How to make a flat spot on a scorpion motor shaft

[coolgabsi]

coolgabsi submitted a new Article:

How To Make A Flat Spot On A Scorpion Motor Shaft

So,


I have noticed some scorpion motors don't come with a flat spot on their shafts. Some do, but some don't. Could be true with any other motor too. So... It's recommended if you are gonna run any kind of pinion or like setup , you should have a flat spot so it won't move around.

Building my whiplash, I came across this shaft , which from stock didn't have a flat spot.. (Scorpion motor shafts of different lengths are used for different birds, align needed 100mm, whiplash needs 6-7 mm smaller)



View attachment 8358


Why??

The motor magnets are extremely strong, any metal shillings / shavings which WILL be produced while making the flat WILL go to the magnets and can and will cause destruction of your expensive power house. So this is to be done to every motor if you wanna do anything on it , even sand something on it, if you want to save the motor from early destruction of itself


Assuming you know where your pinion is sitting and you have marked a spot on the motor shaft to where the flat needs to be ... (This can be done by dry fitting the motor on the heli with the main gear on it, and seeing how you can get full contact (vertically ) with the main gear . And tightening the grub screw on the pinion right (making a mark on the shaft)

Step 1: take apart the motor...

C clip pliers (harbor freight sells these for 5 bucks for set of 5)

View attachment 8359

Remove the wavy washer and keep it aside with the C clip and save it



View attachment 8360


That's all that's holding the motor, so now pull hard on the stator of the motor. It's only held in now by magnets .

View attachment 8361

(So these steps upto here are the same if you need to change scorpion motor bearings, or shaft.... Bearing are just sitting in their cavity on the stator top and bottom. And shaft has two hex nuts and is press fit in the can, so need a drill press for it... To push it out)

View attachment 8362

Back to the topic:

Take a sealable plastic bag, ziplock or something and cut off its corner... A very very small peice...

View attachment 8363


Insert the motor shat through that hole (it should be a tight fit in that hole.

View attachment 8364


Once in , clear the plastic of any work area and "stuff" it in the can so it can collect all metal waste produced. Seal the ziplock bag so nothing comes in of out




View attachment 8365



Then use a diamond fuses cutting wheel on the shaft with a seemed or something and support both the can and the shaft very well, as the metal on the shaft is very hard and dremel will wanna slip around and you don't want that if you want a good clean flat ... Go back and forth and move the shaft just a hair left to right to make a good flat .


View attachment 8366





And whoalla...

View attachment 8367



View attachment 8368


It's not perfectly smooth and pretty cause I got distracted in the middle of the dremelling SQUIRREL!! Lol


Once done take the plastic off carefully so the metal waste is contained, and put the motor back together just following the steps in an opposite fashion.... Stator goes in, carefully aligning with the shaft, then the wavy washer and then c clip and DONE!

Anywaz .. This is simple thing to do, like I said not just when making a spot but anything that'll create metal waste on the motor.. Please take these precautions.

Fly safe!! have fun!

Read more about this article here...