Monster Quad Copter which Motors and Props

[Mslater]

Hi Quadflyers,

I'm having a play with a monster quad, done some calculations for prop sizes and motors and got quite a shock on the results. I think I'm looking at 18" props on this one !!!

Just suppose I have a carbon quad copter frame, weight at 600g (Frame only), distance between adjacent motors is 930mm.

I have some choices myself but its always interesting to see if anyone has any recommendations first so..

What motors / props / Esc ???


At the moment it looks like I might need to reduce the frame size..... we'll see...

PS You are not going to believe the job NHP has done on this frame - pictures later

[Sieze2]

Hi Quadflyers,

I'm having a play with a monster quad, done some calculations for prop sizes and motors and got quite a shock on the results. I think I'm looking at 18" props on this one !!!

Just suppose I have a carbon quad copter frame, weight at 600g (Frame only), distance between adjacent motors is 930mm.

I have some choices myself but its always interesting to see if anyone has any recommendations first so..

What motors / props / Esc ???


At the moment it looks like I might need to reduce the frame size..... we'll see...

PS You are not going to believe the job NHP has done on this frame - pictures later

I had a 2.2 kg Quad all up, with about 60cm between motors, and it only needed 200w motors and 20A Esc's, and thats running 10 inch props. The most it would pull on full throttle is 12A, and it would fly vertical like a rocket! Your all up weight must be over 5kg to feel that you need 18 inch props ?!?

[jamiem]

Something that became pretty clear when I was flying my quad was that the frame didn't really weigh anything, and as such you could go much much bigger without much of a weight penalty.

I found a thrust/power calculator at the time and worked out that my motor/esc combo was about 4 times as powerful as it needed to be, from memory I think they were 200w motors, and the whole machine would have flown on 200w (or around those figures). So unless you are planning on hauling a lot of weight with it, I wouldn't go too mad.

[Lee 72]

I'm very interested to see what you decide on. I have just received my Open Pilot control board and want to build a quad capable of carrying my 600 size camera mount with SLR camera.

[Mslater]

I had a 2.2 kg Quad all up, with about 60cm between motors, and it only needed 200w motors and 20A Esc's, and thats running 10 inch props. The most it would pull on full throttle is 12A, and it would fly vertical like a rocket! Your all up weight must be over 5kg to feel that you need 18 inch props ?!?

I'm more worried about feedback to the gyros and just how much authority each prop will have.

[J3DI]

Large props will have more inertia and will affect the stability. 10 - 12inch seems to be about the maximum size props I have seen used (generally) because after this their ability to change speed quickly is reduced and hence reduced stability.