the 3D prints are at 0.5mm but the injection moulds are hitting 1-2mm. the challenge is frictions between abs and metal locks. There's also the balance between precision and cost. I'm trying out torx screws. Flat heads seems to increase wear and tear on abs. I'm also trying out rubber adhesive gap fillers. I'd reckon someday advanced additive manufacturing might eventually help out minimize inventories, reduce error and high import cost but pipeline dream.