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View Full Version : A Great, Cheap, Brushless Outrunner...


I_Love_My_ABC
10-23-2005, 01:48 AM
I've finally taken the plunge and gone brushless on the Slow Stick. The main question I've been asking myself ever since is WHY THE HELL DIDN'T I DO IT SOONER!!!

I was becoming increasingly under-welmed with the flight performance of the GWS speed 370 D-geared setup on the SS in moderate wind and when I had a look on Ebay I found an inexpensive brushless outrunner and 18 amp ESC for sale for less than $60.00AU

I thought what the hell, even if it's not that brilliant it's only $60.00 and I can use the brushless ESC on another motor down the track anyway.
The links are here if anybody is interested...

http://cgi.ebay.com.au/Shuttle-Outrunner-Brushless-Motor_W0QQitemZ5982574915QQcategoryZ2563QQtcZphoto QQcmdZViewItem
http://cgi.ebay.com.au/18A-Brushless-Electronic-Speed-Controller_W0QQitemZ5983728941QQcategoryZ2563QQtcZ photoQQcmdZViewItem

I have bought items from this seller before and I found his service to be outstanding with super fast next day delivery. I see that he will also ship internationally for $10.00AU (Just in case anybody was wondering, no I'm not him and I don't work for him either!!)

The package arrived the next day so I immediately got to work on installing it. I soldered the ESC and the motor wires together and removed the old brushed 370 setup and IPS300 ESC and put them away for a rainy day.

The motor came with a blank GWS gearbox housing and all the nuts, bolts, screws and hardware needed to mount it to either a balsa/plywood firewall or onto any standard GWS style 10x10mm stick mount.

I did have to drill a couple of holes in the plastic to mount the aluminium firewall bracket securely to the front of the gearbox housing. This done I slid the housing over the 10x10mm stick and drilled a 1mm hole for a retaining screw. I wound the excess ESC and motor wires around the stick a few times and retained the ESC with two rubber bands.

http://www.rchobbyhub.com/modules/gallery/albums/album40/Plane_012.sized.jpg

http://www.rchobbyhub.com/modules/gallery/albums/album40/Plane_013.sized.jpg

For the test flight I was using 1 x 900Mah 6 cell 7.4volt NiMh, 2 x 7 cell 8.4volt NiMh ABC packs and I had an 1800Mah 2S 7.4volt LiPo pack in reserve from my Art-Tech Cessna 182. I loaded up one of the 7 cell 8.4volt packs and proceeded to do the pre-flight tests.

I couldn't believe that the motor spun up the very first time I tried it. Usually it takes 10 minutes or so to figure out why it's not working and what I've done wrong but luckily this time I must have fluked it!!

It was evident right away that I had heaps more power than the stock setup!! :D :D as the motor test caused the plane to lift off the ground almost vertically. I immediately cut the power and it landed softly on it's gear again. I just taxied around a bit to get used to it on about 1/4 throttle. This amazed me because the grass at the field I fly in is not super short and to taxi with the stock setup usually takes at least 3/4 throttle.

I brought it around into the wind and opened up the throttle. It again lifted off in about 2 feet and climbed with authority to a height of 100 feet where I did some turns and mild aerobatics. I needed less than 1/4 throttle to keep it up in the air in level flight. There were approximately 8 mph winds.

When I opened up the throttle it took off like a rocket. Inside and outside loops from level flight, approximatly 50 degree climb-outs, rolls, chandelles, tail-slides and so on. The immedate difference I noticed, apart from the huge increase in power, was how quiet it was!! The only noise I could really hear came from the 9 x 47 prop and the servos and that was only when the plane was flying low and close to me.

Two battery packs later I tried the 6 cell 7.4volt NiMh and that was only slightly less powerful in flight. I decided to give the 2S LiPo a go and I have to say I was a bit disappointed with the performance!! It was probably on par with the 7 cell NiMh packs and being so light the plane seemed much more prone to wind.

The only real advantage I could see was about double the flight time (Approximately 15 minutes with NiMh, 30 minutes with the 2S LiPo) but the plane seemed to fly a lot better and much mor stable in wind with the NiMh packs.

