First quadcopter self building

[Sebastian6600]

Hi to everybody,
Actually from about an year am using an RC Hely and now I want to build a quadcopter from zero.
I have enough dexterity with these things and the assembly would not be a problem at all, the only thing that gives me a little 'anxiety is the fact if really work!
First I look around on web on project based on Arduino Uno( I have it already ) but I decided to use a MultiWII board.

Considering I'm new to these word, after hours of searching and studying different typologies I write down this material list:

MAIN CARD: MultiWII Atmega32U4
FRAME: Hobbyking Q450mm V3 ( Initially I wanted to built it from myself but they are not so expensive so.. )

MOTORS: 4x HexTronic DT700 Brushless

ESC: 4x Hobbyking 20A 3A UBEC with HobbyKing programmer

PROPELLER: 1x 12x3.8Turnigy CW and 2x CCW

LIPO: 1x ZIPPY 5000mAh 3S1P 20C

CHARGER: Hobbyking 174DC 4S 30w

RADIO: Turnigy 9X V2 with 8ch receiver

I read a lot of pro for the MultiWii, also for the GPS connector( maybe in future).
For the Radio I choose the Turnigy 9X because it don't cost a lot and I can use it in future project.

What you think about it? Wrong materials or I have forget something(omitting various wires and connectors)?
And for last, I choose this medium size because I'll attach in future a video-camera(without put on to much heavy)

 

[Andrew_Hamblyn]

In my limited experience, my one bit of advice I could offer would be bin the prop drives - everything I have ever read or seen about those motors is bad news...

Go for something like the 2836's 950kv
http://www.hobbyking.com/hobbyking/..._D2836_9_950KV_Brushless_Outrunner_Motor.html

or the 750's
http://www.hobbyking.com/hobbyking/...D2836_11_750KV_Brushless_Outrunner_Motor.html

IIRC the saying goes "Friends dont let friends buy prop drives"

Drew

 

[Sebastian6600]

In my limited experience, my one bit of advice I could offer would be bin the prop drives - everything I have ever read or seen about those motors is bad news...

Go for something like the 2836's 950kv
http://www.hobbyking.com/hobbyking/..._D2836_9_950KV_Brushless_Outrunner_Motor.html

or the 750's
http://www.hobbyking.com/hobbyking/...D2836_11_750KV_Brushless_Outrunner_Motor.html

IIRC the saying goes "Friends dont let friends buy prop drives"

Drew

Thank you very much

 

[Sebastian6600]

I read that the frame Hobbyking Fiberglass 500mm is very fragile so I choose another one more solid Hobbyking SK450 with spares parts.
Motors: Turnigy D2836/9 950KV
Added a Power Distribution Board
Changed the Hobbyking SS 25-30A with Hobby King 30A ESC 3A UBEC with HobbyKing ESC Programming Card

Some M3x8 Nylon Screws, 5.6mm x 14mm M3 Nylon Threaded Spacer, Heat Shrink Tube, Pure-Silicone Wire 20AWG, HXT 3.5mm Gold Connector w/ Protector, NylonXT60 Connectors_Male_Female_5_pairs

 

[Cyberdactyl]

I read that the frame Hobbyking Fiberglass 500mm is very fragile so I choose another one more solid Hobbyking SK450 with spares parts.
Motors: Turnigy D2836/9 950KV

Hi Sebastian. Unless you prefer the B&W and the ball on a wire look of that quad, I would highly suggest the Q450 V3.

It has the integrated PCB plate and V3 has been beefed up and improved around the motor mounts. My brother has it, and it is possibly the best quad frame bargain at HK at $14.

 

[Sebastian6600]

Heard other suggestion that DT 700 motors will be perfect with my project but with a 3000mAh lipo 3S 20C will have a discharge limit of 60A and I read that it's better to have a output over 100A with these motors. I 5000mAh 3S1P 20C Lipo with 100A will be perfect?

 

[Craftydan]

Sebastian,

How many of these DT700's do you plan to run? Rated max curent is 13A, and if you're propped to pull 25A/ea, you're going to have 4 little smoke generators.

That being said, flying packs with higher C rating than you need will give you a more even discharge curve (less voltage sag as you approach the end of the battery) but with the power draw you're expecting and that pack size, you'll see more benefit bumping up from 20C to 25C (75A) than you will 25C to 30C (90A).

It's your choice, though, since you're paying the bill.

 

[Sebastian6600]

Sebastian,

How many of these DT700's do you plan to run? Rated max curent is 13A, and if you're propped to pull 25A/ea, you're going to have 4 little smoke generators.

That being said, flying packs with higher C rating than you need will give you a more even discharge curve (less voltage sag as you approach the end of the battery) but with the power draw you're expecting and that pack size, you'll see more benefit bumping up from 20C to 25C (75A) than you will 25C to 30C (90A).

It's your choice, though, since you're paying the bill.

I'll use 4 DT700. So what you suggest? Sorry but I'm new to this subject so I need a lot of tips and help

 

[Craftydan]

The motor is fine if you're looking for a lifting quad (for a medium sized camera or the like) -- there are better out there, but hard to recommend without knowing what you want to do with it, which you probably won't know until you've played with it for a while.

My comment is on getting a high C-rated battery -- above the minimum is ok, a little more than the minimum is good, a lot more than the minimum and you're beginning to add weight and cost for no benefit.

 

[William A]

I'd drop that prop size down some also.

I use to run 11X4 and have dropped to 10X4 on the DT700 myself.

 

[mac_the_knife]

I'd drop that prop size down some also.

I use to run 11X4 and have dropped to 10X4 on the DT700 myself.

I run 10x4.5's on the DT750 and they seem to perform well. I have the SK450 frame and have been a little disappointed. Broke an arm on the third flight dropping from about 3' onto grass. A little 5 minute epoxy and some bracing on the side and it is back in action. Just won't win any beauty contests.

 

[Sebastian6600]

Actually I don't know what I'll do with my quadcopter but buying 10x4,7 props isn't a problem, they are cheaper so I can buy bigger in case.
For the Lipo a 5000mAh 3S 25C is better or a <5000mAh 3S 30C?

 

[Craftydan]

Actually I don't know what I'll do with my quadcopter but buying 10x4,7 props isn't a problem, they are cheaper so I can buy bigger in case.
For the Lipo a 5000mAh 3S 25C is better or a <5000mAh 3S 30C?

With your heli experience, you're ahead of the game, but few builders truly know how they want to lean with their first build. as long as it's not a super-expensive build, that's not a bad thing.

The gear you're spec'ing is on the heavy side (meaning bigger quad, not overweight) which will lean stronger toward a light camera-ship if you keep optimizing in this direction. It won't be perfect or the ideal quad -- you'll likely make another better multirotor if you like this nitch -- but it'll be good for you to transfer your heli-skills over to something that flys a little for you, and a starting point for you to explore the nitch.


In heli's, did you fly more scale or 3D/stunt? (if you hadn't gotten that far yet, what inspired you more?)


As far as the battery, think "max motor current x 4 < C x mAh". a little "<" is ok, a little more is great, a lot more remains only great, but costs and weighs more -- finding the minimum C rating sold that you can use then bumping up to the next C rating is not a bad strategy.

 

[Sebastian6600]

I used for about an year an RC Helicopter but when I try my friend quadcopter I fall in love
Well I'm sure I want in future to put on a camera and maybe FPV so that's because I want to build a medium size quadcopter for future improvement.
So in my case with the DT700 x4=52A. I Don't want to buy too expensive battery or to heavy so I think I'll buy a 2200mAh 3S 45C. It's isn't to heavy and have barely 100A. Hope is a good reasoning.