aluminium - degrease, sand with BOLL abrasive cloth, blow off and degrease again with "BOLL silicone remover", then apply the next coat. BOLL POLYESTER RESIN 1Kg + Hardener. steel - degrease, grind with P80-P120, blow off and degrease again with "BOLL silicone remover", then apply another coat.
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