The seller claims that this motor will pull a Slow Stick vertical and hover with 3S LiPo's and from what I've seen already I have no reason to doubt him!! I certainly found the motor to be great value for money and a nice little performer. A great buy for the budget minded flyer with blistering speed and whisper-quiet clean raw electric power...

Cheers!!

ForestCam
10-23-2005, 02:15 AM
I bought the same thing and found out it was way under powered for my formosa so I went with one of these
http://www.gwsexpert.com/product_info.php?cPath=104_105&products_id=909

but I'm still using the ebay ESC. :D

Oh and a little secret, if you bend the motor shaft I found out a GWS gear shaft is a direct replacement.:D

Twmaster
10-23-2005, 02:22 AM
I bought the same thing and found out it was way under powered for my formosa so I went with one of these
http://www.gwsexpert.com/product_info.php?cPath=104_105&products_id=909

but I'm still using the ebay ESC. :D

Oh and a little secret, if you bend the motor shaft I found out a GWS gear shaft is a direct replacement.:D

Ooooh. good tip Forest! I have a couple of those motors. Thanks!

bsoder
10-23-2005, 03:06 AM
That looks like a BP-21.

Take a look here - http://www.aero-nuts.com/index.php?cPath=42_43

They offer a couple different setups - a BP-21 + 18A ESC, for $40 shipped, and a BM2410-09Y + 30A ESC for $45, also including shipping. I have one of each. Great deals, the guy is very good to work with. Have to email him directly to get the free shipping, he will also throw other small items in (ie extra shafts) the same free-ship box.

I have my BP-21 on my 52" Zagnutz right now, using an 8x4e APC prop. My 09Y I use on my slow stick variants including my AP plane, on an 11x4.7 APC SF prop.

Great motors, and CHEAP.

I_Love_My_ABC
10-23-2005, 04:05 AM
I bought the same thing and found out it was way under powered for my formosa so I went with one of these
http://www.gwsexpert.com/product_info.php?cPath=104_105&products_id=909

but I'm still using the ebay ESC. :D

Oh and a little secret, if you bend the motor shaft I found out a GWS gear shaft is a direct replacement.:D

Nice tip on the shaft replacement, I'm bound to bend one sooner or later!! It's a shame you found the motor underpowered... is a Formosa a light plane too?? I don't know what the Slow Stick weighs in at but it's light enough to really get blown around in 10 mph winds.

I think this motor was probably only designed for real lightweight park flyer foamies. Over here in Sydney Australia, at my LHS at least, we usually pay that much for a 10 amp brushless ESC alone so it really was a win, win for me!!

As far as the motor goes, the seller told me it was identical to the BP-21, and probably even made in the same factory!! It seems to work well, for how long I don't exactly know. I've heard somewhere that you get what you pay for... I guess that even if it dies I've still got the ESC and if both of them burst into flames I'm not exactly going to cry about $60.00 for a new outrunner & ESC anyway.

Good luck with it all :p :p :p

qban_flyer
10-23-2005, 04:36 AM
I've finally taken the plunge and gone brushless on the Slow Stick. The main question I've been asking myself ever since is WHY THE HELL DIDN'T I DO IT SOONER!!!

I was becoming increasingly under-welmed with the flight performance of the GWS speed 370 D-geared setup on the SS in moderate wind and when I had a look on Ebay I found an inexpensive brushless outrunner and 18 amp ESC for sale for less than $60.00AU

I thought what the hell, even if it's not that brilliant it's only $60.00 and I can use the brushless ESC on another motor down the track anyway.

I have bought items from this seller before and I found his service to be outstanding with super fast next day delivery. I see that he will also ship internationally for $10.00AU (Just in case anybody was wondering, no I'm not him and I don't work for him either!!)

The package arrived the next day so I immediately got to work on installing it. I soldered the ESC and the motor wires together and removed the old brushed 370 setup and IPS300 ESC and put them away for a rainy day.

The motor came with a blank GWS gearbox housing and all the nuts, bolts, screws and hardware needed to mount it to either a balsa/plywood firewall or onto any standard GWS style 10x10mm stick mount.

I did have to drill a couple of holes in the plastic to mount the aluminium firewall bracket securely to the front of the gearbox housing. This done I slid the housing over the 10x10mm stick and drilled a 1mm hole for a retaining screw. I wound the excess ESC and motor wires around the stick a few times and retained the ESC with two rubber bands.

