Align bl45x + scorpion hk2221-8 very hot

[foekie01]

Hello,

I own a 450 pro v2 helicopter and recently decided to upgrade my heli with a scorpion hk2221-8 motor. In my search for an esc for this motor I came up with the following options'

• Align bl45x 45a
• Castle 50a
• Hobbywing 50a

I decided to buy the align one, because the castle (which has more features, I know) costs twice the amount of money.

Bench testing seemed fine. Motor spooled up nicely, everything was good to go. Mounted everything in my heli and did a test hoover. I noticed, after about 2 minutes of hoover, that both the motor and the esc run very hot. As in you cannot touch them.

I tried to find out what was the cause and the first thing I noticed was that the pinion was slightly too big for the motor shaft. This resulted in a wobbeling pinion which stood out more on one side. Might this be the cause? I ordered a new one which I hope to receive today.

Could it be that the timing of the esc is not ok? The hk2221-8 has 6 poles, so I should select mid timing, right?

I checked everything and all seems to run smooth. No binding in torque tube or what so ever. Could it be the pinion?

Thanks!
Robert

[RC/DC_5000]

Scorpion motors are known to run pretty warm/hot. I think you'd have been much better of with a tunable ESC like Castle offers. That motor specs 5 degrees of timing and 8 pwm (from Scorpions Website).

Because the Align ESC only offers incremental timing adjustments- you're only option is to drop it down to low timing and see if the heat in the ESC gets any better. You have now exhausted your ESC tuning options.

What gearing, throttle curves and battery are you using? These could affect your extreme temps as well. You want that ESC and motor on the smallest pinion possible with the ESC as wide open as possible while still hitting your target headspeed. A well tuned V curve could also reduce the heat build up.

[sconel]

There are two sized motor shafts/pinions for 450's. I think the older ones had 3.17 dia shaft while newer ones use 3.50 shaft. If youre putting a big pinion on a small motor shaft, it wont work at all.

New motor? Never crashed?

[foekie01]

Thanks for helping out!

Scorpion motors are known to run pretty warm/hot. I think you'd have been much better of with a tunable ESC like Castle offers. That motor specs 5 degrees of timing and 8 pwm (from Scorpions Website).

Because the Align ESC only offers incremental timing adjustments- you're only option is to drop it down to low timing and see if the heat in the ESC gets any better. You have now exhausted your ESC tuning options.

Yes they are known to run pretty warm. But really hot as in you cannot touch the motor can't be good. Well I thought about buying a castle but like said did not. Others run this motor on a hobbywing 50A, which does have "advanced timing" config and that might be why that works.

Hobbywing config;

What gearing, throttle curves and battery are you using?

12T on motor, standard 450 align gear with I believe 150 T ?
Throttle curve (normal mode, test curve):

-100
-60
-13
22
60

Pitch (test curve):
-40
0
100

There are two sized motor shafts/pinions for 450's. I think the older ones had 3.17 dia shaft while newer ones use 3.50 shaft. If youre putting a big pinion on a small motor shaft, it wont work at all.

Yes. The new 450's use 3.5, but tis motor uses 3.17

New motor? Never crashed?

New motor yes, never crashed.

Here you can see that the pinion does not fit;

[sconel]

Too close and blurry, but bottom line is....if your pinion is too big for the motor shaft, its GOT to be the wrong pinion. You have any way to measure the motor shaft diamerter AND the inside of the pinion? Dial calipers are kind of a must-have imo.

You CAN NOT use a pinion that's not running true to the motor shaft.

Also am quite curious about why the top of the motor seems to be all chewed up. Wiring insulation look terrible..like it was torn and ripped by the maingear, and appears to be some significant chips or gouges out of the motor top.

You aren't using 6s batteries in a 3s motor, right? Hang in there

[foekie01]

Yes the picture is kind of bad, but cannot edit my post?

The motor is so chopped up, because align makes terrible motor mounts. Basically only align motors fit. Had to modify the motor mount to allow larger screws. The top is ripped up because I had to align the motor correctly with the motor mount and it seems that my fiddling around scratched the top of the motor. The damage is done and in real life you do not see it as good as on this photo. To be honest I have no idea why the insulation is so messed up on the photo. I just checked it and I cannot see the damage as seen on the photo. Maybe I can see it better in the morning.

