General Pinion gearing explanation

Stripping gears just means you have JUST the right amount of power in the motor hahahahaha. In all honesty, reading this thread, I will almost bet money that the 22 is going to be the pinion of choice.
 
So the Goblin motor is coming down quite hot. Would going with a bigger pinion make it cooler?
 
hotter......

What head speed are you running?2320

What timing are you using in the ESC?

the PWM setting can be really important in matching it all up. (just learning about all this now)

you should run governor mode to get stable headspeed ... especially if you are getting into 3d

80% flat governed throttle curve.

just ... speeling what I have learned in the last 24 hours.... :)

I am not sure how to set up the Castle..... but I have learned that hot motors are sometimes PWM rate not set up correctly from the research I have been doing anyway.

I heard that Scorpions like 5-8 Khz depending on the ESC.....

from what I have been researching for my new ESC (YGE CLONE ON ITS WAY) Pwm is really important as if you have it too high ... you get lots of heat ... and too low ... they run cool but are inefficient (the Motors)

the calcs I have been looking at say

POLE COUNT (P) x KV (K) x VOLTAGE (V) /(DIVIDED BY) 20

so for eg: my motor BL650L (ALIGN - OLD BUT HEY IT IS WHAT IS IS LOL)

P = 6
KV = 1220
V = 25.2 (6s)

6 x 1220 x 25.2 = 184,464

/ 20 = 9,223.2 Hz

= 9Khz (round down and test) .... cooler option first. Most ESC's with adjustable PWM setup will b 8Khz by default (as far as I have read) Castle may be 5? not sure.
 
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Thanks for the math Westy :D LOL

But I got the motor gearing and governor under control. The PWM has been on 12 khz up til now, but I just set it down to 8 khz - see how that works out. I'm afraid I'll loose flight time because of it?

I'll test fly tomorrow and see how it turns out.
 
Let us all know ... will be an interesting experiment.

What exact ESC are you using? ... i love to research! :)

What motor? the Scorpion 4035-560?
 
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Westy said:
Let us all know ... will be an interesting experiment.

What exact ESC are you using? ... i love to research! :)

What motor? the Scorpion 4035-560?
Click to expand...

I have the Castle Ice2 120 HV and a Turnigy SK3 Helidrive 560 KV (4100W). I'll post the results tomorrow ;)
 
looking at some of the data on the motor ... some guys are saying 8Khz is the setting you need! :)

Try 5 First and check temp ... and power ... then 8 .... Just a suggestion

I am sure we will all find out by morning.
 
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Just got in after testing with 8 Khz on the PWM setting - no change. The motor is still hot and the flight time remains the same. I read that going with a larger pinion usually ends in even hotter motor. So I think I'm going to get a hold of the 22T for my Goblin - then set the HS to 2200~2250 (it's pretty crazy at 2300 anyways LOL).

I also read that the motor heat and ESC heat varies depending on what ESC brand one's using. Castle (which I have) is known for heated motors and ESC units.
 
Have you put a temp gun on the motor can? If so, what is the actual temp of the motor? Gaba says his Scorpions always come down hot.
 
Tony, that's just Gaba bragging. :)

Marius, I haven't setup castle esc gov yet, but is there a gain setting? I believe I've read that too high a gain setting on gov can result in overheating too. The gov ends up doing the same thing as tail wag, but with revs. This leads to unnecessary pulses of throttle to do the upswings and thus inefficiency and higher heat.

Also, is the ESC getting hot, or just the motor?
 
Tony said:
Have you put a temp gun on the motor can? If so, what is the actual temp of the motor? Gaba says his Scorpions always come down hot.
Click to expand...

I'm not sure how hot the motor can be and remain within tolerance, but it's so hot you burn your fingers! I do not have a temp gun, but I'm sure I can borrow one from somebody.

pvolcko said:
Tony, that's just Gaba bragging. :)

Marius, I haven't setup castle esc gov yet, but is there a gain setting? I believe I've read that too high a gain setting on gov can result in overheating too. The gov ends up doing the same thing as tail wag, but with revs. This leads to unnecessary pulses of throttle to do the upswings and thus inefficiency and higher heat.

