Large custom inrunner BL motor build, parts from Applimotion INC.

[dogon1013]

First, I would like to point out that this is not a beginners project, It requires Lathe and Mill work.


I recently talked with someone at an industrial brushless motor design and manufactureing company (Applimotion Inc.) about purchaseing Stator material to make my own large outrunner brushless motors for use in RC planes or helicopters. Although they did not have any stator material for me they were interested in RC electric flight. They just so happened to have several motors that did not meet design specs for some medical device (A small cut in the insulation of one wire), but might be perfect for a large RC power plant. This is what I am now trying to build.

Applimotion only makes the stator and magnet assembly to be built into some electrical device. So now it is up to me to build a case and shaft for this new motor.

The specs given for this motor are:
OD: 2.2"
ID: 0.97"
Stator Length: 1.1"
Res: 0.12ohm
Ke: 4.7 V/Krpm (this is equivalent to 212 RPM/Volt)
Kt: 6.4 Oz-In/Amp
Number of magnet poles: 8
Number of Stator poles: 12
Max Voltage: 200V
Max Cuurent: 65Amps
Max recommended RPM: 6,000 (I was told that above 6K it will loose efficiency)

cuurently I plan on feeding it 18Volts and pull up to 35 amps for a total of about 630watts.

I am calling this the BFI 5628

[dogon1013]

If you would like to purchase one of these motor kits for your own build drop an E-mail to:

rob@applimotion.com

Be sure to put "Motors for my RC" in the subject line.

He charged me $65 for one set which includes the wound stator and the magnetized magnet tube. They do have a small gash in the insulation of one wire but it can easilly be repaired.

You could use your own magnets but Applimotion has used FEA programs to be sure that it is very efficient with the magnet supplied.

NOTE: he only had about 2 dozen of these reject motors

[dogon1013]

Here is the design I have so far.

It is recommended that you use some "Back Iron" behind the magnets (at least .125" thick). this Back iron will be attached to an 8mm shaft and i plan on using Skate bearings as the bearings.

I will make an aluminum housing. A simple tube with 2 aluminum end-pieces pressed, or bonded in.

I just got back from a local metal supply store and found some suitable aluminum tubing and bar stock for the case. The tube will be the first thing i make. I plan on gluing the stator into this aluminum tube.

Any suggestions are welcomed. I have built outrunners before, but no in-runners.

[plumb]

How much do they weigh? I may be interested in a statorless version... not quite a 2.2 incher, maby 1 1/4 would do.

[dogon1013]

I just finished machining the case...(boy it's nice to have a lathe in the garage).

The weight of the stator and wires is 11.5oz

Plumb,
I don't think anything that Applimotion makes is coreless. Your on your own there. I do remember seeing some build threads about that.

[fly_boy99]

Wow this looks like some motor!!! Heck put this baby in a gearbox and go to the moon!!!

I might have to join you as I just got a lathe!!!

projects projects!!!
fb ;)

[dogon1013]

with a KV of only 212 you might need to gear it up....

The axi 5330/24 has a similar kV (197) and they suggest a 23" or 21" prop direct drive.
http://www.modelmotors.cz/index.php?id=en&nc=produkty_vypis&kategorie=m_neodym_ac&id_rady=axi_53&id_produktu=axi_5330_24&nazev_rady=Series%20AXI%2053%20GOLD%20LINE&hmotnost_rady=(495%20-%20652g)


Lathes are fun, but you might find your self spending more money on tools, than on planes....

[dogon1013]

well after stalling the lathe about 4 or 5 times (during cutoff), i finally got the lathe work done on one end cap. It took alot longer than I expected. (This size stuff really could use a larger, more powerfull lathe)

I will put the lightening holes and mounting threads in manually using a drill press.

[dogon1013]

I finished the lathe work on the other end cap. But since it is new years and all (----Happy New Years---) I can't use my friends drill press, since he is a t a party.

So I rigged up my own drill press on the lathe. I Marked all the holes by hand using 2 rings i etched into the face of the endcap when it was still on the lathe. after marking the holes i mounted it to the lathe and then clamped it in place and drilled and tapped the holes. I just finished on endcap, but will probably call it a night and finish the other endcap tomorrow.

I also cut the shaft to length and lightly filed it so that the bearings would not be too tight.

[dogon1013]

Well i finished the other endcap. I even did a little wet sanding to get it looking nice.

I still need to make the Back Iron and then glue and press it all together. I might actually get it spinning by tomorrow.

I'm pleasantly surprised at how easy it is to make an inrunner compared to the Outrunners. there is not as much precision needed for the inrunners as there are less rotating parts to get perfect.

[dogon1013]

just finished the back-iron. I drilled the hole a little big so i didn't get a press fit but that's what loctite is for.

Tomorrow I'll start glueing everything together.

[fly_boy99]

This lathe is a four chuck lathe and it's pretty much all setup but I know what you mean about buying more and more tools for it.

Looks good... hope she'll hold up for a 23" prop at a 30A load!!!

Where did you find a 8mm shaft? I assume you will use two backplates...

As for the tab you will be using to keep the stator in a single place while the magnet spins the shaft at < 6k rpm right? Maybe you can elaborate here... ;)

with a KV of only 212 you might need to gear it up....

