RC India

I have decided to go ahead with the Hexacopter build. All equipment in place as follows:

1. 6 x DT 700 motors - Thanks Subhash Reddy, Esq.

2. 6 X Simon K flashed HK 20 A ESC's - Thanks Pravesh.

3. 3 X 10 X 4.5 Props

4. 3 X 10 X 4.5 R Props

5. HK KK 2.0 Control board

6. 2 X ZIPPY Flightmax 2200mAh 3S1P 20C

7. Frame made out of 10mm x 10mm Aluminium Square tube stiffened with 9mm X 9mm Pine wood dowel - Thanks Manish and Aero Engineering Works.

8. Centre plate = 2 X 9 " dia x 5 mm Plywood

9. Reptile 500 V2 Landing Skids - Thanks Arun.

10. Power Distribution Board - Thanks Girish.

Additional parts and and equipment supplied by Quadkopters and Aditya Nagar, Esq.


The Hexa will span a little more than a metre and weigh 3.5 Kgs, all inclusive.

What will this result in (a) Rocket (b) High performance Hexa (c) Standard Flyable Hexa (d) Sluggish Hexa (e) Dud - waste of time

Request all the Champions and Pundits to chip in and let me know your opinions and advice.

I need to get this ready by the 18/04/2014.

Regards.

Due to the high weight of the model it will be somewhere between C and D.
Choosing 4S instead of 3S certainly can help in reducing weight.
Or atleast use 11 inch props with 3S

If flight time is not an issue then you can use uberhigh C rating Lipos with lower capacity for better performance.
Like Nanotech 45/90C or even ASpec 65/135C (You can use even lower capacity LiPo with this one.)

Arun, Your thoughts?

Thanks for the prompt response. I don't have 4 S and don't plan to invest in it now. Alternative solutions based on 3 s LiPo's are welcome.

First of all the auw is very high in my view..
The motors are coming around 450gms
Lipo another 400gms
Esc around 120gms
Props 80gms say
Total around 1050gms
And are you going to make a 3.5kg?:o:o
That is not needed in my opinion..
Try to reduce the weight of your frame and landing gears
Or still you need to go with this build then this will be the result

Total auw 3500gms
Lipo 4400mah 3s
(Leave about c its more than enough)
Props 1045
Your flight time will be  less than 4 min in normal condition.
It will be an underpowered hexa and lift up only after 60% throttle..

What you can do to increase the flight time and performance

Keep auw below 2.5kg
Use 1147 prop and 4s lipo
Or 1245 or 47 with 3s lipo

This is from my knowledge and please correct me if I am wrong..

Thanks all. Weight reduced to 2.4 Kgs.

 {:)} sounds great VC sir,  :thumbsup: All the best
wish to have a look of your 2.4 killo Flying Monster in the air  (:|~
hope i will get a chance to visit your place soon  (:|~

You can also rethink the size of the frame, 1 meter with 10-12inch props is too big until and unless you are doing it for a specific purpose.
70cm motor to motor distance would be apt for props upto 12" with slight legroom . An image for illustrative purpose, doesn't belong to me

http://imgur.com/4UuYNzH (http://imgur.com/4UuYNzH)

had a similar config an year ago.. gave a flight time of 10 mins on 5000 mah 3s. its gonna be a performace hexa.. but u cant use it for fimling .. too much of vibrations from the motors..

VC your weight of 3.5 Kg without payload seems on higher side please rework the AUW. If you are presuming with Payload then its a sure possibility.

DT700 can take up to 12" prop on a Multirotor with 3S and can give more than a Kg Static thrust on WOT or upto 11" with 4S. Say considering safe margins you are able to pull 1.1 Kgs each. At 60% lift off you should be able to easily lift off a AUW of more than 4 Kgs.

So your Hexa is going to be agile for sure. However with just two 2200 max flight time much less than 5 Mins assuming safely it draws 8 amps each motor at lift off.

To have a prop of 11" you need to have the sides of the Hexa equal to say 13" (Adjacent motor to motor) and the diagonal is going to be 26" and The Hexa is going to have a foot print of more than 37" dia circle with all props fitted and spinning.

I think you are confused between motor to motor and total prop length.

Say if 11" props are placed next to each other horizontally, total length would be 22", where as distance between prop holes(i.e motor to motor) would be 11", because AFAIK motor to motor distance is the distance between shafts of the motor not the farthest tips of the props.
So if we take motor to motor distance as 24" as you mentioned then gap between prop tips would be 13" which is huge since usually 2/3" gap is more than enough in most cases.

Attached a really bad pic, you might get my point.

OMG!!! how the hell did I commit such a blunder. @ sidewinder you are absolutely right. Amended my earlier post.

Worst thing is I believe I am repeating this mistake for the second time and getting corrected. Earlier once in a micro quad thread. VC tells me I am no good in English now I am coming to know I am poor in maths too. :).

VC sir,

Satya sir is having some sort of cutting service for center boards, ask him to cut a center board from 2mm/3mm FRC boards( the ones used for PCB) they are stronger than plywood, and can take crash like hell, much lighter than any alternates and cheaper than CF ones. this can drastically reduce the weight. using bigger props like 12" can make the flight times longer,

i personally have seen a good improvement in stability and flight time after flashing my KK 2.1 with new firmware released by a guy named stevis(i guess. search in internet for the correct name and firmware, use lazy zero software in online mode and download the code from repositary)

Stock firmware sucks in terms of GUI and missing so many options. also not satisfied with the KK 2.0 board as you can see the soldering of the back is not promising and look like hand soldered. cannot recommend anything else as i haven't used any others. look out for APM as you will be needing all those features like compass,GPS in long run which KK 2.0 doesnt support.

Thats all ive got,
Oh i forgot to mention All the very best for your Build VC ji

Ashok.P