HKIII 4035

[_Dekker]

This was the first Scorpion stock motor I took apart. I had some bad experience with taking apart a 4025 once, but now I was prepared and used the freeze method for pulling the stator from its carrier.
Goal was optimizing the cooling of the motor, with same n spec: 500rpm/V
There have been some reports of this motor burning up because of the heat, quite logical if you see how packed the stock winding is:


The weight of all the copper that came off: 73gr.


This 500rpm/V version had 10 windings in D. The bundle consists of 21 wires with 0.29mm diameter. With this, the copper surface in one slot is 13,9mm^2, not bad at all.
I did this motor in 5+6YY, that resulted in a 510rpm/V n spec.
Wire diameter used was 1.4mm, with excellent cooling and a 22% copper surface increase over the stock version. I often use CAD to investigate the wire fill:


In practice the wind fitted even better than the CAD picture predicted, the stator is just perfect for this wind:


All tests OK and meanwhile the happy owner uses it in a GAUI X7:

[_Dekker]

Meanwhile I took apart another HKIII 4035. Looks like Scorpion is improving reliability on their motors:
Now they put in isolation disks on top of the stator to prevent the wires shorting towards the stator carrier:

[GMAURO]

GOOD WORK Dekker! Very nice "open space" for increase cooling. Have you tested effective kv? This latest hk3 series is very good and optimized project. I've rewound some of this, and is amazing. 1.5 wire put easly into the slot with zig-zag winding.
This rewinded motor have very big performance...

[Stolla]

Nice!, my favourite motor, not to rewind, that distinction goes towards mx, but performance wise the 4035 is just perfect for a90 size machine and never a problem with jive.
I have another on the pipeline for tdr exclusive speed machine, what you guys reckon 5+5 in 1.6 mm.? My 5+6 gave me 515 kv on pjazz, temps after hard flying ambient 25 c +-65 c which is not bad considering 2200 headspeed in my 7 hv, what kv you got there Bert, and what esc?

[_Dekker]

Originally Posted by GMAURO

GOOD WORK Dekker! Very nice "open space" for increase cooling. Have you tested effective kv? This latest hk3 series is very good and optimized project. I've rewound some of this, and is amazing. 1.5 wire put easly into the slot with zig-zag winding.
This rewinded motor have very big performance...

Thanks!
What do you mean with effective kv? I did not measure the original, but if I calculate back it must have been around 485 (500 specified)

Originally Posted by Stolla

Nice!, my favourite motor, not to rewind, that distinction goes towards mx, but performance wise the 4035 is just perfect for a90 size machine and never a problem with jive.
I have another on the pipeline for tdr exclusive speed machine, what you guys reckon 5+5 in 1.6 mm.? My 5+6 gave me 515 kv on pjazz, temps after hard flying ambient 25 c +-65 c which is not bad considering 2200 headspeed in my 7 hv, what kv you got there Bert, and what esc?

Yes the MX is easy, less preparation. Only 'thing' about the mx is that it has smaller bearings compared to the Scorp. The Kv of this 4035 is 510 (it's in the text somewhere above). My test esc is a Turnigy Plush with default settings, it matches well with the YGE 18deg setting.
A 5+5 should give you around 567 n spec if you previously had 515.

Bert

[Stolla]

You've done 1.6 before if I remember correctly Bert, 5+5 reasonable fit?

[_Dekker]

Yes I did 5+6 in 1.6mm, but that is really pushing it, no room for errors at all (BTW it is for sale):


5+5 should fit just fine.

[Stolla]

well that it's indeed a job well done, does it run measurably hotter than 1.32-1.4 mm.?
Also have you any logs on this motor?

[_Dekker]

The only feedback I have is that after a 3D flight the pilot could hold the motor without burning himself. I have seen a video where it was used in a Compass HV7 but I did not get the impression the motor was used to its full potential, since there was noticeable bogging. I get near zero bogging with my 4225 so it must have been a thing with the governor setup or timing settings.

