The CyberQuad

[Cyberdactyl]

Those are HQ 0645. But actually I didn't crash. It plowed through and took a souvenir. I did have a crash yesterday. I hit some thin dead branches with no leaves. That's the thing with these lower res cams, stuff the size of cocktail straws can't be seen until it's too late, even if you're going 15mph. I've found if you hit something small and you're moving fast, and your trajectory is free and clear after the impact, you usually are ok. What happens to me occasionally is you get knocked off your line into thicker obstruction and get tangled up. The trick is, like any multirotor, once you know it's "over", you cut power, and 50% of the time you keep your props if you're low enough to the ground.

 

[zenguerilla]

nice, its in its camo atire,, hiding for that special shot..

I wouldn't notice a hovering quad cloaked in leaf and stem attire...

 

[Cyberdactyl]

Another odd disconnect I experience when going through leaves when the mini is a good distance away is the delay. Many times I clearly see the shutter and shake through the goggles as it powers through some small twigs and leaves, yet it will have completely cleared the obstruction before that brrrraaap sound reaches me.

 

[Cyberdactyl]

Ok, just to report in. I had my first failure of a RCTimer 2208/8 2600KV. Had one start twitching at idle speeds. Took it apart and nothing jumps out, so it must be a hidden winding failure. Got about 25-30 hours out of it. Still have three running strong. Just bought 2 more.

So. . . I am still impressed. They are amazing little mini quad brutes. A bit heavy at 38g but will push in access of 300W at 2600KV with 0645s on 4S. As long as I get a bit more life out of the other three, I'll still say they are a steal at under $9. . . 10.40 after shipping.

 

[zenguerilla]

It's probably just a wire break or you just took a pic after breaking a zip tie to fool us. Right? I mean what does that pic prove...?

Just kidding. I would seriously like to see solder tabs under the windings so fresh wire could be easily replaced. One good thing is that the parts are interchangeable, so damage a 'can' on one of the others and you'll have a replacement. The 'cans' actually look the same for whole motor line, from what I have seen comparing 1450's and 2600's, just the windings are different.

I would say, though, that it is probably between wire-to-winding and wire end, and not actually in the windings themselves. It may also be worth considering the 1800Kv at some point, as that might work for the 4S and 6045's. Besides, have enough interchangeable parts like these and you may end up rewrapping your windings. 1900-2000Kv would probably be pretty nice on these.

 

[BanditJacksRC]

They are amazing little mini quad brutes. A bit heavy at 38g but will push in access of 300W at 2600KV with 0645s on 4S. As long as I get a bit more life out of the other three, I'll still say they are a steal at under $9. . . 10.40 after shipping.

Yeah they look like great motors for the price, but I am always hesitant to buy motors that have a prop adapter. I'd figure I would bend the shaft after the first hard run.

I had a suppo I used with fixed wings, and replaced that shaft at least 3 times before it completely died in a lipo fire (from a pretty hard crash)

 

[Cyberdactyl]

Yeah they look like great motors for the price, but I am always hesitant to buy motors that have a prop adapter. I'd figure I would bend the shaft after the first hard run.

They have screw holes in the bell for screw-on adapters. But yea, I use the clamp-style collets. Admittedly, the height of clamp-style collets does put a fairly large moment on the shaft if I were to crash. But that can be greatly minimized by cutting off about 4mm of shaft and having the collet sit flush on the bell which transfers much of the load to the edge of the collet and the bell's top surface during a harsh bending moment.

Just kidding. I would seriously like to see solder tabs under the windings so fresh wire could be easily replaced. One good thing is that the parts are interchangeable, so damage a 'can' on one of the others and you'll have a replacement. The 'cans' actually look the same for whole motor line, from what I have seen comparing 1450's and 2600's, just the windings are different.

Oh, I did the switch-a-roo with another position and got the same result, and also wiggled the leads to see if it was there. It's in the windings and not visually apparent.

It may also be worth considering the 1800Kv at some point, as that might work for the 4S and 6045's. Besides, have enough interchangeable parts like these and you may end up rewrapping your windings. 1900-2000Kv would probably be pretty nice on these.

