Gain from brushless motor sensor alignment
 

I am wondering what is the gain from having a sensor board that is within +/- 1 deg from each other vs say 3-4 deg. In theory there is gain to be had, does anyone has actual experience say from dyno chart to actually prove the point?

The cheap motor analysers are relatively accurate (say within 1 deg consistently), have anyone else try to align bad sensor board to gain performance?

what?

who are the each other?

I believe he's referring to the (3) sensors on the board.

The hall effect sensors? I don't think you can change their relationship to each other.

Sure you can, you resolder them on the board.

Resolder them 10 degrees advanced

http://www.euronet.nl/users/tooms/ftp/sensor.jpg

Don't they still have to be in near perfect 120 degree steps?

Wouldn't this be cheating? Most rules limit you from turning past the timing marks correct?

On a side note, I stand corrected. The things people come up with are insane.

Yes, when they are perfectly 120 degrees from each other placed the rotating field should work the most constant what does give a colder motor and maybe some higher rpm.

If this is cheating.... isn't re-shimming the rotor for a better timing or calibrating the sensors by re-soldering the same? This was just a test on an old speed passion motor, I went from 420 rounds per seccond to 460, that is 2400rpm more....
I have shown the pic to the guys who do open motors to see if they are legal, they could not see anything wrong on the picture....

Thanks I was referring to the 3 Hall effect sensors. With most motors their sensors are out of symmetry ie not perfectly 120 degree apart, some more and some less. I have seen motors from reputable manufacturers where their sensors are out by 10 degrees i.e. one is at say 30, second 20 and third is 26. I have ‘realigned’ sensors by trial and error where I unsolder the sensors and advance or retard their position. In the above situation I may retard the timing of the first sensor and advance the second. I have killed a few Hall effect sensors during the process, they either stop working because of the heat or those tiny legs break off.

As I don’t have a motor dyno it is difficult to tell if aligning the sensors actually improve the actual performance, interested to see if there is actual gain.

When you refer to re-shimming the rotor, your talking about the centering shims at the front and back to keep the rotor between the magnetic field?
I just want to be on the same page, because I've never heard of re-shimming a rotor to alter the timing.


Well you could argue that picture is a defect in manufacturing, all of the sensors line up slightly off the printed marks. Intentionally altering the sensors to give a slight advantage and keeping it hidden is by definition cheating.

on a side note: your not calibrating anything, your intentionally re-positioning the sensors to gain an advantage, dont try to take some kind of moral high ground by calling it calibrating.

all the get arounds in this ..(reshimming- altering senor location ) is why old and your drivers are going away from this hobby..sure in the ole brushed days we had a tool to slide thru brush slot to turn end bell in hand out races.. traxxas has still brought more to this hobby and ur get arounds have chased many more away..

What I am referring to is to optimise the motor, currently you can pay more for a ‘premium’ motor that the tolerance is tighter, if you do not want to or is not able to afford a premium motor or you simply got a dud this is a work around.

the optimized motors are just shimmed motors some might have been put on a magnetize to make stator mags stronger not moving the sensors to a cheating position.

I agree that altering the motor timing in a fixed timing motor is cheating. But if the timing is adjustable and the mechanical limits of the timing cover prevent you from timing your motor how yow want, have at it. As far as the timing alignment goes I've been told that +/-1° is great and those boards are found in your certified/custom/select motors. But I think if your seeing a 5° spread on a skyRC/ebay type motor tester its probably close enough. Close enough to win races anyway. if you really want to get nuts you can find a motolyser and time it much more accurately.

Thanks for the feedback, I am wondering if anyone has compared a Motolyser and the more generic offering such as SkyRC? When I use the SkyRC analyser the result is consistent, at most it is +/- 1 deg for repeated test on the same motor in term of timing.