The axi 5330/24 has a similar kV (197) and they suggest a 23" or 21" prop direct drive.
http://www.modelmotors.cz/index.php?id=en&nc=produkty_vypis&kategorie=m_neodym_ac&id_rady=axi_53&id_produktu=axi_5330_24&nazev_rady=Series%20AXI%2053%20GOLD%20LINE&hmotnost_rady=(495%20-%20652g)


Lathes are fun, but you might find your self spending more money on tools, than on planes....

[dogon1013]

The 8mm shaft came from a local surplus store here in Orlando called skycraft surplus.
It was just a generic 8mm shaft, relativelly soft material. I will probably order a stronger shaft for the next one.

No tab to hold the stators on. I'm just gonna loctite the stator to the tube. It should hold fine, there is alot of surface area.

Yes the 2 endplates are identical, they will be pressed into place with a little loctite as well.

I don't think a 23" prop is reasonable. I'll start small, 12" to 14" maybe.

I have a .60 Lancair that this should power well.

[ImaBiggles]

The 8mm shaft came from a local surplus store here in Orlando called skycraft surplus.
It was just a generic 8mm shaft, relativelly soft material. I will probably order a stronger shaft for the next one.

No tab to hold the stators on. I'm just gonna loctite the stator to the tube. It should hold fine, there is alot of surface area.

Yes the 2 endplates are identical, they will be pressed into place with a little loctite as well.

I don't think a 23" prop is reasonable. I'll start small, 12" to 14" maybe.

I have a .60 Lancair that this should power well.


Drill blanks make excellent shafts - look in mcmaster.com and search for drill blanks. A 12" prop on that beast is like putting and EDF on a Airbus. At the above stated KV, you gonna need a BIG prop (or gear it up 6:1)

[dogon1013]

yea, i'm sure your right. I may need to up the voltage. or maybe just gear it up.

[sneu]

[QUOTE=dogon1013]
The specs given for this motor are:
OD: 2.2"
ID: 0.97"
Stator Length: 1.1"
Res: 0.12ohm
Ke: 4.7 V/Krpm (this is equivalent to 212 RPM/Volt)
Kt: 6.4 Oz-In/Amp
Number of magnet poles: 8
Number of Stator poles: 12
Max Voltage: 200V
Max Cuurent: 65Amps
Max recommended RPM: 6,000 (I was told that above 6K it will loose efficiency)/QUOTE]

With a resistance of .120 ohms don't plan on putting much current into that motor. I think that you will end up doing damage to the windings at much over 20-30 amps.

Steve

[dogon1013]

Yea, The resistance is the one thing that is not like the usual RC motors. But the manufacturer claims that the winds can handle up to 65amps, though I am sure that I will have to keep an eye on heat.

[sneu]

Yea, The resistance is the one thing that is not like the usual RC motors. But the manufacturer claims that the winds can handle up to 65amps, though I am sure that I will have to keep an eye on heat.


From what I see I would suggest that the 65 amp rating is for only very short durations. One other item that makes me believe that the useful power rating will be low is the rather small amount of "back iron" in the stator. The noload current may well be a little high too.

Steve

[dogon1013]

I'm gonna buy a better hardened steel shaft before i finish assembly so it will be at least a few days before i get it spinning. I have to believe that the back iron on the Stator is sufficient, since it was FEA'd. There is a requirement for Back iron on the permanent magnets, but not the stator. You'r right, though, it doesn't look like much.

[sneu]

I'm gonna buy a better hardened steel shaft before i finish assembly so it will be at least a few days before i get it spinning. I have to believe that the back iron on the Stator is sufficient, since it was FEA'd. There is a requirement for Back iron on the permanent magnets, but not the stator. You'r right, though, it doesn't look like much.


Trust me FEA does not always give you a good product--Ask Aveox about some of their earlier designs. Some of the best lamination designs have been done with a bit of luck and common sense:)

FYI back iron on the stator is very important to close the fields. As a rule it is a good idea to have the back iron 2-3 times the thickness of the stator tooth.

In any even good luck.

Steve

[dogon1013]

Well 2 to 3 times the stator tooth thickness would be 1 to 1.5inches, which would make this motor WAY too heavy.

[DavidB.]

Steve meant thickness, not length. The thickness would be something around 1/8" or so.

[dogon1013]

well that makes more sense.

I measure the stator thickness at 4mm (fully covered in powder coat) and the back iron is just under 3mm (only half covered in powder coat), so it is close to 1 times the thickness.

[dogon1013]

I just got the new hardened 8mm shaft in today (from MSC) so i should be able to start assembly later today....After I do some flying, the weather is great today.

[dogon1013]

Just finished the assembly. Weight is 21 oz. It has very smooth cogging.

I'll give the locktite time to cure. I'll try to make it spin tomorrow evening.

[fly_boy99]

Make sure to do a noload current measurement with a 2S lipo then you can do a variety test of props say 3-4 at a certain voltage and use MUMTATS to see how close the Kv really is.

[dogon1013]

MUMTATS ???? what's that.