The RcT 2208/8 2600KV has an advantage over the lower-turn delta winds of the common 2204 2300s, and even more so, the 1800, with the extra 300-800KV capacity. If the KV can be maintained under heavy load, which the RcT 2208/8 certainly makes the effort with 270W on 3S and around 300W with 4S, it will pull incredibly hard with 0645s. And it definitely seems to. Along with being under $9, makes it a bargain brute on a mini.

But wait you ask, what is the catch? Well it pays the price of weighing in at ~16g more per motor over the standard 2300, eats through more battery, and crashes will be more severe.

 

[zenguerilla]

Oh, I did the switch-a-roo with another position and got the same result, and also wiggled the leads to see if it was there. It's in the windings and not visually apparent.

The RcT 2208/8 2600KV has an advantage over the lower-turn delta winds of the common 2204 2300s, and even more so, the 1800, with the extra 300-800KV capacity. If the KV can be maintained under heavy load, which the RcT 2208/8 certainly makes the effort with 270W on 3S and around 300W with 4S, it will pull incredibly hard with 0645s. And it definitely seems to. Along with being under $9, makes it a bargain brute on a mini.

I don't know what you mean by switcharoo, but you may want to double check continuity on the wires and connectors if you haven't.

I would mainly be assuming this, but if the 1800's/4S/6045 achieved the thrust and rpms normally used, then despite theoretical differences of more potential power, you might be bogging the 2600's more than not.

 

[Cyberdactyl]

Switcharoo means I tried the motor on another ESC where the motor that was there works fine and the faulty motor behaved the same. I also put the good motor where the bad motor was and it ran fine. I also jiggled the leads and bullet connections to see if there was any continuity problems in the leads and got nothing different. I'll just salvage the faulty motor for bearings and anything else I might use. If nothing else, I'll take the neodymium magnets out of the bell, they're always fun to mess around with.

The 2600s don't appear to bog down under hard throttle, but they will dip a 3S 1300 45c down to the low voltage setting on anything but a fresh charge if I hold WOT for more than a couple seconds. I don't have that problem with a 4S 1300 45c.

So far, my only real complaint I had with the components on my mini was the AfroSlims were desyncing with 4S. However, once I flashed them with a current (as in June 2014) firmware, I've had no problems since.

 

[zenguerilla]

If I were you I would probably replace the motor too, but check the leads coming off that motor, between the windings and connectors, at some point.

The 2600's may be able to keep up, but if a lower Kv would be able to match the rpms for the same prop, needed for the required thrust, then it will usually do so with more torque and efficiency, at least as theory has it.

I don't know what flight board you are using, but if it has OneShot capable, the Afros and latest SimonK are supposed to be ready, which could help. You can use RapidFlash to configure, if you don't already use that.

I would still say if they had a 2208/10 or one wrap could be easily removed from the 1800's and I was already comfortably rewrapping them, I would probably give it a try.

As for an upgrade, Cobra 2204's would probably fit the bill nicely.

But I am glad these motors are around as they have performed and held up well for me as well. And the range of application is nice too. I look at them as kind of like vintage american muscle at an affordable price. Where as the others are more like nuespeed, a bit more advanced, compact, etc. They are right on the verge of being a bit too bulky, but they will do fine for the time being.

 

[Cyberdactyl]

If I were you I would probably replace the motor too, but check the leads coming off that motor, between the windings and connectors, at some point.

Not sure how to say it any differently. . . I have done that.

The 2600's may be able to keep up, but if a lower Kv would be able to match the rpms for the same prop, needed for the required thrust, then it will usually do so with more torque and efficiency, at least as theory has it. [/I]

What is unique about the 2600's, is just that. . . 2600kv and be able sustain upper 200s in wattage. If they were 1800 or even 2300, I wouldn't have the interest. But they simply crank 0645s on 3S and are spectacular on 4S, all for under $9. But again, they ARE heavy compared to the array of 2204 or 2206 choices.

I strongly recommend them if those variables fit your needs.

 

[zenguerilla]

Not sure how to say it any differently. . . I have done that.

