My first hobby grade build.

[Chuck]

I've settled on the motors for my first build. They will be brishless replacements for the DJI Phantom 1, 2, and 3. I've ordered some off eBay, which should arrive within the next couple of weeks. It has come to my attention that the Phantoms use an 11.1VDC battery. I have several 7.4VDC 2500mah lipo batteries that I've been using on my JJRC H25G quads. Will these motors run on a lower voltage than 11.1VDC? I'm not opposed to buying the higher voltage batteries, but would rather be able to use my current ones for the rest of their useful lives before disposing of them.

 

[rosco11]

a. what are you trying to build?

Camera ship? racer? Both of which do not lend well to DJI anything. DJI equipment is very proprietary. Even the little things you do not expect like the coating they put on their motor wires that make them very difficult to solder. You have to scrape the coating off to get solder to stick. If you are building a custom quad, you want to get away from anything DJI. They make great drones, but they spent a lot of time and money to make sure their parts only work with their intended quads. Kind of like apple. It is why i have andriod. That solves your battery problem.

Motors.

Again what is their intended purpose? They should be the last thing you decide on. The first is the type of ship you want to end up with. Then the frame. Then the power, ie, 3s-4s-6s. Notice i left out 2s? Why would you bother? Then the flight controller. THEN the motors. After that, the esc's. Camera equipment should be last and again very dependent on the frame. We discussed the coating on the wires for the DJI motors. The selection of motors when you get away from DJI is HUGE and significantly cheaper, easier to solder and many will blow the DJI motors away if you are looking for a racer. Camera ship? Just cheaper. There, lift capacity and efficiency are more important.

Most motors will run on lower voltage. They are, after all, just winding's and magnets. They will just run slower and with less thrust.

 

[GJH105775]

a. what are you trying to build?

Camera ship? racer? Both of which do not lend well to DJI anything. DJI equipment is very proprietary. Even the little things you do not expect like the coating they put on their motor wires that make them very difficult to solder. You have to scrape the coating off to get solder to stick. If you are building a custom quad, you want to get away from anything DJI. They make great drones, but they spent a lot of time and money to make sure their parts only work with their intended quads. Kind of like apple. It is why i have andriod. That solves your battery problem.

Motors.

Again what is their intended purpose? They should be the last thing you decide on. The first is the type of ship you want to end up with. Then the frame. Then the power, ie, 3s-4s-6s. Notice i left out 2s? Why would you bother? Then the flight controller. THEN the motors. After that, the esc's. Camera equipment should be last and again very dependent on the frame. We discussed the coating on the wires for the DJI motors. The selection of motors when you get away from DJI is HUGE and significantly cheaper, easier to solder and many will blow the DJI motors away if you are looking for a racer. Camera ship? Just cheaper. There, lift capacity and efficiency are more important.

Most motors will run on lower voltage. They are, after all, just winding's and magnets. They will just run slower and with less thrust.

Pretty much said everything I was going to say.

I've settled on the motors for my first build. They will be brishless replacements for the DJI Phantom 1, 2, and 3. I've ordered some off eBay, which should arrive within the next couple of weeks. It has come to my attention that the Phantoms use an 11.1VDC battery. I have several 7.4VDC 2500mah lipo batteries that I've been using on my JJRC H25G quads. Will these motors run on a lower voltage than 11.1VDC? I'm not opposed to buying the higher voltage batteries, but would rather be able to use my current ones for the rest of their useful lives before disposing of them.

For the build that those motors would best suit I'd avoid using 2S batteries, especially ones that small. You'd likely end up with a slow build that doesn't have enough overhead to lift any payload such as camera equipment. You need to get an idea on what payload you are going to be lifting (all things that are not just for flight) before you decide on an approximate total weight. After you have that we can start getting specs on parts for the flight specific parts. Being as this is your first hobby grade I'd suggest a durable racer unless you are going for a camera bird with longer flight times. If your goal is for experimental payloads like Arduino projects, Raspberry pi projects, sensory things, or wifi-pineapple then you ware going to want something closer to a camera quadcopter in the 350mm-500mm range, if you are wanting something fast and agile then certainly in the 180mm-270mm range.

