The Hacker A40-14S pulling about 1000 watts on 6S and a 14x6 prop will fly hard 3D for 5 minutes without frying. I weighs 208 g without prop adapter. I would not expect a 166 g motor (prop adapter included) pulling 70 Amps through it with a 15x7 prop to last very long depending on where you fly it.

It might last a little while running where Gus is in January. Bring it to NKC in July and see how it stands up.

 

No need to wait till January, come on over today before it gets too hot.

 

I was jealous when I saw you score that deal on rcg Mike

I've kind of consider a 200 gram motor to top out at about a 4.5 lb plane at around 1200 watts about the top end that's safe, and will be happier on a 4lb plane.

That being said some guys are pushing big juice through the motor you got and I'm curious how they are getting by?

How many bearing does it have, how big are they? Etc? The short fat stator probably cools well?

The other thing is most are using on the 48 and new 52 inch ef planes, they aren't that heavy so I'm thinking they probably just aren't using them that hard over all and getting by with it?

 

I think plane weight is important in this type of discussion as that greatly affects your average watts pulled

 

If you go too light on the motor, you waste a lot of energy in heat. I don't think "how light of a motor won't fry?" is the right question.
I think 200g is the lightest that is reasonably efficient.

 

This is why I am going to try the Motrolfly 3615 570 KV Zam recommends. See his comments halfway down this page:

http://www.theprofilebrotherhood.com/forum/viewtopic.php?f=110&t=37823&start=40

 

That is one of their new motors. They are getting smart! That looks to be a single stater design. It seems to be a little thinner than the 3615 but is a little larger diameter. That means more of the windings are exposed to the air and the can looks to be open pretty well for good air flow through it. I would not be surprised to see it take the 1000 watts no problem. Especially on a slab flying 3D.

I was always impressed with how hard you could push the Torque series of motors and they take abuse great. Hopefully the same folks had a hand in designing these motors. They are going in the right direction, in my opinion, with a larger diameter stator. My gut says this could really rock a 40 sized profile! But, that all depends on the quality of the components used to make it. If it is to the same standards as the Torque motors I will have to try one out. Looking forward to your test report! I would not be afraid to run it at over 1000 watts.

I think grams per watts is different depending on the stator design. Large diameter, thinner stator (how long the motor is) is going to be able to handle more power than a motor of equal weight that is a smaller diameter and longer..it is harder to get the heat out as fast when just using air..

 

If you go too light on the motor, you waste a lot of energy in heat. I don't think "how light of a motor won't fry?" is the right question.
I think 200g is the lightest that is reasonably efficient.

:rolleye:

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

I am guessing a Chairlift motor let out the magic black smoke. Gotta keep that shit in there.

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

I am guessing a Chairlift motor let out the magic black smoke. Gotta keep that shit in there.

Though 99% of the time I agree with you that we gotta keep the smoke in I know of one motor on a machine at work that disagrees with us. Twice now in the last year it has let out the magic smoke and it still keeps on ticking. First time the chain the motor turned broke and wrapped around it locking it up and let out lots of smoke and just last week I get called out to the line and I hear the motor humming and see smoke a rolling from it. Find the motor starter welded itself shut. Needless to say both times I checked it with my Simpson 260 and still reads good. Fixed the motor stsrter and its running fine now. I see it as two strikes though and don't think it will survive strike three.

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

I am guessing a Chairlift motor let out the magic black smoke. Gotta keep that shit in there.

Though 99% of the time I agree with you that we gotta keep the smoke in I know of one motor on a machine at work that disagrees with us. Twice now in the last year it has let out the magic smoke and it still keeps on ticking. First time the chain the motor turned broke and wrapped around it locking it up and let out lots of smoke and just last week I get called out to the line and I hear the motor humming and see smoke a rolling from it. Find the motor starter welded itself shut. Needless to say both times I checked it with my Simpson 260 and still reads good. Fixed the motor stsrter and its running fine now. I see it as two strikes though and don't think it will survive strike three.

Then it didn't "let the smoke out". It just overheated and was burning the varnish, paint, and old crap off it. You can't burn the windings on a motor up and it still run.

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

I am guessing a Chairlift motor let out the magic black smoke. Gotta keep that shit in there.

Though 99% of the time I agree with you that we gotta keep the smoke in I know of one motor on a machine at work that disagrees with us. Twice now in the last year it has let out the magic smoke and it still keeps on ticking. First time the chain the motor turned broke and wrapped around it locking it up and let out lots of smoke and just last week I get called out to the line and I hear the motor humming and see smoke a rolling from it. Find the motor starter welded itself shut. Needless to say both times I checked it with my Simpson 260 and still reads good. Fixed the motor stsrter and its running fine now. I see it as two strikes though and don't think it will survive strike three.

Then it didn't "let the smoke out". It just overheated and was burning the varnish, paint, and old crap off it. You can't burn the windings on a motor up and it still run.

Yes I agree but if you had seen it rolling smoke you wouldn't think it would run anymore either as the cloud of smoke was filling up the room the machine was in and was thick enough we couldn't see through it.

 

Yea you probably burnt 38 years of dust and crud off the windings

 

Yea you probably burnt 38 years of dust and crud off the windings

Nope I know the difference in the smell of burning dust and burning electrical components.

 

And that smell does not go away.

Oh, and subscribed :tu:

 

What's happening in your pcs Gus? Did a Christmas tree get too hot?

I am guessing a Chairlift motor let out the magic black smoke. Gotta keep that shit in there.

Pump, no lift.

 

So Mike?

 

conclusion reached OP updated with video

 

You put an amp meter on it?

 

No I have not, but I probably should to double check my telemetry. My graupner realtime telemetry which is nothing more than a 4s balance lead into rx port has voice alerts for 2 alarm setpoints and frequency of alerts, So alarm one is set to 3.5VDC per cell of which a stop hovering on deck, and alarm two set to 3.3VDC, of which I land with 15%-18% left in pack.

Seeing that JR is dying I am so pleased with the Graupner radio with all the telemetry options, voice alerts, Mp3 player, bluetooth, and smart flight integrated rx for FB helis, multirotors FC, 3 axis FC and more to come, I only have 1 season on it but not a single hiccup or utghtOH......

Will advise..............

 

watt meter readings added to OP

 

I like your specs for that set up . I don't worry too much about weight on the motor for a 40 size bird . The slabs usually need all the weight they can get in the nose if you like a neutral balance . The mad yak 50 I got from Mo has a motrolfly 4315 , 1lb lipo on the nose and some lead to help out .

 

Mike I need some data on that motor with a 13x6, help a crack out?

 

Mike I need some data on that motor with a 13x6, help a crack out?