[Stolla]

isn't it strange how people still don't get the gov thing right, they don't understand that not enough headroom even Ralphs 4540 monster will drop headspeed (sorry Ralph) . I have the same winding in 1.32 on my 7 hv no bogging, it's a monster. Have you jive and jlog Bert? I think it's a rewinders must have for a perfect setup, keep pwm under 100% and you won't believe how little headspeed drops under load, hit 100%, and wham, big drop in rpm. The sad thing it's that a well governed "weak" motor will outperform a badly governed monster.

[GMAURO]

Originally Posted by _Dekker

Thanks!
What do you mean with effective kv? I did not measure the original, but if I calculate back it must have been around 485 (500 specified)



Yes the MX is easy, less preparation. Only 'thing' about the mx is that it has smaller bearings compared to the Scorp. The Kv of this 4035 is 510 (it's in the text somewhere above). My test esc is a Turnigy Plush with default settings, it matches well with the YGE 18deg setting.
A 5+5 should give you around 567 n spec if you previously had 515.

Bert

Hi Dekker, sorry for my write error, i wanted to write "actual" Kv after rewind.

[GMAURO]

Originally Posted by _Dekker

Yes I did 5+6 in 1.6mm, but that is really pushing it, no room for errors at all (BTW it is for sale):


5+5 should fit just fine.

WOWWW!! Nice job Dekker! My complyments for this "brutal" winding!

[GMAURO]

Originally Posted by Stolla

isn't it strange how people still don't get the gov thing right, they don't understand that not enough headroom even Ralphs 4540 monster will drop headspeed (sorry Ralph) . I have the same winding in 1.32 on my 7 hv no bogging, it's a monster. Have you jive and jlog Bert? I think it's a rewinders must have for a perfect setup, keep pwm under 100% and you won't believe how little headspeed drops under load, hit 100%, and wham, big drop in rpm. The sad thing it's that a well governed "weak" motor will outperform a badly governed monster.

Hi Stolla, I totally agree with your opinion. Specially with jive series esc low throttle curve, for good pwm work, is the better way for governor optimize.

[_Dekker]

Originally Posted by Stolla

isn't it strange how people still don't get the gov thing right, they don't understand that not enough headroom even Ralphs 4540 monster will drop headspeed (sorry Ralph) . I have the same winding in 1.32 on my 7 hv no bogging, it's a monster. Have you jive and jlog Bert? I think it's a rewinders must have for a perfect setup, keep pwm under 100% and you won't believe how little headspeed drops under load, hit 100%, and wham, big drop in rpm. The sad thing it's that a well governed "weak" motor will outperform a badly governed monster.

I have a Jlog but sold my Jive, it was a 80hv, not enough for the motor I'm running now.
Since I'm using hv servo's and the Vbar gov now I see more use for an YGE 160HV (which is on the way, the 120HV I'm running now runs very hot), but indeed no way of checking PWM and also the performance at low rpm's is not as good as Jive.
If only the Jive had HV BEC, than it would have been a serious candidate for me.
What do you guys use with the Jive, internal governor or Vbar gov?

[Stolla]

Bert with jive i use internal, external i use the fusionhawk 120hv(robbe roxy, megapower, and now os) it seems to work very well on my friends x7 with my 5020 1.6mm wind and also e8 on mx 1.32 winding, same as Timo wendland ran on tdr and 4525. My 120 hv jives still runs every motor and doesnt get how so with jlog its fantastic to get perfect setup, but there are other options for sure. I dont mind hv too much all the tests i've seen they reckon cant feel the difference? What bothers me about yge is the only 6month warrantee, and they seem to be working not as well as jive. Right now the best i've seen to protect your equipment is jive and for cheapie i've yet to see a fusionhawk failure, please let me know if you guys see one, maybe the fan has something to do with its performance, although didnt help my black edition powerjazz with the 5020! haha

[velocity90]

