First build. Question about propeller vs motor

[Alex1nk]

I've got a question about closing a motor and propeller. The propellers I chose are 8"x5.5, and I'm wondering if the RCX RS2206(v3) would work on with these props. I'm also going with a 210 mm frame and what to know if I'll have enough torque and thrust. Not fully decided on other parts yet except for the audrino one micro controller.

Edit: I now have another question. For this motor http://www.myrcmart.com/product_info.php?products_id=11239
will I need 30A or 40A ESCs?

Thanks

 

[mozquito1]

I don think them 8" props will fit on a 210 frame. I got a 210 & with 5" props there is only a few mm clearance. I can just about get 6" on a 250 frame.

 

[Matt Najjar]

hey Alex, I agree with mozquito - for 210 it's best to go with 5" props.

 

[Matt Najjar]

as this is your first build, try finding some online guides that feature balanced components

 

[Matt Najjar]

did you already ordered the parts?

 

[Alex1nk]

I don think them 8" props will fit on a 210 frame. I got a 210 & with 5" props there is only a few mm clearance. I can just about get 6" on a 250 frame.

Yea I kinda figured. Thanks

did you already ordered the parts?

Nope, thankfully

 

[Alex1nk]

as this is your first build, try finding some online guides that feature balanced components

I will thank you

 

[mozquito1]

If your running 4S battery 20amp esc are fine. 5 or 6S 30+ amps.

 

[Matt Najjar]

Check out these guides, hope it helps:

http://dronenodes.com/fpv-racing-drones/#tab-con-6
https://oscarliang.com/250-mini-quad-part-list-fp/

 

[mozquito1]

If your learning get the cheapest props even if 2 blade. There is not a massive difference we'll tri blades have a bit more bite on the turns they are faster . But if you got Money to burn go for them. I bought 20 sets of Dal v2 cyclones & I nearly ran out. Good props. Can't get hold of any emax Avans yet here. So will get some racekraft 5051's to try.

 

[mozquito1]

From your original post, that motor would spin that 8" prop fine if on a big enough frame.

 

[Alex1nk]

From your original post, that motor would spin that 8" prop fine if on a big enough frame.

May I ask what size of frame would you recommend?

 

[Alex1nk]

If your running 4S battery 20amp esc are fine. 5 or 6S 30+ amps.

Thanks for clearing that up. So how exactly does motor current draw affect the ESCs you use, wouldn't the ESCs need to match or be slightly over the motor requirement so that they don't overheat?

 

[mozquito1]

I ain't no boffin but I been building & flying about 16 months now.
I have only ever used 2 brand of motors dys & emax red bottoms. And 2 brand of esc,
Littlebee 20a & pocket rocket 20amp.
Nothing overheats, nothing has ever failed. I been running the same esc on all quads for 7months. My most potent batteries are chaos lab 95-150C it all comes down cold. So all them YouTube videos I watched on all different thing regarding this hobby was good advice.
As for a size of frame for 8.5" props,
You would be looking at a 500mm.
8.5x2=43cm then allow for the body.
Half a meter corner to corner.

 

[mozquito1]

If you buy a 20a esc it's rated for just that but they also state that they can be given a short 7-10 second burst of upto 25-27a.
Anymore is not good for the battery.
So although an esc is 20amp you could probably fly the whole pack for 5min at 22-23amps so basically you can go over a bit but not for long. In 7-10 seconds I can be 300' high so that's more than enough punch. I only use 3-4 seconds of full throttle. No need to hang time all day.

 

[RedSun]

I think 30A ESCs is OK, recommend you use this 30A ESC.