Hi there,
I’m moving on to a large frame this time after spending way too many hours building much smaller quads.
I’ve purchased a generic ZD850 frame and Pixhawk 6C with accessories.
Now, I’ve been using ecalc extensively to find the best combo and keep getting stuck.
I am at the stage where the following is in scope:
5008 - 335KV Motors.
20,000mAh 6S
15x10" 2 bladed propellor.
This is where i’m stuck…
I’m trying to find a suitable propellor. I can easily find smaller pitch ~5.5" but not too many 10" pitch. Further, I require the bolts holes to suit the motor but very few come with them already.
My questions are:
Should I be using such an aggressive pitch? The flight time doesn’t change much if I reduce the pitch, but the distance covered at full speed drops off significantly when I drop the pitch. Distance is certainly something I want.
Is it just a case of drilling the prop to insert the bolts? I have experience drilling props for larger gas planes, but never with multirotor…
What type of prop should I opt for? Folding style, or carbon, or glass poly?
Anyone have any experience with these frames? Could I go up to to a 16" diameter prop?
What Take-off weight were you estimating? Just that battery and frame alone would be in the 3.75kg range. As I’m sure you have found with 16x5.5 (most commonly available) and 330kV motors on 6S you wouldn’t want to go heavier than ~4.3kg.
My assessment is as follows:
Frame: 1210g
6x Motor: 870g
6x ESC: 36g
6x Prop: 276g
1x Batt: 2630g
1x FC: 60g
1x Payload Dropper: 80g
1x Sonar: 40g
1x Camera: 60g
1x GPS: 25g
1x PDU: 25g
Misc Wiring: 150g
Totalling: 5,462g
Hover throttle is 52% only, 2.7 thrust/weight, 9.2km range at 88km/h.
Why do you say limit weight to 3.4kg? even with the change in prop pitch I still achieve hover at 55% throttle, but the range drops significantly by ~30% and 60km/h top speed.
Yea, you are right. I must have had a quad configured. At that weight with 1555 props and 400kV motors I see ~48% hover throttle which would be a good target.
High pitch propellers are designed for high airspeed flight (like fixed wings). Stick to the lower pitches. 1555 is a great propeller ratio between diameter and pitch.