eajohnson

My Feedback: (1)

I noticed these the other day and have ordered one (for the price, why not?). I'm curious whether anyone had experience with these motors yet?


New/improved version:
http://www.hobbycity.com/hobbycity/s...idProduct=7710

Old version:
http://www.hobbycity.com/hobbycity/s...idProduct=4188

Seems like they are claiming better magnets, bearings, efficiency/output, 1200W greater max output.

RC_Pattern_Flyer

My Feedback: (1)

It should work, a little heavy but should work if you are extremely careful building your model.

Chuck

tIANci

All these cheap motors will work fine but they are cheap and you get what you pay for. I used quite a few of them and the are fine for sport flying and semi competitive flying. If you want insanse performance then they are not the way to go. They usually cannot hold up well for that sort of demand.

FreeS7yl3r

Hi,
which one have you ordered and could you post info when you test it ? I have the older version,but have no time and props to test it.

Thanks,
Pavel

Anthony-RCU

My Feedback: (2)

About the same weight as an AXI. The old version specs much smaller props and only 6-8 cells the new 8-10 . The old version is also 40g lighter.
Keep us informed on your progress.

wattsup

My Feedback: (1)

Well, this is the first time I've participated in any discussion here on RC Universe. I just could not stand this any longer! I purchased this particular motor & even paid extra to have it shipped < 7 days. My plan was to use it as an inexpensive replacement for my AXI 5330 FAI motor in my practice plane. Upon arrival, I installed it in the practice plane
& hooked up my Medusa Power Analyzer II & proceed to break it in carefully outside the garage at home. Everything was going great up until approx 4 !/2 minutes which at that point the bearings failed, the motor started losing power & then it seized up! I knew it, I should have listened to TIanci earlier in this thread. The hobby operation that markets this motor has totally misrepresented this product in their ad! Also note there are two (2) different prices in their ad. I'm not new to pattern & converted to all electric 3 yrs ago.
My advice, BUYER BEWARE/YOU GET WHAT YOU PAY FOR! Suffice to say, I will do two (2) things in the future: Buy Quality motors & not do business with this company!_ TNWalker

patternflyer1

My Feedback: (11)

4 1/2 minutes on the ground? I'm sure it overheated.
Bummer

ExFokkerFlyer

My Feedback: (4)

Break in? These are not reciprocating engines with rings and such that need to seat... THERE IS NO NEED TO BREAK IN these motors. In fact, aside from a short burst at full power (something I HATE to do) for a few seconds to get a wattmeter reading, there is no need to run these things up on the ground. If you do not have adequate cooling over the motor, and you likely won't be able to do that with an extended static run on the ground anyway, you WILL burn these things up.

You are right, the bearings are the weak link on these cheap motors. I have run a handful of them and can attest that they in fact do have more than enough pattern up through FAI. That's not the issue, longevity is. Most of the motors are okay, but if you are planning on running these things day in day out, replace the bearings right away and be done with it. So what, that makes a $70 motor a $100 motor... big deal.

I would bet, unless you unintentionally misrepresented how you ran this motor up, that you would have burned up an AXI, Dulsky, Hacker etc... running them like that. I don't really care if you buy from that company again or use their motors, but I'd hate to see you burn another motor up thinking you have to break it in. Install it, take a reading and an RPM with a run for 5-15 seconds or so, and go fly. Anything else is unnecessary.

Regards,

Tom M.

wattsup

My Feedback: (1)

Tom, perhaps I chose the wrong words. "Break in" period was really the total time spent taking a reading with the Medusa, checking the throttle curve, setting the low throttle/idle,
etc. Also there was more than adequate ventilation to the motor_ie, no cowl & the air temp was 42 degrees, APC 19x12e prop. But, I will stand by my first response in this thread about this motor. Also, I took a temp reading of the motor with my infrared thermometer which read 85 degrees. I'm not sure but I believe if you advertise that the motor has Japanese bearings surely they've got to be better than most Chinese bearings. For the record, I've run three (3) large AXI motors & 1 Dualsky motor over the last 3 years. The Dualsky lasted 142 flights before it failed (metal fatigue) which come to find out was not uncommon for that motor. My three AXI motors are still going strong with only one of the 5330 F3A motors needing a single bearing change during these 3 years. So, I feel certain I know what I'm doing. Just thought I would "fill in the blanks". For the record, this is more than just about the $79.95 + ship spent on this motor. Some of these overseas manufacturers & retailers need to understand that it can come back to haunt them when they
knowingly design, manufacture & sell GARBAGE! Yes, I realize we (the electric pattern community) are relatively small but, we can & do spend alot of money & can have a direct
impact on their ability to market here in the U.S. Keep in mind, this thread is being read all over the WORLD! Anything else? I really want to pursue this more!_________TNWalker

gfrosty

I have one of these motors in the post to me but am now wondering which speed controller I'll need. Does any one know if the CC 85A HV will be enough for this motor if your running something like an apc 20x15 or 21x13W? Obviously it would only be bursts of current anywhere near 85A but I would quite like to know roughly how much current it will take for those sort of size props.

