Hey all, this is my first post here. I've gotten quite a bit of useful information and read many interesting things here, and finally joined. I've only recently gotten into the RC world, and my first step was to build a quadcopter.
The first step was to read up on the topic. I researched the theory behind motor output, power:weight ratios, frame types, flight controllers, prop sizes, batteries, and on. I decided to build a medium sized quad, aiming for something that'd be stable and able to carry a camera later.
My build list:
| Item | Quantity | Weight (g) per Unit | Weight (g) Total | Description |
|---|---|---|---|---|
| Frame | 1 | 425 | 425 | hk s500 glass fiber, use 9-10" props |
| Motor | 4 | 70 | 280 | Turnigy D2836, 1100kv, 1.13kg thrust, 7-11 prop |
| ESC | 1 | 112 | 112 | Qbrain 4X25A |
| Battery | 1 | 404 | 404 | Zippy 3S, 20C, 5000mah, 4mm bullet |
| Flight Controller | 1 | 32 | 44 | APM 2.6, iso case, 7N GPS |
| Props (Normal) | 1 | 17 | 17 | 11X4.7 plastic, weight per pair |
| Props (Reverse) | 1 | 17 | 17 | 11X4.7 plastic, weight per pair |
| 0 | ||||
| 0 | ||||
| 0 | ||||
| Transmitter | 1 | 0 | turnigy 9xr | |
| Transmitter Battery | 1 | 0 | turnigy, 2200mah | |
| TX Module | 1 | 13 | 13 | FrSky DJT, D8R pair |
| Battery Charger | 1 | 0 | iMAX B6AC, genuine |
YouTube Motor/Prop Test (for data, see the linked google doc in the video description)
I came out with these calculations:
| Weight of Itemized Components (g) | zip ties | Weight of Zip Tie (g) | Velcro (sq. in.) | Weight of Vecro (per sq. in., g) |
|---|---|---|---|---|
| 1312 | 16 | 1 | 6 | 2 |
| Total Weight (g) | Thrust per Motor (g) | Minimum Thrust:Weight | Suggest Max Weight (g) | Suggested max payload |
| 1340 | 1130 | 2 | 2260 | 920 |
It seemed all good, so I ordered parts.
First majour (more than prop damage) crash:
Reassembled, some things moved around:
Relocated the battery to free up the camera mount, and covered some wiring:
Replies
It flies fairly stably, though I'm still correcting the drift- I need to save the trims from my radio next time I take him out. It's fairly responsive, almost twitchy. My longest cumulative flight time on a charge has been :35, and it dropped from 12.6V resting (3S, 5AH LiPo) to 11V, so there was some time left. I haven't done any GPS-based activities yet, as my 'ground station' is a desktop. I'm just getting into photography and acrobatic maneuvers, and will be getting an FPV system very soon.
As a newcomer, I'd have built a smaller quad if I had it to do over. I wanted to have the capacity for a camera and whatnot with a larger craft, but I think I would have been happier flying something smaller and more maneuverable to learn on.