric
if you are calm and collected when all about you are going berserk - you've missed something important!
Replied by Eric on topic Does the maths put you off Electronics? Check here
Confucius he say - If you don't push your limits, you don't improve - just before he crashed again! 
if you are calm and collected when all about you are going berserk - you've missed something important!
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30 Sep 2019 15:50 #57
by THE BLACKBIRD
Replied by THE BLACKBIRD on topic Does the maths put you off Electronics? Check here
I think the last time i flew a model was last Christmas day 
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01 Oct 2019 19:07 #59
by crash happy
![[badass]](/media/kunena/emoticons/bad_boys_20.gif "[badass]")
Replied by crash happy on topic Does the maths put you off Electronics? Check here
Fortunately it has a 6s 5000 mah lipo with it & a nice Turnigy touch screen charger ! I might do as you suggest & get 14x8 next time I order some bits. As far as reducing the throws, it's going to have be a lot, the control surfaces on this thing are HUGE ! I will give it a go though, after all whats the worst that can happen.Klipkopwildlife wrote: Crash, I think if you series 2 3s Lipos together, slap a 14x8 prop on and reduce the throws you should be able to fly it quite happily as it is.
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01 Oct 2019 20:26 - 01 Oct 2019 20:27 #60
by Eric
if you are calm and collected when all about you are going berserk - you've missed something important!
Replied by Eric on topic Does the maths put you off Electronics? Check here
From your description of excessive power and massive control surfaces, I suspect it is a 3D machine you have there.
It will have been designed with a rearward c of g to give it stability in the prop-hang, and snappy pitch control at low speeds, so would be a real handful to fly like that.
As suggested, cut the control throws WAY down, and re-balance it at between 25 and 30 % of the chord, apply loads of expo, then be REALLY careful on the sticks until you catch up with it!
Once you have it tamed, it should be a 'pussy-cat' but even cats can bite!
It will have been designed with a rearward c of g to give it stability in the prop-hang, and snappy pitch control at low speeds, so would be a real handful to fly like that.
As suggested, cut the control throws WAY down, and re-balance it at between 25 and 30 % of the chord, apply loads of expo, then be REALLY careful on the sticks until you catch up with it!
Once you have it tamed, it should be a 'pussy-cat' but even cats can bite!
if you are calm and collected when all about you are going berserk - you've missed something important!
Please Log in or Create an account to join the conversation.
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