 

[Chuck]

Pretty much said everything I was going to say.



For the build that those motors would best suit I'd avoid using 2S batteries, especially ones that small. You'd likely end up with a slow build that doesn't have enough overhead to lift any payload such as camera equipment. You need to get an idea on what payload you are going to be lifting (all things that are not just for flight) before you decide on an approximate total weight. After you have that we can start getting specs on parts for the flight specific parts. Being as this is your first hobby grade I'd suggest a durable racer unless you are going for a camera bird with longer flight times. If your goal is for experimental payloads like Arduino projects, Raspberry pi projects, sensory things, or wifi-pineapple then you ware going to want something closer to a camera quadcopter in the 350mm-500mm range, if you are wanting something fast and agile then certainly in the 180mm-270mm range.

I'm building a quad similar in size to a DJI Phantom, or a Syma X8. As such, it is not intended for racing as I have no interest in quad racing myself. Having served as a combat crew member on USAF heavy bombers (specifically the B-52G), my interest is more in maximum distance, maximum flight time, and possibly carrying a camera. So aerobatics and extreme speeds aren't in the flight plan. One reason for wanting to reuse the 7.4VDC batteries is that I'm not looking for maximum power initially. While I'm learning this build's capabilities, I want to "dial it back" to avoid unrecoverable maneuvers. Much as with full scale military aircraft, where later versions of a particular model have greater capacities than the prototype and early models.

 

[Chuck]

As I said. I'm not opposed to the 11.1VDC batteries. I just prefer to use up my existing ones, before buying the higher powered ones.

 

[Diven]

You just use what you like, and I think 7.4V is Ok, you can have a test, if you are not satisfied with it, you can change it.

 

[mozquito1]

Depending on what mah they are, they will be sucked dry & probably puff up.

 

[Chuck]

Depending on what mah they are, they will be sucked dry & probably puff up.

They're 2500mah that I purchased to replace original 1800mah lipos. I've even considered trying wiring two of them in parallel for 5000mah capacity.

 

[mozquito1]

You should get some time out of them in series but the first few flights I would keep an eye on them, maybe get a small battery alarm. It will fly, just under power. You may have come across Mr steele on YouTube. He put a dji on 4s.
Wow I never thought they could do that.
I think it may have been altered. But they
Where dji motors. So don't expect much power off a 2s. It will be floaty just no speed without damaging the batteries.

 

[Chuck]

You should get some time out of them in series but the first few flights I would keep an eye on them, maybe get a small battery alarm. It will fly, just under power. You may have come across Mr steele on YouTube. He put a dji on 4s.
Wow I never thought they could do that.
I think it may have been altered. But they
Where dji motors. So don't expect much power off a 2s. It will be floaty just no speed without damaging the batteries.

If it's "floaty" but maneuvers according to how it should directionally by the controller, find by me. That shows me that I have everything wired up properly before moving up to the 11.1 VDC lipos. I am a little concerned though. All of the power distribution boards, flight control boards, and receivers that I see online appear to require wire soldering to them, but have no labeling as to which connections go where.

 

[GJH105775]

If it's "floaty" but maneuvers according to how it should directionally by the controller, find by me. That shows me that I have everything wired up properly before moving up to the 11.1 VDC lipos. I am a little concerned though. All of the power distribution boards, flight control boards, and receivers that I see online appear to require wire soldering to them, but have no labeling as to which connections go where.

Generally you have to read up on it or look at the specs as to what it requires. So if it needs 5v ou can wire it up to the BEC, or if it needs 11 - 16 you can use 3S - 4S batteries. Just a couple of examples, they generally tell you what it will work with and allow you to figure out how you are going to get that.

 

[mozquito1]

I could recommend just a bog standard Matek with clean 5&12v out.
They will be marked, it's just a tiny +or-.
Usually the grounds are on the outside. On most things.
Whatever you buy if you want to post a pic I'll photoshop the details on a copy.