Unfortunately all my Lipo's are at least 3S, but a friend of mine might have a 2s lipo that I can use.

[fly_boy99]

Do a search... Vintage1 made an excel calc sheet which derives most critical motor data points from sample prop measurements.

Do a search you'll find it fast and it's pretty accurate. The reason I say use a 2S to start with is that on a brand new motor the last thing you want is to kill it on a noload test. So if something is not right you aren't pushing it to the extreme right away.

Steve makes a good point about the resistence... if you burst this sucker then I'd definately invest in a IR temp gun to check it often.

[dogon1013]

found MUMTATS here:

http://www.rcgroups.com/forums/showthread.php?t=233250

[dogon1013]

I finally started it up,

no load current on 3S is only 0.75 amps. not sure the RPM but it wasn't much. I still need to drill out a 6mm prop adapter before I do more testing.

[dogon1013]

got some more simple data, no rpm data yet though.

3S(11.1V)-3.4amps-Master airscrew 14*9*3
3S(11.1V)-4.1amps-APC 16*10
5S(18V)-7.2amps-APC 16*10

It looks like I am going to need a much bigger prop, more voltage, or to gear it up. I'm only setup for a 5S system max (Pheonix 35) so I will try a larger prop and then probably try to gear it up, before investing in a HV setup.

Another possibility is to change the termination to Delta, as it comes from the factory in Y termination.

[dogon1013]

here are some Pix of the finished motor with the APC 16*10 prop.

No load current on 18V is 1amp

i also attached the 20*12 prop and got just over 10 amp draw at 18V.

I think I am gonna work on designing a gearbox for it as i can't really afford to up the voltage right now, plus I don't have anything that can use a 20" or larger prop.

Later today I am meeting a friend at the field with a tachometer so i can get some more complete data.

[dogon1013]

got some RPM data. It aligns with what the KV rating is supposed to be.
volts and amps measured with a watt meter this time.

3,400rpm-APC16*10-17volts-7.2amps

3,600rpm-masterairscrew 14*9*3-17.3volts-6.4amps

[Chuck McHugh]

got some RPM data. It aligns with what the KV rating is supposed to be.
volts and amps measured with a watt meter this time.

3,400rpm-APC16*10-17volts-7.2amps

3,600rpm-masterairscrew 14*9*3-17.3volts-6.4amps
Toby, it is looking like your motor would work well with my Tri-Pacer:)
Chuck
BTW how was the flying today?

[dogon1013]

Yea i think this motor will work well with that large tri-pacer. flying was OK, though i hit carlos's wing and one of MY control rods was ripped out, and my wing crashed......oh well, can't win em all.

I just finished re-terminating the motor. I changed it to Delta termination. if i remember correctly this should raise the KV and lower the Rm by about a factor of 1.7 (sqrt of 3). I just ran it up and got much better results. The Kv should now be something like 366.

no load amperage on 3S is now 1.7 amps
no load on 18Volts is now 1.9 amps
3S-14*9*3-12amps.

this is as far as i got since my amp meter can't do much above 10 amps.

tomorrow i will try more testing.

[guapoman2000]

Yea i think this motor will work well with that large tri-pacer. flying was OK, though i hit carlos's wing and one of MY control rods was ripped out, and my wing crashed......oh well, can't win em all.
.

He He He......Yeeee Haaaaaaa :D

[dogon1013]

here is some more test data on the Delta version of this motor.
volts and amps measured with an in-line watt meter.

3S
14*9*3 prop-10.7volts-12A-3,750rpm

4S
14*9*3-14.8V-19A-5,000rpm
16*10-14.6V-25.5A-4,740rpm (71oz thrust calculated)
20*12-13.5V-36A-3,400rpm (throttle was not at full, due to max amperage of speed control being reached) (89oz thrust calculated)

The motor barelly got warm.

It looks like the Kv is right around 360, as expected.

[fly_boy99]

Delta looks like the way to go unless you want to stick it in a gearbox.

Pretty darn good.

16*10-14.6V-25.5A-4,740rpm (71oz thrust calculated)

44mph and 4.5lbs of thrust will do nicely in alot of conversions.

Maybe a bit more pitch for speed??!!?? ;)

[guapoman2000]

Toby,

Just an awesome project and finding on the inrunner core and super machine job for the case and end bells! :)

Here's some up close pictures showing the quality! :)

[Art Newland]

Awesome job!!

[PlaneCrazee]

[QUOTE=fly_boy99]Delta looks like the way to go unless you want to stick it in a gearbox.
QUOTE]
You'd have to gear it up?! or turn prop off a P51.
Shouldn't this motor be capable of at least a Kilowatt?
very nice job.
I envy you for your skill naed your lathe.

[fly_boy99]

I like guapomans pics as they really show the size of this bugger.

Heck go to 5S and maybe prop down?

:eek: :eek: :eek:

[olmod]

Im sure its better than it looks judging by the size of those timbers and the restriction they will have ;) great job by the way :)

[TeamTEOR]

Sweet project!

[dogon1013]

You'd have to gear it up?! or turn prop off a P51.
Shouldn't this motor be capable of at least a Kilowatt?
very nice job.
I envy you for your skill and your lathe.