For the test flight I was using 1 x 900Mah 6 cell 7.4volt NiMh, 2 x 7 cell 8.4volt NiMh ABC packs and I had an 1800Mah 2S 7.4volt LiPo pack in reserve from my Art-Tech Cessna 182. I loaded up one of the 7 cell 8.4volt packs and proceeded to do the pre-flight tests.

I couldn't believe that the motor spun up the very first time I tried it. Usually it takes 10 minutes or so to figure out why it's not working and what I've done wrong but luckily this time I must have fluked it!!

It was evident right away that I had heaps more power than the stock setup!! :D :D as the motor test caused the plane to lift off the ground almost vertically. I immediately cut the power and it landed softly on it's gear again. I just taxied around a bit to get used to it on about 1/4 throttle. This amazed me because the grass at the field I fly in is not super short and to taxi with the stock setup usually takes at least 3/4 throttle.

I brought it around into the wind and opened up the throttle. It again lifted off in about 2 feet and climbed with authority to a height of 100 feet where I did some turns and mild aerobatics. I needed less than 1/4 throttle to keep it up in the air in level flight. There were approximately 8 mph winds.

When I opened up the throttle it took off like a rocket. Inside and outside loops from level flight, approximatly 50 degree climb-outs, rolls, chandelles, tail-slides and so on. The immedate difference I noticed, apart from the huge increase in power, was how quiet it was!! The only noise I could really hear came from the 9 x 47 prop and the servos and that was only when the plane was flying low and close to me.

Two battery packs later I tried the 6 cell 7.4volt NiMh and that was only slightly less powerful in flight. I decided to give the 2S LiPo a go and I have to say I was a bit disappointed with the performance!! It was probably on par with the 7 cell NiMh packs and being so light the plane seemed much more prone to wind.

The only real advantage I could see was about double the flight time (Approximately 15 minutes with NiMh, 30 minutes with the 2S LiPo) but the plane seemed to fly a lot better and much mor stable in wind with the NiMh packs.

The seller claims that this motor will pull a Slow Stick vertical and hover with 3S LiPo's and from what I've seen already I have no reason to doubt him!! I certainly found the motor to be great value for money and a nice little performer. A great buy for the budget minded flyer with blistering speed and whisper-quiet clean raw electric power...

Cheers!!
I did the same thing while taking a different path in Out Running my Slow Stick.

Hobby Lobby International has their Esskay 400XT (A.K.A. Aurora) motors on sale at $29.90. Bought me a Great Planes SS-12 B/L ESC for $34.99 and an E-Flite EFLM-1915 stick mount adapter for their outrunners ($4.99).

For a total investment of $69.88 and using three cell Li-Pos I already had, I got me 19 oz. of thrust on the nose of my Slow Stick while sucking less than 9 amps (WOT) from the batteries.

And yes, you are correct, there is nothing like the "sound of silence" (SOS) from these outrunners, all I hear is the propeller noise!

Check post #34 on the thread linked below for a detailed description and pictures of my set up. Hobby Lobby has the 400XTs on sale until the 28th, G/P SS-12 B/L ESCs sell for that price every day of the week. And if I may so myself, the Slow Stick with 400XT set up looks rather elegant (for a Slow Stick, that is).

http://www.wattflyer.com/forums/showthread.php?p=17456#post17456

I_Love_My_ABC
10-23-2005, 05:53 AM
Nice One!! They really do look good don't they those motors... hey, I did notice that you have a strip of velcro just behind the motor, is that where you mount the LiPo??

I had a lot of trouble running LiPo's and trying to get the CG right again. My NiMh's mount under the battery bay just behind the LG bracket and I put the 2S 1800Mah LiPo in the same spot in an attempt to protect it a bit in the event of a crash, but in hindsight mounting it up behind the motor would probably offer as much protection as anywhere else I assume.

Eventually I had to add some lead sinkers near the nose to balance it out again but that kind of defeats the purpose of running LiPo's and cancels out the weight savings doesn't it!! I'll try to mount it up there and see if that makes a difference.

Cheers!!