Once I've got the esc and batteries I'll post my findings but that could well only be in a couple of months.

Cheers
Gordon

wattsup

My Feedback: (1)

gfrosty, you might want to exercise some caution with the larger props_ie, 20x15 & 21x13W. Accordiing to my Medusa, I registered 65 amps with an APC 19x12 before the bearings failed & the motor seized! I've always used the Jeti Spin units but I do know the Castle 85A HV is one fine controller. I jumped in here because I felt you might need some addiional imput. I wish you future success with this particular motor. I really was looking for a cheaper/reliable alternative for my practice plane._________TNWalker

gfrosty

I will very cautiously try those props as this is going to be my first large electric plane. But I will be wanting one that gives me enough speed for windy conditions. Its very much a test setup that i'm doing anyway so we shall see what happens. If a 19x12 is only taking about 65A then I suspect the motor could handle the 20x15. You just don't use full throttle for very long which with that setup you shouldn't have to. Unfortunatly when I bought it no-one had had any experiance with them, or at least they weren't sharing their experiance with others.

Cheers
Gordon

wattsup

My Feedback: (1)

gfrosty, Please let me give you some insight based on trying to run both the 20x15 & 21x13w props on both my AXI 5330 FAI motors. These props overloaded both with amps
of 85+ & infrared temps of 165 degrees + taken directly on the motor not thru the Jeti Spin unit. At this point my plan is to purchase either a Plettenberg 30-10 EVO or the NEU
geared FAI motor & use the AXI 5330 motors as practice motors. I've found the best prop for my two motors is the 20.5x14 APC. Fortunately I'm financially able to purchase any glow motor or electric motor currently available. I feel sorry for the pattern flyer who can only afford a peice of GARBAGE like this. They have been victimized twice, when they bought it & again when they realize it will not do the job as advertised! It's obvious to me that the hobby operation that sells these motors could care less about our best interests.
If you don't believe that, take the time to read their "Return Policy". Talk about jumping thru some hoops! Anyway, I wish you the best.__________________________TNWalker

ExFokkerFlyer

My Feedback: (4)

I'm not sure how you are running these props, but under normal use, they will not burn up the AXI motors. I have done some pretty extensive testing on those motors (plenty of my results have been posted on my site, along with others) with props up to and including 22x12. None of them burned up an AXI and 85+ amps is okay PROVIDED that those readings are ONLY achieved at wide open throttle and only used in bursts if ever. Unless your plane is 12.5 lbs or greater, you should not ever achieve full power under normal pattern flying with the AXI. High winds, low on speed, sure, for a few seconds, but sustained runs at WOT? Shouldn't happen. I don't like the 20x15 or 21x13W props myself, but they didn't tax the motor excessively either. But again, this is with normal use, not long run-ups on the ground/shop/bench.

One thing to keep in mind when taking temps. Motors like the Turnigy that have a shiny, reflective surface will NOT give you an accurate temp reading when shoot the can. An AXI or any motor with a dull surface, or a sticker on the can, will give you a better reading. In any case I found that more useful information can be had by shooting the temp gun into the motor and seeing how hot the windings were. If you had done that with your failed Turnigy, I think you might have a more eye opening result with the temp gun.

Regards,

Tom M

DaveL322

Gordon,

You may already have similar experience from smaller electrics, but, I would caution a couple things -
- don't expect linear increases in amps with increasing prop size and decreasing RPM.
- don't expect amps in air to correlate with amps on the ground.
- don't expect relative amp/RPM differences on one motor to translate directly to other motors.

MOST of the above relationships are close to linear, but only within a range. The "gotchas" happen when you are using props that are stalled or partially stalled on the ground, when the motor is on the edge of it's torque curve (at which point amp draw goes up very quickly), or the lipo is pushed very hard (C ratings mean very little, voltage under load is what really matters).

From my experience, any motor that makes a reasonable amount of power (65 amps is certainly reasonable) on a 19x12E will not be able to handle a 20x15.

Regards,

Dave

gfrosty

Thanks for the advice. I have had a fair bit of experiance with the smaller electrics so already know most of that. Out of interest. How do you know when the props being stalled or about to stall. Presumeably the current will go through the roof or it starts making some awful noise's. They say " Suggested Prop: 22x12 / 24x10" but quite a few people over rate their products. I'll end up getting quite a few different props to see one will best suit me and the motor.

Cheers
Gordon

DaveL322

Gordon,

I don't have a good answer for that!

I do quite a bit of static testing as well as Eagletree logging. Just as examples.....if I see prop/rpm/amps like the following series (static testing)....