Thank you all for the support.

I was thinking of making a gearbox to gear it up, but changed it to delta instead since it was easy to do. 360 KV is pretty good for the .60 size Lancair it is going into, I do plan on using a 5S system. I am planning on pulling about 650watts, though I'm sure it could handle 1Kwatts or more.

A friend of mine, Chuck McHugh, is building a 33% Piper Tripacer and we are gonna try to use one of these motors, in Y termination, on 10S, hopefully pulling close to 65 amps which would be a total of 2400 Watts. He's building it from a kit so it will be a while before it's done.

[dogon1013]

BTW I am looking at the possibility of putting together a kit for this motor. I'll have to investigate it more but i would expect it to be somewhere around $80. this would not include the $65 for the coil and magnets though.

[sneu]

Thank you all for the support.

I was thinking of making a gearbox to gear it up, but changed it to delta instead since it was easy to do. 360 KV is pretty good for the .60 size Lancair it is going into, I do plan on using a 5S system. I am planning on pulling about 650watts, though I'm sure it could handle 1Kwatts or more.

A friend of mine, Chuck McHugh, is building a 33% Piper Tripacer and we are gonna try to use one of these motors, in Y termination, on 10S, hopefully pulling close to 65 amps which would be a total of 2400 Watts. He's building it from a kit so it will be a while before it's done.


You might take a good at OHMs law and the winding resistance before you talk about 65 amps and 2400 watts:)

From what I can see you may well get the following result:

.12 ohms X 65 amps = SMOKE!

Kidding aside--take a look at other motors that can run at 65 amps and you will see the winding resistance is much lower--more like .010 -.03 ohms.

Steve Neu

[dogon1013]

Yea, that is worrysome. There will be plenty of testing before anything flys though.

[dogon1013]

did some no load RPM measuremens on the delta wind motor. got 4700rpm on a 3S lipo pack.

This would suggest a KV closer to 430, instead of 360 as previously expected. I'll double check the voltage of that pack later today.

[AeroDude]

dogon1013,

your motor is an awesome piece of work!

I have a general inrunner question, I have several small BL inrunner motors, Himax 2015 and 2025 size, I have had problems with the wires and connectors and had to trim the wires down a little, Himax says not to shorten the wires,

what is the effect of the length of the wires out of the motor? Do they all have to be the same length? can the be cut down just outside the motor case and new wires soldered on? does it have to bee the same type of wire in the windings?

I'm an Aero Enganear, not a EE, under stand the basics but don't know all the critical design requirements,

Please help

AD

[sneu]

dogon1013,

your motor is an awesome piece of work!

I have a general inrunner question, I have several small BL inrunner motors, Himax 2015 and 2025 size, I have had problems with the wires and connectors and had to trim the wires down a little, Himax says not to shorten the wires,

what is the effect of the length of the wires out of the motor? Do they all have to be the same length? can the be cut down just outside the motor case and new wires soldered on? does it have to bee the same type of wire in the windings?

I'm an Aero Enganear, not a EE, under stand the basics but don't know all the critical design requirements,

Please help

AD

The warning has to do with the fact that the insulation is very hard to remove and if you shorten the motor leads too much you will have to strip the insulation again--which most people have trouble with.

It has nothing to do with motor performance.

Steve

[AeroDude]

Steve,

the insulation is apparently part of my problem, can't get the wires to solder properly, what is the best way to remmove the insulation?

AD (also Steve)

[dogon1013]

i always use a razor blade to remove the insulation on wires. Just cut a circle and pull the unsultaion off. Unless it is magnet wire, then i use the razor blade to scrape the top layer of insulation (and a little copper).

The wires on my motor came rather long, I shortened them a little when i changed to delta termination. You would want the wires to all be relatively the same length. if one wire was 2 or 3 times the length of the others you might have problems, as the resistance would be different. a small difference in length should have little or no effect. IMO

You will find that there are few "critical design elements". One of the first motors i built was a mess, shaft was loose, stator missaligned,...it still worked, and even flew. I have even extended the wires on one brushless motor about 4 inches without any problem....Some believe it can cause premature failures to the ESC but i have not had problems.

[AeroDude]

Thanks guys!

AD

[Prof. Maneuver]

i always use a razor blade to remove the insulation on wires. Just cut a circle and pull the unsultaion off. Unless it is magnet wire, then i use the razor blade to scrape the top layer of insulation (and a little copper).

The wires on my motor came rather long, I shortened them a little when i changed to delta termination. You would want the wires to all be relatively the same length. if one wire was 2 or 3 times the length of the others you might have problems, as the resistance would be different. a small difference in length should have little or no effect. IMO

You will find that there are few "critical design elements". One of the first motors i built was a mess, shaft was loose, stator missaligned,...it still worked, and even flew. I have even extended the wires on one brushless motor about 4 inches without any problem....Some believe it can cause premature failures to the ESC but i have not had problems.

Careful folks! As Steve N. instructed, the usual motor wire exit per phase is many strands of magnet wire twisted, stripped and tinned using a solder pot or a fancy mechanical device to strip each strand prior to tin. If you cut the bundle "upstream" of this tinning and then tin the outside of the bundle, you won't have the inner strands electrically connected which will severely degrade motor performance.

