Motor help

Deciding on a motor for an av build. The auw is just under 2600 g. I was looking at 2 options. One on the lower end and the other on the upper end. Using 15" props. The Sunnysky 3508 380kv or the T-motor Antigravity 4006. Both are in budget but the T-motor is stretching it and I will probably have to forgo some extra options till later. Is the T-motor significantly better or are the differences minimal? And if significant, what are they?


http://www.buddyrc.com/sunnysky-v3508-29-380kv.html

http://www.rctigermotor.com/html/2015/Antigravity_Motors_0212/289.html
 

Motopreserve

Drone Enthusiast
I determine the motor (and all components) based on the camera. For instance, if by AP you are referring to a fairly inexpensive GoPro rig. Then the sunnysky would be more than capable. If you are planning on hauling a Canon 5D, the tried and true T-Motor or KDE might be your best choice.

I have had good luck with that same SS motor, but in the 580kv configuration. It's on a tarot 680 Pro built for long flight times that only lifts a GoPro with gimbal. I've also used several other SS motors, both X and V series, all with good luck.

I have a heavy lifter that I run KDE on. Great craftsmanship, 3rd bearing, collar instead of circlip for shaft security etc. Its definitely a step up from the Sunnysky.

The higher quality motors are going to offer added efficiency, and peace of mind. But the cost difference is significant.

Not sure if my logic is sound, but I figure the extra confidence I have with the higher quality motor makes sense for me on the much more expensive rig/camera.
 

Make sense. It will only be carrying a gimbal and gopro. I notice the efficiency on the SS is better or am I not looking at it correctly?

I've seen pics of motors that had props on top and bottom. How do those perform?
 

Motopreserve

Drone Enthusiast
It's hard to tell - because all the companies list/test differently. But the SS are good motors, especially considering the price.

I'm not aware of single motors that are coaxial - but there are MRs designed to carry 2 motors per mount/boom. They are called X8 (opposed to flat 8). They have more lift than a quad obviously, but less efficient than a flat 8 due to one prop being effect by the other.

What's the frame you'll be using?
 

Very similar frame actually. Tarot 650 ironman. What gimbal are you using?



It's hard to tell - because all the companies list/test differently. But the SS are good motors, especially considering the price.

I'm not aware of single motors that are coaxial - but there are MRs designed to carry 2 motors per mount/boom. They are called X8 (opposed to flat 8). They have more lift than a quad obviously, but less efficient than a flat 8 due to one prop being effect by the other.

What's the frame you'll be using?
 



Motopreserve

Drone Enthusiast
I would say the DJI that's used was better than the T-2D. I had a couple hiccups early on and then it was pretty solid after that.

The newest is just the gopro4 version of the 3 axis. The only bad thing I head about the 3 axis was the tilt function control from the radio wasn't as smooth. There are ways around that at the radio side - if they haven't fixed it with this latest release.
 

Which esc do you like? I'be heard good things about the ones from rotorgeeks. Even have a vid driving something like 20A through a 12A esc and it powered down automatically. I'll prob go for the SS motor. Will a 30A esc suffice?

Also what brand props? Is there a real difference in brands if ur getting carbon fiber?
 

Btw, do you know if the h4 3d from a phantom can be retrofitted to work on a non DJI copter? Or would I still need a GCU. Reason I ask is because I see a few a couple of phantoms listed on Craigslist for parts because they were damaged. Wondering if the gimbal is worth salvaging.



I would say the DJI that's used was better than the T-2D. I had a couple hiccups early on and then it was pretty solid after that.

The newest is just the gopro4 version of the 3 axis. The only bad thing I head about the 3 axis was the tilt function control from the radio wasn't as smooth. There are ways around that at the radio side - if they haven't fixed it with this latest release.
 

Motopreserve

Drone Enthusiast
The ESCs with a given motor, coupled with a flight controller, can be an issue. I had problems with the XAircraft superx and these SS motors using hobbywing ESCs. Same setup, no issue with the Naza FC instead. So make sure you do some research for people using all your exact components.

There were some issues with simonk and pancake motors. I haven't read up on that in a while.

I'm running ZTW spider 30A ESCs now. No issues with either Superx or Naza. You need to check that SS data sheet and see the highest amperage you'd be pulling to determine the correct capacity ESC.

You need to get the GCU to make the older phantom gimbals work, but I dont know if that works for the newest ones. Should though.

