something new

[HeliFX]

Ralph wow very nice,

May I ask which ESC have you been testing with and with this new configuration
have you found much more reliable and consistency with the ESC in use .

is also a custom stator design.
I would guess so too fit the larger bearings

[powercroco]

built only for fun:

a "chimera" between 40mm high (double pyro 800) stack and HK 5040 magnetsystem + housing.

only an adapting ring 25mm->20mm was needed to realise the project.

[omerco]

Ralph
What is the effect of that stator having less iron compared to the orihinal scorpion? Less torque?

[powercroco]

less iron = primary less iron losses
less iron = also less area to lead magnet flux

for this special shape:
this shape is optimized for 14 magnetpoles (and for machine winding).
means, you need the lower iron losses to compensate the 140% (compared to 10P) basic iron losses.
but it provides also has less room for copper -> less copper -> higher internal resistance for the same number of turns.

in this special test only 4 turns are needed to get the targeted nspec.
With its 1,8YY the motor can use all amps, the battery can give anyhow.
but if there is still enough iron to lead all the generated flux, I will see soon.

in sum the possible differences will be below round about 2-3% in max efficiency and almost no heli pilot will notice such difference in flight.

[Raptorapture]

Very interesting development to combine the two varieties. An opportunity to see where 14P can go - oops, got that one wrong

Love your sig Ralph!

[omerco]

Originally Posted by powercroco

less iron = primary less iron losses
less iron = also less area to lead magnet flux

for this special shape:
this shape is optimized for 14 magnetpoles (and for machine winding).
means, you need the lower iron losses to compensate the 140% (compared to 10P) basic iron losses.
but it provides also has less room for copper -> less copper -> higher internal resistance for the same number of turns.

in this special test only 4 turns are needed to get the targeted nspec.
With its 1,8YY the motor can use all amps, the battery can give anyhow.
but if there is still enough iron to lead all the generated flux, I will see soon.

in sum the possible differences will be below round about 2-3% in max efficiency and almost no heli pilot will notice such difference in flight.

Very interesting indeed. always the game between efficiency and torque.
I would love to hear how it came out!

[powercroco]

n spec as targeted:
457/V with yge fix timed 18°
446/V with jive auto timed.

seen over all it runs really as good as expected.

[powercroco]

to WayFastWilly

no problem at all.

My math is coming up with around 330kv requirement, I see that they have a pyro 850-31, would this be the way to go?

if 330/V would be needed, a 5040 has to be winded with:
6+6x1,7YY winding gives 319/V.
6+5x1,7YY winding gives 345/V
this is makeable with 1,7mm wire for sure.

such motor will generate enough torque also for 950 blades and also for 3D with them.

[WayFastWilly]

I am very interested in one.....

[powercroco]

sent PM to you.

[powercroco]

some project photos:

front of 6+6 x 1,7mm winding



switched for YY backside



the special logo 800 10-8 long shaft was a lot of work!


t

1000V test was okay of course.
now I still have to mount the stator on holder, test it and glue the windings.

found this video about stretched logo 800:

2,20m 3D-Heli - Flug 12 (bildstabilisiert) (7 min 10 sec)

So I think, the project will work - this extremely powerful drive will help of course.
my part just is done:

[WayFastWilly]

Ralph,
You have an amazing talent my friend. When she is ready to fly I will post some photos.
Thanks again for your help........ Bill

[WayFastWilly]

Just a little test flight, not pushing too hard as it is the maiden flight and the whole heli is experimental...... so far all is well.

Parker 950 (4 min 38 sec)

[powercroco]

seems to me, the motor has no problems also with these long blades.

[powercroco]

5040 into banshee:



and into diabolo speed:
http://www.rc-heli.de/board/showpost...&postcount=285

another I winded with 8+7x1,66YY for speedplane.
very good for a lot of volts and big, highpitched props.
target is, to pass the 400km/h with silent less than 7500rpm on prop.

[powercroco]

This 5040 was winded by schmiddi (anotherone member of the german extreme winders community) with 11+11 x 1,4
he terminated the winding "dd".




the copperfilling with this wind is higher as into my 8+7x1,6YY.

he sent me also this drivecalc datasheet:

[apper001]

As a first...have too digest the winding and the numbers here....

[powercroco]

the latest modification of 5040 is a realy low spinning and a bit more efficient variation with statorstack of 0,1mm sife plates and n spec. of only 202/V.

[jamage]

hello gemtlemen, the dual wire detail was brought to my attention some time ago through another member's winding experiments maybe a year or so past. Now I read your motor winding prefers two wire, btw, really like the Parker 950 vid and heli, size and flight, really awesome.

If one were to estimate there's more surface area of two wires 1mm than a single of 1.7mm in this regard one can understand the lower resistance of the 2wire winding. There should also be more copper closer to the stator pole and more cross section of copper, almost like a rectangle wire.

I've read up on litz, plated, square, etc wire options. Cooling is difficult with square pack even though there can be more copper per winding, single large dia winding begins to put less and less copper near the stator surface and as you know flux efficiency is affected by distance.

Personally I want to take on a project and wish to study all possibilities before winding for 12s in a 450 size motor presently wired 4 turns delta x 8 strand. Plan is to wire YY 8 turns 2 wire 20gauge or slightly larger if it will fit. Talk of segmented stators and wire types has recently brought new potential to custom made motors and it's fun to dream of the ultimate motor. The objective is learning and applying the knowledge to bigger and better motors, hv being the key, there's so much to consider not to mind other aspects I don't want to introduce at this time.

This is a very interesting article on the many considerations involved http://engineering.dartmouth.edu/ind.../isie2006a.pdf

Throughout the past few hours catching up reading all the latest topics in this forum I see there's a hunger for better options than the simple ones manufacturers deliver to the public on the cheap. Think if you can take all you've learned and apply it to winding for e-vehicles, what would you do? And how about those d/y motors, there's a project and a half.

[powercroco]

happy new year to everyone!

@jamage:
thanks for your interest!
for such questions there is a new omnipresent star into this forum.
seems to me, it would be better to ask him.
this prevents misunderstandings by language barrier.