19x12/6800/50........20x12/6600/60..........21x12/6400/70...........22x12/5800/85 - I'd guess the 22x12 was too much prop for the motor (more load than available torque) - but it might be ok in the air (for pattern) as the prop might unload considerably.

or

20x10/6800/50........20x11/6600/55..........20x12/6400/60...........20x13/6200/64........20x14/6200/63.......20x15/6300/62 - I'd guess the 20x15 was relatively more stalled on the ground compared to the other props. With electrics, most props have similar RPM but fewer amps in the air......if I see the above trend in static data, I'd not be surprised to see lower RPM and higher amps with the 20x15.

Personally, I find quite a few of the manufacturers recommendations are of little use - either from being overly conservative (ie, amp ratings on Hacker outrunners.....which are very low if any amount of cooling air or partial throttle is used), or being overly aggressive about hyping the product (the lipo brands "race" to claim the highest "C" ratings....which is silliness for pattern.....40C means at most 90 seconds of airtime).

Regards,

Dave

wattsup

My Feedback: (1)

Dave, thanks for jumping in here! I was starting to get weary dealing with some of these folks that were "running around & jumping to conclusions". They have got to be in great physical shape! It's very easy for them to draw their own conclusions after reading into the situation. For the record, both of my AXI 5330 FAI motors are still running GREAT!
Again, thanks! I'm appreciate your explanation & imput. This is really what Gordon needed to hear/read. He certainly did not need to read the part of this thread where I was being taken to task! The new NEU FAI motor is starting to look like the motor to run if your really serious about e pattern. I wish Steve the BEST!___________________TNWalker

gfrosty

Thanks for the examples Dave. Very helpful. I should think you must also notice a considerable loss of thrust when the prop becomes stalled as well as quite a lot of prop noise. I'll start with a 19x13 apc so that I know what current it should be and then work from there.

Cheers
Gordon

matt13

Hello Tom,
I read your Black Magic posts with the "cheap" motor, but I could not see if you said which Turnigy motor you were using.
Was it this one, and are you still flying with it? Matt

wattsup

My Feedback: (1)

Dave, for the sake of clarification, would you please tell us more about your "static testing" you mentioned earlier in the thread. I felt certain I was not the only e flyer who had
done some "static testing" in the past. Also, tell your father Ron I said hello! I last saw him/hung out at the Rough River,KY contests. Regards____________________TNWalker

DaveL322

TN Walker,

My static testing - I did more when I was new to electric before I developed a "feel" for how electric power systems behaved. Basically, my goal with static testing is to get a sense for where the torque "cliff" is on a given motor. I use a whattmeter and a tach, or an Eagletree w/ added RPM sensor and LCD display, and a variety of props, starting with what I know is small. I increase prop size until I find the "cliff" (slight increase in load produces relatively big drop in RPM with large increase in amps). As previously mentioned in this thread, care needs to be taken when static testing to not overheat the motor, ESC, or lipo, and the static numbers do not always correlate to flight data - but they do establish how much power (in terms of amps or watts) a motor can handle. It is worth noting that most APC "E" props unload 5-15% amps in the air, but the glow props (when run on an electric motor) do not seem to unload much at all - maybe 5% amps.

I also do a little bit of static testing to see how different lipos hold voltage under load - easier to do a lot of tests statically than it is to fly many flights (although flying is more fun!).

Rough River?? Wow....that was a long time ago!!

Regards,

Dave

wattsup

My Feedback: (1)

Dave, thanks for your response.You've added credibility to this thread based on your education & experience. In retrospect, based on you explanation of the torque "cliff", I
like many other e flyers have probably experienced this phenomenon, but was only aware that something did not seem or feel right with the drop in RPM & increase in Amps.
I have felt this several times when I would try a different/larger prop, ie_it felt like the plane was losing power. Does that make sense? According to my records of each flight,
I also noticed an increase in the temp reading from the Jeti Spin unit. I'm sure the temp readings from the Spin unit are not that accurate but, some inflight temp reading is better than not having any at all like some of the other ESC's. I'm glad I jumped into this thread because there are times when a discussion like this can provide that tiny bit of info that
can really make a hugh difference. Knowledge is truly power! My problems with the Turnigy motor are a mere inconvenience.________________________________TNWa lker

ExFokkerFlyer

My Feedback: (4)

Matt,

The motor I had in the Black Magic was the older version of the Turnigy. Between my Dad and me we have used three of them. One is still going strong, 40-50 flights. The one originally installed in the Black Magic had it's bearings replaced after 50 flights. After that, it lasted one flight... probably bad bearings again as they were simply what the LHS had laying around as replacements. I tried yet another on the BM and it lasted four flights before I became wary of it's bearings. I put the AXI back on the Black Magic and have a couple of flights on it. That motor has 4-500 flights on it and might have to have it's bearings replaced as well.

Tom M

can773

My Feedback: (1)

For some educational reading,

http://www.rare-earth-magnets.com/ma...saturation.htm

I found that site gave a decent explanation of why the "torque curve" falls off.

The motor manufacturer's (really the designer) should be able to provide the end user an operating point where saturation occurs, but for some reason none of them do....maybe to hide how crappy their motors are LOL