Hi Christophe
Thank You for your compliments.
I don't have any videos or anything setup right now, But how you use the jig is simply rest the armature shaft on the 2 blades, I usually take the bearings off and sit the armature on the blades where the bearings ride, the heavy side will always rotate to the bottom then just add little washers to the top side with some tape, once your happy with the balancing mix up some epoxy and secure them in place, it might take a little time to achieve perfection but then perfection comes with patience

Doug