Good Luck to You,

Steve M.

[dogon1013]

I didn't realize it was multistranded magnet wire...That does make it a pain to cut and strip.

Sometimes you can burn the coating off in the act of soldering (works well with Radio Shak magnet wire) but the coating may be heat resistant on that motor

[dogon1013]

I got some more no load RPM data and double checked it. (used a calibrated stroboscope)

at 11.8 volts and 1.7amps it is turning 4782rpm

put the numbers in MUMTATS and got a KV of 411....a little higher than expected.

I've also been playing with a mount design.
This one is made from bolted together extruded aluminum angle that you can buy at the hardware store. I'm sure plenty of lightening wholes will be drilled in it, but i didn't put them in yet.

[dogon1013]

BTW I am nameing this motor the BFI 5628 motor (Big "freakin" Innruner, 56mm stator OD, 28mm stator length) for now.

[guapoman2000]

More pictures!!!!

[ScubaSteve]

Toby,

Nice work as usual! You might have mentioned it, but I probably missed it looking at all the perty pictures. :) Can you, from best you can tell, determine the individual stator lamination thickness?

steve

[dogon1013]

Hey steve,

I'll see if i can measure it when i get home.

BTW I just purchased batteries for this motor's first flight. Got the Polyquest 20's comming. gonna be a 5S2P 2400mah pack. (48 amps max continuos)

[ScubaSteve]

mmmmmmmm :)

[dogon1013]

just measured the laminations. not a real accurate measurement with calipers but 0.3mm seems to be the number.

[sneu]

just measured the laminations. not a real accurate measurement with calipers but 0.3mm seems to be the number.

.014 is the usual stuff--the good stuff is .007

Steve

[dogon1013]

my measurement was just visual. I put the calipers up to the back of the stator stack and looked close. I'll try the comparator at work but i don't expect it to change by half.

[dogon1013]

I added lightening holes to the mount system... Not sure if i will drill all those holes but it looks nice.

[dogon1013]

just did the calculations, all those lightening holes only save 0.62 ounces(2.26oz vs 2.88oz), so i don't think i will use them.

I bet Alumium nuts and bolts would help though.

[hermperez]

what are the dimensions of that aluminum l channel?, that stuff comes in handy for all sort of things.. brackets, strut attachment points, corner reinforcements. Will have to look in the hardware store again.. the stuff I usually see is too large.

Herm

just did the calculations, all those lightening holes only save 0.62 ounces(2.26oz vs 2.88oz), so i don't think i will use them.

I bet Alumium nuts and bolts would help though.

[dogon1013]

It's about .5" X .75" X 1/16" thick L channel. It is light, I'm not sure I believe the weight the software gave 100%, but it is usually close.

It is what I used to mount the motor to the 2 by 4's on my test stand.

[hermperez]

its perfect!

Herm

It's about .5" X .75" X 1/16" thick L channel.

[Fourdan]

First, I would like to point out that this is not a beginners project, It requires Lathe and Mill work.


I recently talked with someone at an industrial brushless motor design and manufactureing company (Applimotion Inc.) about purchaseing Stator material to make my own large outrunner brushless motors for use in RC planes or helicopters. Although they did not have any stator material for me they were interested in RC electric flight. They just so happened to have several motors that did not meet design specs for some medical device (A small cut in the insulation of one wire), but might be perfect for a large RC power plant. This is what I am now trying to build.

Applimotion only makes the stator and magnet assembly to be built into some electrical device. So now it is up to me to build a case and shaft for this new motor.

The specs given for this motor are:
OD: 2.2"
ID: 0.97"
Stator Length: 1.1"
Res: 0.12ohm
Ke: 4.7 V/Krpm (this is equivalent to 212 RPM/Volt)
Kt: 6.4 Oz-In/Amp
Number of magnet poles: 8
Number of Stator poles: 12
Max Voltage: 200V
Max Cuurent: 65Amps
Max recommended RPM: 6,000 (I was told that above 6K it will loose efficiency)

cuurently I plan on feeding it 18Volts and pull up to 35 amps for a total of about 630watts.

I am calling this the BFI 5628

Hi
Very interesting project, congratulations
Do you have a picture showing the magnets-cylinder with the 8 mm shaft
Is it a 8mm hole inside?
Louis

[dogon1013]

....the good stuff is .007

Steve

Would the "good stuff" you are refering to be the ones used in Neu motors :D ;)

I finally put 2 and 2 together. I didn't realize who you were. Thanks for that very informative article in quietflyer, it's not often that the manufacturer will dissect their own product and explain how it is built.


I measured the laminations on a comparator and got .35mm which i suspect is actually .014"

[dogon1013]

I'll see if i took some pictures of the magnet cylinder and back iron when i get home. 2 of the magnet cylinders are actually in the first picture in the first post of this thread and the back iron is just a piece of metal with an 8mm hole in the middle.

[dogon1013]

didn't find any pictures of the back iron, but like i said, it's nothing special. I could probably have saved a good amount of weigh by makeing the back iron hollow, but i didn't.

