I assume you mean to actually add/remove/alter the material zones, oppose to changing colrs etc. Yes you use an app, like UV mapper, that can reassign materials to polygons. In UVmapper. 1)Open the obj 2)Select>Mataerial> you chose 3)Assign>Material> You chose 4)Save To make new materials on various polygons 1)Open the obj 2)Exportuv's>Save out Uv's for later 3)Select Poly's/remap/do whatever you have to to get the polys you want on your custom material into one area 4)Assign>Material> You chose 5)Unselect 6)ImportUV> Apply Uv's you saved out to restore the mapping 7)Save Obj may be fragmented which can cause issues with firefly Use SPanki's free STOMP utility (See PIC) 1)Open obj 2)Save out OBJ 3)Unselect mtl checkbox 4)Select "By Materials" 5)Save Hope that helps. Anton

-Anton, creator of Apollo Maximus
"Conviction without truth is denial; Denial in the face of truth is concealment."

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