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Media Blast or Chemical Pretreatment Better for Powder Coating?

I am looking to start up a small powder coating job shop. My question pertains to systems I have had quoted. Which pretreatment system has the broadest appeal and why? One system has a media blast system and the other has a chemical pretreatment system.

Tom Drake
- Charlotte, North Carolina
2001

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The answer to your question depends on a number of factors. However the main thing you will have to take into consideration is what kind of substrate you will be coating. If you are starting up a job shop and do not know this I would recommend the chemical pretreatment. A media blast system may be too aggressive for certain substrates and some systems can ingrain foreign objects (grease, oil) into the substrate rather than clean it. However there are a number of chemical pretreatments and you will have to look into the type of chemical treatment more carefully.

I'm sorry I could not give you a definite answer but I would require more information on your circumstances.

Drew Devlin
- North Lincolnshire
2001

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I feel the pretreatment chemical wash is the best way to go. If you will be doing a lot of different parts the media blast could hurt certain surfaces.

Good Luck! Sincerely,

Cliff Shephard
- Charlotte, North Carolina
2001

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Hi, Tom. Drew is right that we need to know what material you want to powder coat, but I think Cliff is right that chemical pretreatment is better because almost any metal you powder coat will require either a phosphate or a chromate conversion coating pretreatment for proper corrosion resistance. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
May 18, 2010