I did get the batteries for this motor. 5S2P Polyquest 20 2400mah total. I ran some no-load tests.

20.5volts
1.80 amps
8100 rpm

this puts the Kv at around 400 rpm/volt. It is spinning faster than the designers suggested but the rpm should be lower with a prop on it.

[dogon1013]

Just finished some more testing with the help of Carlos (guapoman2000) using my Polyquest 5S2P 2400 pack.

14*9*3-17.4V-25A-435W-5800rpm

16*10-32A-17.5V-560W-5400rpm

20*12-36A-16.8V-604W-3400rpm (could not go to full throttle due to 35A speed control used)


I'm trying for 650W to 750W so I will try a 15*12 or 16*12 prop next.

[guapoman2000]

Super testing Toby!

I did not find the propeller size/pitch in the APC "Sport" style like we talked about, however, the Pattern does have many sizes for what you are looking for!

I am assuming that the "W" stands for Wide and "N" stands for Narrow?


I think the 15.5 diameter will provide a good mix!

Oh, yes, they do have a 16 X 12 as well. ;)

[guapoman2000]

The super Large Graupner 20 X 12 Wood Propeller sounded like a Glow Model taking off!!! That propeller provided just insane thrust! At first, I was afraid of placing my hand with the sissy Great Planes Techometer! :D Toby only had three threads of Prop adapter coming out at the other end of that prop! :eek:

[Daveairway]

Toby,

This is just a quick “thank you” for posting your motor build thread. I have been following since day one, and the motor looks great!

This is the first testing – but you may want to check this thread – if all turns out good with these power tool batts – they might work well with your motor. http://www.rcgroups.com/forums/showthread.php?t=456011

Carlos,

Thanks for the nice pictures and the close up. Toby’s motor should pull that foamie just fine – wait – it is not a foamie – it is a Rubbermaid cooler :)

Looking forward to flight reports and pix of the motor mounted, ready for the motors maiden flight.

Dave

[dogon1013]

Thanks Dave, I have been following that thread and looking at those batteries too.

Yea, there is a full case of soda in that cooler to act as ballast, without anything in there it probably could take off :)



BTW. Here is the build thread of the plane that it is going in. A re-built great planes Lancair 60.
http://www.rcgroups.com/forums/showthread.php?t=467016

[myk]

20*12-36A-16.8V-604W-3400rpm (could not go to full throttle due to 35A speed control used)


I'm trying for 650W to 750W so I will try a 15*12 or 16*12 prop next.

Not sure if you realize it or not, but by running your 35A speed controller at less than full throttle to try and keep the "average" amps below 35 is a not good for it and probably worse than running it at full throttle with that setup. A BL speed controller is always sending the motor full throttle current, it just varies the amount of time that it is doing it, so even though your watt meter is reading 36amps that is just an average, the actual "on" current is whatever it is at full throttle.

Mike

[guapoman2000]

Not sure if you realize it or not, but by running your 35A speed controller at less than full throttle to try and keep the "average" amps below 35 is a not good for it and probably worse than running it at full throttle with that setup. A BL speed controller is always sending the motor full throttle current, it just varies the amount of time that it is doing it, so even though your watt meter is reading 36amps that is just an average, the actual "on" current is whatever it is at full throttle.

Mike

Excuse me....no one messed with the Pulse Width Modulation (known as the "Duty Cycle"), a programmable feature in CC ESC's. Therefore, the onboard FETs are not getting turned "on" had he programmed the PWM at a higher rate. Also, timing was not messed with either so, I really don't think he will be burning up that ESC anytime soon and for short static burst "AT" full throttle like we performed last night. Not a problem.

The motor is rated at 65 AMPs and at 200 Volts, correct me Toby, if I am wrong here. ;)

Carlos :rolleyes:

[dogon1013]

I did blip the throttle to full for a second with that large prop and i was pulling 40+ amps at that point.

I don't plan on using that prop for testing anymore (it's just too big). But thanks for the warning.


I would say that the Windings are rated at 65A and 200V max. Don't really know what the motor can handle in an RC environment ....yet :D

[sneu]

The motor is rated at 65 AMPs and at 200 Volts, correct me Toby, if I am wrong here. ;)

Carlos :rolleyes:


Let me raise the flag here--200 volts and 65 amps:) 13000 watts--17 hp??? Not likely in this universe from that motor!


With a winding resistance the losses at 65 amps will be unsustainable for more than a short run before it overheats.

Steve Neu

[dogon1013]

I agree that it probably can't handle both 200 volts and 65 amps... and I'm not willing to test it either, i'll leave that to someone else.

[guapoman2000]

Let me raise the flag here--200 volts and 65 amps:) 13000 watts--17 hp??? Not likely in this universe from that motor!


With a winding resistance the losses at 65 amps will be unsustainable for more than a short run before it overheats.
Steve Neu

Yeah, I agree as well :D According to Tody that's what they told him the specifications were and I would perhaps say that's amazing at best for a motor to sustain this kind of values.

Mr. Neu,

You mean before there's a short in the windings! :D

-----------------------------------------------------------
Nevertheless, we have been quite impressed with the motor itself with the bench testing that has been conducted so far and with actual battery packs instead of power supplies.