What is unique about the 2600's, is just that. . . 2600kv and be able sustain upper 200s in wattage. If they were 1800 or even 2300, I wouldn't have the interest. But they simply crank 0645s on 3S and are spectacular on 4S, all for under $9. But again, they ARE heavy compared to the array of 2204 or 2206 choices.

I strongly recommend them if those variables fit your needs.

It's no concern of mine, but when you say you switched motors to that lead, from you ESC and harness, and then put the bad motor on another lead, of your ESC and harness, you're not saying you checked the continuity from where the motor leads connect to the windings and terminate in the bullet connectors.

From what I understand, higher Kv motors do not just cover a higher RPM. Kv ratings will not only imply a torque ratio but and efficiency sweet spot. I do not know, but believe this sweet spot will also relate to the voltage that is applied. As a guess, 2600Kv on 4S is like 3500Kv on 3S, and 1800Kv on 4S is like 2400Kv on 3S, and does not just include RPM's but, again, would also move the efficient sweet spot accordingly.

On the weight, weight is weight, but in the case of Cobra 2204's for example, the weight increase from 24g to 38g, 14g x 4 = 56g, which is around, probably 10% of total weight increase for a not-unusually-heavy mini quad, which I would say would be better suited to 7"+ props, given the availability and quality of Cobra 2204 and like motors.

From what I also understand, one thing among others that gives the Cobras and like motors direct injection, variable cam and turbo boost power is the smaller wire diameter windings, which result in a tighter, more compact and powerful wrap. But, that is something I really only referential and not really working knowledge of or beyond.

 

[Cyberdactyl]

Here's a video Bruce from rcmodelreviews put together on the Sunnysky X2207S 2700KV. . . very similar to the 2600KV 2208's I run and are virtually the same weight. As I've said, the catch is, you have to decide if want to have the extra mass onboard. Also, you'll have to decide if the Sunnysky quality and ~$18 price point is worth it over RcTimer's $9. I say &%$# yes, but that's just my personal anecdotal opinion.

In any case, both these motors will pull extremely hard on 4S spinning 0645s.

 

[Ocean]

Here's a video Bruce from rcmodelreviews put together on the Sunnysky X2207S 2700KV. . . very similar to the 2600KV 2208's I run and are virtually the same weight. As I've said, the catch is, you have to decide if want to have the extra mass onboard. Also, you'll have to decide if the Sunnysky quality and ~$18 price point is worth it over RcTimer's $9. I say &%$# yes, but that's just my personal anecdotal opinion.

In any case, both these motors will pull extremely hard on 4S spinning 0645s.

I believe Bruce was talking about the 2100kv versions.

I have them and run them on 4s 2207, they don't get that warm and its works well for FFF and LOS acro.

My friend however just got the 2600kv 2208, we hope to compare them.

 

[zenguerilla]

Here's a video Bruce from rcmodelreviews put together on the Sunnysky X2207S 2700KV. . . very similar to the 2600KV 2208's I run and are virtually the same weight. As I've said, the catch is, you have to decide if want to have the extra mass onboard. Also, you'll have to decide if the Sunnysky quality and ~$18 price point is worth it over RcTimer's $9. I say &%$# yes, but that's just my personal anecdotal opinion.

In any case, both these motors will pull extremely hard on 4S spinning 0645s.

Definitely lots of power, but I'm not sure those were not the 2100Kv as they are listed at Banggood with 350watts, where as, oddly, the 2700Kv are listed with 305watts, which might seem to indicate a more involved variation than just more or less winding wraps, and/or possibly some mistaken or inaccurate spec ratings.

Another interesting note, in either case, is that in similar 4S thrust tests, 1960Kv Cobra 2204's pulled between 931-992g or more at 19-20+Amps, vs. around 1000g @ 27+Amps for the SS2207, which are also listed @ 34g in weight per motor.

Part of what is interesting to me is that with the more generic 1100-2600Kv line of motors, the Kv appears to be only changed by the variation of winding wrap numbers, with all the other components being the same.

edit: oops, double info post. I often walk away from a post or reply to do other things as I am typing it up. If I were more intently interested I would probably get one of each of the motors and compare some kind static thrust tests per Amp/Watt for each and somehow coordinating with prop variation. I think the 1800's may be more interesting than they may first appear or this time, which are the only ones I do not have at this point. I started with 1450's on 8045's, then 2600's on 50-60-and 7045's, and picked up a couple of 1100's for possible use in an asymmetrical prop application, (smaller or larger props to front or rear).

