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600 PRO Class Electric Helicopters 600 PRO Class Electric Helicopters manufactured by Align, Tarot, SYMA, Airhog, Chaos, HK and similar.


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Old 08-28-2016, 03:26 AM   #541
Grumpy_Old_Man
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Thee 85mm blades would give you less thrust than two 95mm blades, so that would seem like a strange way to go?
If the object of the exercise is to increase the hold of the tail then I'd expect to have to use three blades of the same size as the two blade tail (95mm).. which should give a roughly 30% increase in tail thrust.
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Old 08-30-2016, 03:35 PM   #542
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Didn't bother doing any sort of calcs. Sometimes going to a three blade setup necessitates dropping a blade size. Just an off-hand suggestion made while drinking a beer and eating dinner
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Old 08-30-2016, 04:28 PM   #543
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I'm an engineer, I have to do calcs!..

A quick fag-packet calc says you would loose some tail authority with a 3 blade 85mm tail over the standard two blade 95mm tail... So it would be a step backward on a heli already short of tail authority.
Three 95mm blades would be fine i'm sure. I run two 105mm blades on mine and it works great but needs a boom stretch to be safe.
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Old 08-30-2016, 05:33 PM   #544
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On other helis with 2 bladed tail and good tail ratio and blade size, doing a 3 bladed tail conversion would normally mean to either drop the tail ratio or go down on blade size. But on the 600 we want to increase the tail authority and keeping same blade size will probably bring us right at the sweet spot of available tail thrust even for lower headspeeds. Now for guys that frequently do headspeeds of 2400+ there may be some issues on the long term with material fatigue, especially the tail gears. Either way for headspeeds that high, tail authority doesn't seem to be an issue already so maybe a 3b conversion may not be worth it in those cases (except for bling factor).
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Old 09-01-2016, 02:56 PM   #545
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Isn't there some maths/calc you can do to check main rpm, main thrust versus tail ratio, tail thrust to get a nice rpm range to fly with a secure tail all the time.

need to check that darkhorse calc...
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Old 09-01-2016, 07:42 PM   #546
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Quote:
Originally Posted by Grumpy_Old_Man View Post
I'm an engineer, I have to do calcs!..

A quick fag-packet calc says you would loose some tail authority with a 3 blade 85mm tail over the standard two blade 95mm tail... So it would be a step backward on a heli already short of tail authority.
Three 95mm blades would be fine i'm sure. I run two 105mm blades on mine and it works great but needs a boom stretch to be safe.
Me too, but after work I just don't feel like doing any more haha
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Old 09-02-2016, 06:25 PM   #547
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Is the nitro auto gear mod. being used in this config. If so could 85mm blades be used?
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Old 09-27-2016, 01:11 PM   #548
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Quote:
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Is the nitro auto gear mod. being used in this config. If so could 85mm blades be used?
I'm not sure about the nitro gears but the gears from the older ESP version have been used which speed up the tail allowing stock 95mm tails to be used at less than screaming headspeed. You wouldnt want to use 85mm tails on a 600.
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Old 09-27-2016, 04:30 PM   #549
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Quote:
Originally Posted by Grumpy_Old_Man View Post
I'm not sure about the nitro gears but the gears from the older ESP version have been used which speed up the tail allowing stock 95mm tails to be used at less than screaming headspeed. You wouldnt want to use 85mm tails on a 600.
I was thinking of a scale model with lower head speed say, 1500 rpm.
I run my 4 blade scale 600 with the nitro/esp gear ( I think they are the same ) and have to use 105mm. The tail will try to come around on a hard collective input. I found out that it doesn't like tic-tocks! It does loops and rolls nice though.
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600 PRO Class Electric Helicopters 600 PRO Class Electric Helicopters manufactured by Align, Tarot, SYMA, Airhog, Chaos, HK and similar.

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