Carlos :cool:

[myk]

Excuse me....no one messed with the Pulse Width Modulation (known as the "Duty Cycle"), a programmable feature in CC ESC's. Therefore, the onboard FETs are not getting turned "on" had he programmed the PWM at a higher rate. Also, timing was not messed with either so, I really don't think he will be burning up that ESC anytime soon and for short static burst "AT" full throttle like we performed last night. Not a problem.

The motor is rated at 65 AMPs and at 200 Volts, correct me Toby, if I am wrong here. ;)

Carlos :rolleyes:


He will very likely burn up the ESC trying to limit the current with partial throttle, and you obviously don't know how a brushless ESC works. Here is some light reading for you:

http://www.rcgroups.com/forums/showthread.php?t=435452

another:

http://www.rcgroups.com/forums/showpost.php?p=3864320&postcount=37

one more:

http://www.rcgroups.com/forums/showpost.php?p=3859514&postcount=19

OK last one incase you believe Steve over Patrick :)

http://www.rcgroups.com/forums/showpost.php?p=3858591&postcount=16

Mike

[guapoman2000]

Mike,

Correct, like I said, it depends on PWM and Patrick is correct.

http://www.rcgroups.com/forums/showpost.php?p=4534404&postcount=11

The average "On" for our test purposes will not burn this ESC. The type of motor (inrunner) and the design of Toby's ESC PHX-35 has electronics that dissipates heat very well, especially for testing purposes!

I am very familiar with ESC's that burn if you don't have the proper ESC design (Hardware components and/or programming) for heat dissipation as I was one of many that used a Park 370 Outrunner and an Early CC PHX-25 that burned up with partial throttle and did not have anything to do with surpassing it's maximum AMP capacity but, rather had everything to do with the type of motor "Outrunner" and the inability of the ESC to dissipate the heat generated by this type of Brushless motor at patial throttle. Again, Toby is Testing this motor and NOT going to place it in a model with the setup presently configured and besides Toby was not keeping the throttle at partial but, at Full! ;)

I think we are perhaps saying the same thing but expressing them in different terms and this thread is for Toby's new motor and lets allow him to continue and update all of us with the actual testing results of this super motor.

Should you like to continue with the Electronic lesson for me, I welcome you to take it off-line and PM "or" e-mail me.

Thank you!
Carlos

[AeroDude]

Hey dogon1013,

I had another basic BL motor question for you, I have an E-Flite Park 400 motor that when installed in the gbx w/prop on would twich back and forth, I'm using a CC 25 amp speed control which works fine with my other motors, if I take the motor out of the gbx it runs fine, but with the load on it just twiches back and forth, is this an indication of short in the windings or a bad connector?

AD

[myk]

Mike,

Toby was not keeping the throttle at partial but, at Full! ;)

Thank you!
Carlos


That is absolutely not true, go back and take a look at post #75, it clearly explains that he could not go to full throttle for fear of exceeding the ESC current rating. I was merely trying to help him not burn up his speed control by putting it in this situation. I think you are arguing with yourself at this point so I see no need to further the conversation.

Mike

[dogon1013]

Mike,

Thanks for your input on the ESC issue. I did limit the use of that prop. But the only way to know if it would pull to much current is to test it, and it did.

Aero dude,

you might be over proping it in the Gearbox, otherwise you might have a loose wire in a connector. I have had this happen before. I swore it was the motor when it happened, but it turned out to be a broken solder joint that was hidden in shrink wrap.

[guapoman2000]

Toby,

I looked in my hobby tool table and the largest propeller I have as I imagined was the APC "E" 14 X 10 so, we need to hunt for the ones you mentioned.

Also, I will be able to meet you and try out that CC PHX-35 again and perhaps go full throttle again! :D ;)

Carlos :rolleyes:

[guapoman2000]

Aero dude,

you might be over proping it in the Gearbox, otherwise you might have a loose wire in a connector. I have had this happen before. I swore it was the motor when it happened, but it turned out to be a broken solder joint that was hidden in shrink wrap.

Yes, indeed...I have had my share of this type of experience and everytime it was a loose connector.

Carlos

[AeroDude]

Thx guy's, a loose connector is what I suspected it to be, I'm not over proping, I pulled off the Park 400 and replaced it with a Park 370 and it works fine. I have take apart the Park 400 and checked out the magnet to ensure it was'nt craked or chiped. I un-soldered the connectors cleaned the wires and re-soldered them back ensuring good connections. I have'nt tested the motor yet, I installed it into a 6.6:1 gbx, I will test it using my CC Phx 25 ESC. I have had motors hesitate at low throttle before but never twitch back and forth at WOT! These motors are very simple and easy to repair.

AD

[dogon1013]

worked on the mount today.

I just noticed i installed the side pieces upside down from what i drew.... Oh well. at first i wasn't gonna drill the lightening holes, but I had the drill out so i just drilled them.

