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Removing Saltwater Rust from Cast Iron to Epoxy Prime?

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Removing Saltwater Rust from Cast Iron to Epoxy Prime?

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Old 04-15-2018, 09:53 AM
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Question Removing Saltwater Rust from Cast Iron to Epoxy Prime?

I have 2 Velvet drives that were Saltwater used ,I had them sandblasted . The rust came back with in a day! I want to Epoxy Prime and Paint , but
dont want the primer lifting in a years time , I would use a self etch or rust converter , but the primer ( Southern Poly ) says not too use over either. .
Directions say that it will handle some flash rust , but this is some agressive rust . I think the tranys were submergered. Any suggestions?
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Old 04-15-2018, 10:57 AM
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curious to read the answer! I'm surprised to read rust comes back within a day after sandblast! Geeez I never thought salt was that much aggressive and corrosive!
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Old 04-15-2018, 11:54 AM
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cast iron is often porus, and sand blasting does not remove the contaminates except on the surface. Washing the housings (soak if you can) with soap/water or Beter yet acetone/alcohol and baking in a oven to evaporate whatever is in the iron will help a bunch. Sometimes it takes several rounds of cleaning, and other times it never really cleans up if it it's really bad.


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Old 04-15-2018, 01:20 PM
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I was shocked as hell when the rust came back !
Im going to try Evapo Rust , Ive used it before but not on cast and not under paint ,
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Old 04-15-2018, 05:40 PM
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I've always used a rust remover with phosphoric acid (Evaporust maybe a brand name product with phosphoric acid). It's a great rust remover before paint application, the rust removal process results in the formation of iron phosphate which is more stable than iron oxide (rust).
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Old 04-15-2018, 05:49 PM
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after removing rust dry it and coat it with diamond clear by KBS . about ready to use some evaporust to clean out the water passages in a couple set of heads. dont think it works well on aluminum it can be brush, rollered, sprayed. it can be used as a sealer under coat and a very glossy over coat. have used it for both sticks better than glue handles tems in the 450 range.
KBS : STOP RUST : PREVENT RUST : RUSTY METAL PAINT :: PAINT RUST

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Old 05-21-2018, 07:29 AM
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Originally Posted by dunnitagain View Post
I was shocked as hell when the rust came back !
Im going to try Evapo Rust , Ive used it before but not on cast and not under paint ,
Did this work for you? Looking for same kind of solution.
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Old 05-28-2018, 04:57 PM
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The evaporust works very good , it has been unpainted since I started this thread and it still has not returned.
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