Yes, the pinion is wrong. Thats what I concluded and stated in my first post.

Anyway. The idea was to show you that the pinion is slightly larger than the shaft. And that is not ok. 3.17mm one is on the way. The new one should arrive tomorrow. Supplier kind of sucks.

[sconel]

Its just that for a new motor, it looks sorta rough already. Weve all been there trying to get a motor mounted that just wont go. Sometimes it works to just lay the tools down for awhile, do something else, then go back after you calm down. Generally whatever the problem was, it will fall into place, and we're left wondering why we had so much trouble in the 1st place. Aint this FUN!! HAHA.

You mentioned having only running the motor a couple minutes, but I would recommend that you remove the oversize pinion and fire up the motor to be sure the motor shaft is running straight. Its possible that the shaft may have bent if it got REAL hot and had a lot of side pressure from the lopsided pinion. Not likely, but possible.

If youre not familiar with how to set the maingear and pinion mesh, its easy. Simply put...you need a tiny bit of space between the pinion teeth and maingear teeth. They don't want to be touching each other. Some guys use a strip of paper and roll it between the gears before final tightening of the motor in place. Lots of info around about how to do that. Onward and upward brother.

[foekie01]

Its possible that the shaft may have bent if it got REAL hot and had a lot of side pressure from the lopsided pinion. Not likely, but possible.

Checked. It is ok.

Had a look on the web and saw a couple of individuals running scorpion motors with 12 degrees timing. They say it runs super smooth on 12 degrees. Knowing this I went to my local hobby store and told the salesman what my problem was and what you guys told me in regards to the timing and what I found on the web.

He told me that people at the flight club fly 450's with the exact same scorpion motor, running on hobbywing 60A esc's. We had a look regarding the timing and the hobbywing esc's do not allow 5 degrees and the closest timing to 12 is 11.25 degrees. In regards to that he could not help me out, so we agreed on me testing things out.

What I have found out is that the motor seems to run fine on every timing setting above 3.75 degrees. Did not check 3.75 degrees because it is below spec. I tried the 11.25 degrees and the motor runs smooth.

What I did notice, and I believe this is a motor problem, is that the motor starts to vibrate and makes a different noise at around 60% throttle. I made a video but you cannot hear it, but you can see the camera shake a little in my hand. below around 60 % and above around 60% everything is fine. Might have to check with the store where I bought the motor. If you like I can post it, but it seems offtopic.

I also finally did receive the correct pinion today and went and mounted it straight away. It is a nice firm fit. Much better than the other one.

So. Next step was mounting everything and making a test flight to check the heat. The good news is that the excessive heat is gone. Both the motor and the esc get only just a little warm after 4 minutes flight with a lot of throttle pumps (normal mode, not idle).

Also, I cannot hear any difference in sound regarding the motor. Maybe the motor has a little play under no load or maybe it even got damaged because of the heat?

Anyway. It looks like I can get up in the air again. Can't wait to see what this motor does under idle mode

Thanks for all the help so far

If anyone has a suggestion or tips, please let me know via pm or reply!

[sconel]

Seems like I'm following your posts but not so...it does seem like we meet pretty often lately tho.

Anyway, the pinion and overheating problem seems solved. What youre calling motor noise and sound at 60% throttle may indicate a damaged bearing in the motor.....OR.....it could be nothing at all. I don't like the sound of it "shaking the camera". Vibrations aren't good.

Right now, the esc timing should be a low priority for you. Timing makes very little actual difference in performance, until you get the heli flying smoothy and perfectly. Looking over your esc chart, I'd just start with default timing and pwm, then maybe experiment after you are familiar with the recommended and default settings You still have plenty of tweaking that's a lot more important. Things that will make a bigger difference in your helis performance. Concentrating on Headspeed, Throttle Curve, Gov Mode are some areas that will make the most difference right now, but 1st of all its gotta fly pretty well.

[foekie01]

Had 3 flights today with idle 1 and everything went well. Motor only gets slightly warm and the esc does not even get warm at all, it is all cool. Man this motor has some power!

Yeah gov and all is for later. Comllicated enough for now

So. Problem seems solved with 11.25 at 8khz timing.

Thanks again!