Originally Posted by Stolla

Bert with jive i use internal, external i use the fusionhawk 120hv(robbe roxy, megapower, and now os) it seems to work very well on my friends x7 with my 5020 1.6mm wind and also e8 on mx 1.32 winding, same as Timo wendland ran on tdr and 4525. My 120 hv jives still runs every motor and doesnt get how so with jlog its fantastic to get perfect setup, but there are other options for sure. I dont mind hv too much all the tests i've seen they reckon cant feel the difference? What bothers me about yge is the only 6month warrantee, and they seem to be working not as well as jive. Right now the best i've seen to protect your equipment is jive and for cheapie i've yet to see a fusionhawk failure, please let me know if you guys see one, maybe the fan has something to do with its performance, although didnt help my black edition powerjazz with the 5020! haha

YGE has 2 years. Maybe outside of Europe its different.

[Stolla]

So I did 5+5 in 1.6 mm, was not easy, my paper is way to thick and hard, also couldn't use my powercroco pliers as not enough space between winds, didn't grind thin enough, anyway kv on fusionhawk 567 kv, both motors tested exactly same,1000 v powerhippo style hehe!. Now on my bansheed tdr...spot the diffs! Bert you have my respect with that 5+6!, no way I can do it, at least not with the truck starter wire and plexiglass I use for paper!

[HeliFX]

thats any interesting photo of your TDR you have there Stolla

am I missing something or does the TDR now come with a belt drive to motor
or that a banshee bastard child.

Did you do the mod yourself ?

Originally Posted by Stolla

So I did 5+5 in 1.6 mm, was not easy, my paper is way to thick and hard, also couldn't use my powercroco pliers as not enough space between winds, didn't grind thin enough, anyway kv on fusionhawk 567 kv, both motors tested exactly same,1000 v powerhippo style hehe!. Now on my bansheed tdr...spot the diffs! Bert you have my respect with that 5+6!, no way I can do it, at least not with the truck starter wire and plexiglass I use for paper!

[Stolla]

its made by fellow heli freaker HSC. His gear stripped on tdr and he made a plan. To be honest the secondary gear on the mainshaft takes more stress than this one but it also is stronger. Benefit here is motor heat doesn't destroy the gear, also the flex on tdr frames with monster motors is not an issue as with gears. Downside is obviously more resistance but not a problem with stronger motors as we see on banshee. The work on this mod is out of this world tolerance wise, the main pulley is split for upper and lower halve to be able to machine flanges so they don't fly apart like on the goblin (they have a fix now)
Idler pulley keeps belt tight and more teeth in contact. tolerances are so tight that plans to machine in China came to nothing. Cost wise sounds expensive but in reality the cost of a good motor. Still haven't flown yet though but I believe its quieter although I'm hoping for a bit of banshee scream!

[HeliFX]

sure is nice. At first i thought it was a re-purposed Goblin part. Well with the current trend and high power system I'm a firm believer that belts are the way to go.
Just be thankful your not putting these motors in a Logo 600.
Any logo owner know to bring a bag full of extra gears to field. A specially if your running beyond its 10S specs.

Originally Posted by Stolla

its made by fellow heli freaker HSC. His gear stripped on tdr and he made a plan. To be honest the secondary gear on the mainshaft takes more stress than this one but it also is stronger. Benefit here is motor heat doesn't destroy the gear, also the flex on tdr frames with monster motors is not an issue as with gears. Downside is obviously more resistance but not a problem with stronger motors as we see on banshee. The work on this mod is out of this world tolerance wise, the main pulley is split for upper and lower halve to be able to machine flanges so they don't fly apart like on the goblin (they have a fix now)
Idler pulley keeps belt tight and more teeth in contact. tolerances are so tight that plans to machine in China came to nothing. Cost wise sounds expensive but in reality the cost of a good motor. Still haven't flown yet though but I believe its quieter although I'm hoping for a bit of banshee scream!