Everything lined up great, no need to enlarge any holes, it all just fit the first time. (gotta love the 3D design software)

[guapoman2000]

Super Job, Toby!!!! :p

[z-matrix]

Windings does not care about voltage while your motor is running as far as the insulation can handle it, since most of the power should be converted to magnetic thrust, by the coil's imaginary power dissipation.
So no problem as far as the speed controller regulates the current below a safe level.

if you have 3x0.12 ohms,
at DC current wire will dissipate I*I*R power.
Y - 32.5 Amps:
253.5W per 2 phase in series (0.24 Ohm) (7.8V DC) - 169W Average per 2 phase
Y - 65 Amps:
1014W per 2 phase in series (0.24 Ohm) (15.6V DC) - 676W Average per 2 phase
đ - 65 Amps:
338W (0.08 Ohm) (5.2V DC)
đ - 130 Amps:
1352W (0.08 Ohm) (10.4V DC)

đ gives more RPM per volt than Y because of the lower inductance, and lower resistance, but also needs more RPM to provide same EMF,
though EMF windings can be used, using 0.05mm wire...

depends on the core how much power will be dissipated overall, eddy currents, hysteresis loss can be more than wiring loss ( and it probably will be more at high RPM, with low wiring resistance )

i think you might consider re winding, using thicker wire, if you want more power, efficiency, at less voltage, since it was wound for 200V.
Btw it is possible to wind this motor for a magnet ring with less poles (2),
so you whould have a turbine ;)
inrunners are used where very high RPM is needed, how whould it feel to use your motor above 40k RPM?
sorry for coming again with Ohm's law in a motor, but it is nice to know your motor whould take the currents in DC too, of course, you do not run your motor with a current generator.

[Ron van Sommeren]

Higher efficiency does not only mean that the motor makes better use of the batteries' power, it also means the motor is able to handle a higher power input before hitting its maximum temperature mark.
An example:
Say the motor has an efficiency of 70% and it can handle 50Watt input. That means it can get rid off 0.3*50=15Watt excess heat. Now, by cramming in thicker wire, efficiency increases to say 75% (I'm a bit optimistic here). The motor's ability to loose those 15Watts has not changed (by radiation, convection and conduction). This means the motor now can handle 60Watt before it hits the 15Watt (0.25*60Watt) losses mark. An efficiency increase of 5% gives an increase in the power to weight ratio of 20% (from 50Watt to 60Watt). That's why efficiency plays such an important role, in any motor design: efficiency governs maximum power.

Do-it-yourself motor homepages, manuals/tutorials, checks and tests in the first message of this motor builders tips and tricks thread. The checks and tests may save you from frying your controller or motor. Thread is active, bookmark it for future refence and subscribe to it:
http://www.rcgroups.com/forums/showthread.php?t=240993


Vriendelijke groeten ;) Ron
• diy motor building tips & tricks (http://www.rcgroups.com/forums/showthread.php?t=240993)
• diy outrunner discussion group (http://www.yahoogroups.com/group/lrk-torquemax)
• int. E fly-in & diy outrunner meet (http://home.hetnet.nl/~ronvans/), June 25 2006, Nijmegen, the Netherlands
Vriendelijke groeten ;) Ron

[dogon1013]

This motor was not designed for 200 volts. that number was just given to me as the absolute max the winds can handle.

The motor was not designed to spin faster than 6,000 rpm. It was designed for torque. working back from the max rpm and original KV i would deduct that the motor was designed for 28V max.

the generalization that inrunners are used where very high rpm is needed may work for smaller diameter motors, which necessitate the use of less poles. but when you increase diameter of any motor (innrunner or outrunner) you have more room for larger pole counts and therefore the ability to design for torque, not just rpm.

I'm not sure I agree with everyone using Ohms law for DC current to analyze an AC circuit. Sure, it will give a general idea of what will happen but it is not accurate without taking impedance and time into account.
.....I prefer testing anyway :D

[z-matrix]

This motor was not designed for 200 volts. that number was just given to me as the absolute max the winds can handle.

The motor was not designed to spin faster than 6,000 rpm. It was designed for torque. working back from the max rpm and original KV i would deduct that the motor was designed for 28V max.

the generalization that inrunners are used where very high rpm is needed may work for smaller diameter motors, which necessitate the use of less poles. but when you increase diameter of any motor (innrunner or outrunner) you have more room for larger pole counts and therefore the ability to design for torque, not just rpm.

I'm not sure I agree with everyone using Ohms law for DC current to analyze an AC circuit. Sure, it will give a general idea of what will happen but it is not accurate without taking impedance and time into account.
.....I prefer testing anyway :D


it might be an option to analyze a core less inrunner,
but since in most cases you do not even know what kind of core you have in your motor, you are shot with this.
Of course, experiments don't lie, just wind and measure ;)
if glows bright and smoke then wind again.

[guapoman2000]

Toby,

You posted this picture of Chuck's former Great Planes Lancair ES (80 inch wing span) at our Club Talk thread.

However, you seemed to forget to post it at this thread for the motor and well, I could not help it.... :D

Let's get that Motor and crashed model (By the Way...super repair job!!) in the air and see what happens! You of course need a few items left for the model such as servo covers and a new wind shield. :D

Seems like the motor, servos are in, however!!!

Can't wait to see it in the air!! :p

If it does fly...we will call it the PHOENIX with a new motor! :p

http://www.flightofthephoenix.com/