Also, there is a difference (huge in fact) between CF props. The nice ones are easy to balance, the cheap ones are harder to balance. Performance wise, I think original and knock-off are probably close if they are knock-offs of a specific prop.

You should probably get some APC props to test and practice with before moving to CF. The CF are much more expensive to replace if you have an early mishap.
 
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Which propeller brands are the better ones? Which are medium grade?

Also are Simon-k programmed esc a must?



The ESCs with a given motor, coupled with a flight controller, can be an issue. I had problems with the XAircraft superx and these SS motors using hobbywing ESCs. Same setup, no issue with the Naza FC instead. So make sure you do some research for people using all your exact components.

There were some issues with simonk and pancake motors. I haven't read up on that in a while.

I'm running ZTW spider 30A ESCs now. No issues with either Superx or Naza. You need to check that SS data sheet and see the highest amperage you'd be pulling to determine the correct capacity ESC.

You need to get the GCU to make the older phantom gimbals work, but I dont know if that works for the newest ones. Should though.

Also, there is a difference (huge in fact) between CF props. The nice ones are easy to balance, the cheap ones are harder to balance. Performance wise, I think original and knock-off are probably close if they are knock-offs of a specific prop.

You should probably get some APC props to test and practice with before moving to CF. The CF are much more expensive to replace if you have an early mishap.
 
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Motopreserve

Drone Enthusiast
The top of the line CF props are t-Motors. Most others are a knock-offs of those. I have tried several different ones, and I couldn't tell you the names of any of the others. I think Tarot makes one model.

You can find them at places like rangevideo.com, AddictiveRC, and probably gotheli (sponsor here). They have all required a lot of balancing. But the cost saving has been significant.

SimonK is what you're looking for, unless you have one of the ESCs with proprietary firmware made specifically for Multirotors (like KDE and Castle Creations do). There is also BLHeli firmware. You'll have to read up on the differences.

But I think you'll find simonK to be ubiquitous in the industry now. You used to have to flash them yourself. I'll probably never use that tool again! :)
 

What is your preferred method for balancing a prop? Sanding the edge? Sanding face? Tape? Paint? ...........


If sanding, do you sand the entire length of the heavier side?
 
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Motopreserve

Drone Enthusiast
For the basic balancing, I personally sand the "meat" (center) of the underside of the blade. Then some work on the hub for vertical balance. I typically use CA for that - although I've flirted with filing off a bit of the imbalance is drastic. I bounce back and forth making sure one doesn't throw the other off.

There are some tricks to finding where on the blade there may need some additional tweaks, for instance sanding a bit more toward leading or trailing edge.
 

What do you mean by vertical balancing?

Any good comprehensive vids on the subject?


For the basic balancing, I personally sand the "meat" (center) of the underside of the blade. Then some work on the hub for vertical balance. I typically use CA for that - although I've flirted with filing off a bit of the imbalance is drastic. I bounce back and forth making sure one doesn't throw the other off.

There are some tricks to finding where on the blade there may need some additional tweaks, for instance sanding a bit more toward leading or trailing edge.
 

Motopreserve

Drone Enthusiast
After balancing the blades, which is easiest by letting the prop hang in the horizontal position on the balancer, you then place the blades directly vertical. If the prop falls to one side or another - the hub balance is off. The side that rests toward the floor is the heavy side.

Adding some CA (or removing a hair - which is more difficult with T-Motor style 3-hole props) will balance the hub.

End result should be perfectly still no matter where you place the prop 360 degrees. If a blade or hub is still not balance, the prop will move. I start with straight horizontal and vertical balance, and as I get closer, start testing at 2 o'clock, 5 o,clock, 8 o'clock etc. it should remain where you leave it once it's perfect.

The other way to balance the blade is to add scotch tape. That has the advantage of being able to remove again. Once sanded, no putting that back :)

Practice makes the whole process quicker. You get a feel for how much to add/remove based on the movement of the prop. I dread it less now...but only a little less :)
 

Can the h3 3d be used directly with a non phantom copter but still using a naza v2? Or do you need a GCU?



I would say the DJI that's used was better than the T-2D. I had a couple hiccups early on and then it was pretty solid after that.

The newest is just the gopro4 version of the 3 axis. The only bad thing I head about the 3 axis was the tilt function control from the radio wasn't as smooth. There are ways around that at the radio side - if they haven't fixed it with this latest release.
 
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