:eek: :eek: :eek:

bsoder
10-23-2005, 08:24 AM
I have my batts mounted right behind the motor as well. plus, that frees up COG for a camera. :)

qban_flyer
10-23-2005, 06:35 PM
Nice One!! They really do look good don't they those motors... hey, I did notice that you have a strip of velcro just behind the motor, is that where you mount the LiPo??

I had a lot of trouble running LiPo's and trying to get the CG right again. My NiMh's mount under the battery bay just behind the LG bracket and I put the 2S 1800Mah LiPo in the same spot in an attempt to protect it a bit in the event of a crash, but in hindsight mounting it up behind the motor would probably offer as much protection as anywhere else I assume.

Eventually I had to add some lead sinkers near the nose to balance it out again but that kind of defeats the purpose of running LiPo's and cancels out the weight savings doesn't it!! I'll try to mount it up there and see if that makes a difference.

Cheers!!

:eek: :eek: :eek:

Right on. That's where the Li-Po pack goes, I have Velcro on the bottom as well in case the pack needs to go further forward (as when I fly with a two cell pack). About 1/2 inch behind the motor is where the three cell Kokam & Great Planes 640s go, the Thunder Powers go a bit further back than that.

Since I use Kokam, Great planes 640 mAh packs as well as T/P 900s I need to have an adjustable method of mounting the packs to have the CG where it belongs. I also make sure to have three small rubber bands (wrapped from side to side over the battery and under the boom) to prevent the packs from falling off when inverted or looping!

I'll take a picture of the battery on the plane and post it here so that you'll get an idea of how I use the rubber bands.

qban_flyer
10-23-2005, 06:36 PM
I have my batts mounted right behind the motor as well. plus, that frees up COG for a camera. :)

Same here. Isn't it amazing how different minds think so much alike?

qban_flyer
10-23-2005, 06:55 PM
Here are the "rubber banded" battery pack photos.

tim hooper
10-23-2005, 09:16 PM
I bought one of these motor/esc combos too.

It's found a home in a little Minibat - a 36", 15oz very lively aerobat, where it seems more than happy! a 3S1P 1500mah gives flights of (timed) 14 minutes, which equates to an average current draw of around 6A.

My example doesn't seem particularly well balanced though, and causes a resonance in the airframe at full chat. No matter - it's cheap, it's cheerful and an absolute bargain for thirty quid. :D

tim

I_Love_My_ABC
10-23-2005, 09:23 PM
Here are the "rubber banded" battery pack photos. Just as a matter of interest, how long in flight time do you get with the 640mah LiPo's?? With an 1800Mah 2S pack I get somewhere in the vicinity of 30 minutes. (And sometimes up to 35-40 with some good throttle management) Whilst the 900Mah 7 cell NiMh ABC packs give me around 15-20 minutes.

I_Love_My_ABC
10-23-2005, 09:25 PM
I bought one of these motor/esc combos too.

It's found a home in a little Minibat - a 36", 15oz very lively aerobat, where it seems more than happy! a 3S1P 1500mah gives flights of (timed) 14 minutes, which equates to an average current draw of around 6A.

My example doesn't seem particularly well balanced though, and causes a resonance in the airframe at full chat. No matter - it's cheap, it's cheerful and an absolute bargain for thirty quid. :D

tim
Nice one!! I had a bit of a vibration in mine too but after I balanced the prop it went away. Give it a try!! Good Luck...

qban_flyer
10-23-2005, 11:32 PM
Just as a matter of interest, how long in flight time do you get with the 640mah LiPo's?? With an 1800Mah 2S pack I get somewhere in the vicinity of 30 minutes. (And sometimes up to 35-40 with some good throttle management) Whilst the 900Mah 7 cell NiMh ABC packs give me around 15-20 minutes.

With this set up I need to manage the throttle, otherwise I may rip the wings off my Slow Stick. So, the times given below are under throttle management.

With the three cell 640 packs I get just over 15 minute flights before the motor cuts off. With the three cell T/P 900 packs I get a bit over 24 minutes. This motor/ESC/battery combination seem to be rather efficient with the Slow Stick.

If I switch to two cell T/P 1320s and an 11X3.8SF APC propeller, I get over 36 minute flights, easily. Though this combination is not as impressive (performance wise) as with three cells, it is more than double the power of the stock motor.