 

[Cyberdactyl]

Ahh, you're right, Bruce probably is using the 2100's, since he specifically names 2100KV Sunnyskys in a video a few days later, and I doubt he would have purchased both flavors.

 

[Cyberdactyl]

From what I also understand, one thing among others that gives the Cobras and like motors direct injection, variable cam and turbo boost power is the smaller wire diameter windings, which result in a tighter, more compact and powerful wrap. But, that is something I really only referential and not really working knowledge of or beyond.

For the most part, it comes down to the simple specs. More turns on the stator gives more torque but lower rpm. As you said, the RcTimer has several motor models that are identical, except for the wind count, so the result is clear. And it is also clear what the can/bell size is having on the performance. Along with all the other published variables, you can get extremely close in predicting the performance of most any motor.

However, one spec that is basically never addressed is where on the stator's radius is the wrap specifically? It's hard to know how exactly the cross-sectional field shape in the z-axis is sweeping across the magnets. That seems to be a secret that is held close.

 

[zenguerilla]

For the most part, it comes down to the simple specs. More turns on the stator gives more torque but lower rpm. As you said, the RcTimer has several motor models that are identical, except for the wind count, so the result is clear. And it is also clear what the can/bell size is having on the performance. Along with all the other published variables, you can get extremely close in predicting the performance of most any motor.

However, one spec that is basically never addressed is where on the stator's radius is the wrap specifically? It's hard to know how exactly the cross-sectional field shape in the z-axis is sweeping across the magnets. That seems to be a secret that is held close.

Nope, I'm pretty sure wire diameter is as primarily significant as number of wraps regarding Kv and more. Every source I've skimmed across also says smaller wire diameter produces a tighter wrap resulting in more power and efficiency. The RCT, etc. 2208's we're talking about appear to only vary the number of winding wraps and leave the wire diameter, etc. the same.

 

[Cyberdactyl]

Nope, I'm pretty sure wire diameter is as primarily significant as number of wraps regarding Kv and more. Every source I've skimmed across also says smaller wire diameter produces a tighter wrap resulting in more power and efficiency. The RCT, etc. 2208's we're talking about appear to only vary the number of winding wraps and leave the wire diameter, etc. the same.

As I said, that is all part of the specs. The 'copper fill' spec you're referring to is determined by a few variables, but primarily by the wire gauge, which is determined by the amperage you plan to push through the wire. Having a "tighter wrap" can actually be detrimental to the motor, as too tight a wrap can stress the wire and the insulation, especially under high current and heat conditions. On stators with armatures with a square or rectangular cross section (somewhat sharp edges), a wrap tension more than 600g on a 28g magnet wire is asking for trouble.

But again. . . this is all part of the motor's specification and design tolerances. What is not part of specs as far as I have found, is the center of mass of the wrap from the axis of rotation and the resulting field cross section.

What is separating kick-around motors like the Rctimers, the Cobras, the Sunnyskys, etc from motors like the high-end T-Motors is. . . . quality and fit, from using high N-rated neodymium magnets to higher end bearings to excellent magnet wire. As I alluded, there may be a couple trade secrets in structure, but that difference is going to be minimal.

But coming back to my original suggestion to anyone wanting power for a dirt cheap price, and are willing to sacrifice some efficiency, is to simply purchase a stout (somewhat tall) high kv motor like the 2208 2600kv RCT or, if you insist on the comfort and reassurance of spending more money, the Sunnysky 2207 2700kv.

 

[Cyberdactyl]

Here's an interesting video, not so much for the flying, my flying is average, but the loss of a motor. If you look at the ground around the crash site you'll see it's very clear and open. I searched for a radius of a good hundred feet or more and was still unable to find one of the motors. Anyone had this happen? I'm thinking the mini could have spun and thrown the motor up in the tree. . .