Motor Questions

U

Upchukar

New Member
Hello Everyone,

I purchased 4 pack of EMAX 2213 935Kv motors off of Amazon for my first drone build. Iwhen they arrived I noticed that all four have CW threaded shafts. Is this a problem? Should I return them and get two CW and two CCW?

Also when I turn the motor housings they rotate kind of bumpy. I assume this is normal due to the magnets interacting with the coils. Is this normal or should they rotate smoothly?
 

John Doecliff

John Doecliff

Member
That's typical. They do make CW and CCW shafts like you mentioned but not all manufacturers offer them. You usually see them in the higher speed motors for racing quads. You definitely want to use a "nylock" style locking nut or something to that affect. I have a hex that's the same way and have never had a problem with my props becoming loose. The bumpy feel due to the magnets is normal as well.
 

theGreenOrange

theGreenOrange

Member
Upchukar said:
Hello Everyone,

I purchased 4 pack of EMAX 2213 935Kv motors off of Amazon for my first drone build. Iwhen they arrived I noticed that all four have CW threaded shafts. Is this a problem? Should I return them and get two CW and two CCW?

Also when I turn the motor housings they rotate kind of bumpy. I assume this is normal due to the magnets interacting with the coils. Is this normal or should they rotate smoothly?
Click to expand...

I agree this shouldn't be an issue. It just means you need to tighten the nylock nuts tight. My friend has 2300kv motors, all CW. It came prebuilt and pretuned from a quality California shop. Also, the jumpy rotation is normal for new motors, it is indeed the magnets.
 

Av8Chuck

Av8Chuck

Member
The Steppyness is called cogging, it's normal, they are smooth when energized.

In the old days, about four years ago, it was rare that you would have counter rotating shafts so there were a lot of crashes caused by props flying off in flight. Just make sure the retaining nut is tight before every flight.

If your quad just carries a GoPro, for example, you don't need to worry about this. If you were building a drone to carry an expensive camera and gimbal then it might be an issue. But then again if you were doing that you shouldn't buy cheap Chinese motors of Amazon.
 

M

moonpie57108

Member
I have been on both sides of the fence. I started off thinking I needed CW/CCW to prevent random problems. You will just end up spending extra money and if you need a replacement nut, CCW can be hard to find and if buying from a hobby shop by the nut or pack of 4, terribly expensive. I still run some CW/CCW, but my newest strongest motors are all CW and no trouble on punch out.

The money you will spend on two left hand prop adapters, you can probably buy 100-200 nylock nuts and if they start feeling loose, toss em. And in general, go snug with a nut driver. If you use a wrench or socket pay attention, you can shear off the prop adapter which is made of aluminum. Personally, I use a 1/4" ratchet.
 

Av8Chuck

Av8Chuck

Member
When moving up the food chain with payload and expense, you generally move down in KV and up in prop size, 15", 18" or bigger and most of those props attach directly to the bell housing or a quick release which is CW/CCW.
 


Av8Chuck

Av8Chuck

Member
I don't think he'll win races with 935KV motors. 28" props are ceiling fans. 18" props are just what it takes to lift 36 pounds AUW for 30+ minutes...
 

F

filthy13

Member
Really just want to back up what everyone else has already said ..... doesn't really matter (especially for tiny motors that will likely be spinning 8-10" props). Just be sure and always check hardware before every flight and props should be balanced of course to minimize vibes and chances of loosening everything.

But @Av8Chuck - Lifting 36 lbs for 30 minutes on 18's? I'm only lifting 28lbs most days on 18's and only getting 11-14 mins depending on wind and flying style. I'm doing it wrong obviously! Of course the U7 420 isn't known for being the most efficient :)
 


Av8Chuck

Av8Chuck

Member
filthy13 said:
Really just want to back up what everyone else has already said ..... doesn't really matter (especially for tiny motors that will likely be spinning 8-10" props). Just be sure and always check hardware before every flight and props should be balanced of course to minimize vibes and chances of loosening everything.

But @Av8Chuck - Lifting 36 lbs for 30 minutes on 18's? I'm only lifting 28lbs most days on 18's and only getting 11-14 mins depending on wind and flying style. I'm doing it wrong obviously! Of course the U7 420 isn't known for being the most efficient :)
Click to expand...

It's all a trade off right? Just depends on how much of the AUW is battery. I'm using 435KV KDE motors. We did test a Hex with U7's and it was pretty much as you describe.
 

You must log in or register to reply here.
Top