Also, is the ESC getting hot, or just the motor?
Click to expand...

Yes, the gain is set to 18 on a scale from 0 - 35. The motor seems to work good on this gain, but I haven't tried any lower. I can try it and see what happens.

_____

I also noticed the series Y-cable gets hot. The leads on that thing looks to be a bit on the thin side - at least when compared to the battery leads. Can poor wire gauge cause motor heat?
 
What awg wire and size/type connectors are you using? Undersized wiring and connectors could be leading to higher resistive load on the power system, which will result in wires and connectors heating up, but I'm not sure that would result in motor heating. I'd expect it to end at the ESC. However, I suppose it could be leading to phasing issues which could lead to motor inefficiency.

You don't have any extensions on the ESC->motor connections, right?

Do you have a near short in the motor? Maybe it is drawing a lot more current than expected? Maybe try the testing in the vid that Westy posted?

VIDEO: BURNING UP ESC's ? - Wath this before blaming the ESC - IMPORTANT
 
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I'm not familiar with the AWG size system, but let's just say that if the battery leads are AWG 100 - then the leads in my Y-harness is AWG 50... Even if the Y-harness is not the culprit, I think I'm gonna make my own Y-harness with much thicker leads. I'm no electrics wiz, but I know that wires are not supposed to be hot.
 
I haven't read this is detail.. But , if your motor is coming down very hot, change pwm to 8khz and itll be better


My motor even the hkiii comes down very very hot

Fly safe!! :) have fun!
 
Definitely upgrade the Y harness, then. It may not be your problem, but it will not hurt and it should reduce resistance up to the ESC input which will result in less voltage ripple, a bit more efficiency and less strain on the ESC and batteries.

AWG is the abbreviation for gauge measurements. I'm sure it makes sense if you know what it stands for, but how they got wire gauge to shorten down to AWG, I don't know. :)

Most 6S 5000mAh packs I've seen have 10gauge wire leads on them. I'd recommend no less than that for your y harness too. 10 gauge is about the most you can fit into a 5mm bullet connector (such as used on EC5 connectors) without having to trim down some strands.
 
Stands for American Wire Gauge. As the number goes up the wire gets smaller. This is because in the olden times you started with 0 gauge wire then pulled it through a die to shrink it. Number of dies you had to pull it through was the gauge. 10 gauge wire had been pulled through 10 decreasing die sizes. 0 gauge wire is about 1/2 inch in diameter or 52mm. 10 gauge is 5mm and 20 gauge is .5mm. Welcome to American measurement systems. If you think this is bad try to measure a friggin liquid.

Also, before you think I am really that smart, 1/3 of that info comes outta my head, the other 2/3 was off wiki.
 
Does your ESC have temp logging ?

remember as soon as you stop the motor .... all the heat is released from the copper ... so it will get a lot hotter than in flight.

Can you try 5Khz and see what happens? see if you have a power loss or time increase.
 
I checked the temp sensor before I changed any of the ESC set up, it showed a max temp of 80°C, which is quite warm! Then I made a new Y-harness with thicker leads - after this it could show a max temp of 60°C - so looks like the new harness helped on ESC temp. The motor was unaffected by this however - still hot as the sun.

I then lowered the headspeed to 2200, and also lowered the gov gain to 17 (from 18). The Goblin became more docile, but still very 3D capable. The governor seemed to work just fine on the new gain. But when the flight was finished, motor still hot as the sun.

I like the new headspeed, so I'll stick with it.

But the question is: Should I get the 22T pinion? Or can the motor live with this heat...?
 
can you try lowering the PWM to 5

see what happens......

any other timing settings in the castle software?

I have heard though that the Scorpions run rather hot.... good flight times?

If your wiring is not hot then that is a good sign to start with.
 
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