Thank's a LOT Pcmoor. This a great help for me. I feel more "normal" and not so alone... I will take method 2. So if I understood well, I must rebuilt everything... No "magic" trick to eliminate old scaling of groups, and let the geometry like it appears without this "memory". Groups keep "memory" although one make them unique...!
As there is no mirror copy, the only way i found is to apply a scale -1 in X or Y axe.
In my project, i have a lot of components that are symmetricals and I've build all my models using this scale -1, without knowing this little "detail"...
Last, When you say groups "CAN" retain, and "scaling can easily become out of sync", is it unpredictable? or is there any ley, here? Sorry to insist, but i really like to understand and avoid future problems!!!
Really very grateful for your support and help.
Xtian
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