Epoxy filler on stainless steel.

Discussion in 'Materials' started by gtflash, Jul 10, 2016.

  1. gtflash
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    gtflash Senior Member

    I have had some stainless seat bases made. I intend to paint them. There are a few defects on them, so I was wondering if an epoxy blend will stick to stainless. I would use it to blend the corner welds and fair a couple of light dents. Is this possible?

    Thanks gt
     
  2. gonzo
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    gonzo Senior Member

    Yes, epoxy will adhere to stainless. Make sure you degrease it and scratch it with sandpaper first.
     
  3. PAR
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    PAR Yacht Designer/Builder

    Degrease as Gonzo suggests, but also heavily sand the surface to remove oxidation. To fill welds and minor dings, use a fairing compound, either pre-mixed or a light weight home brew. A neat topcoat of epoxy over the fairing compound will seal it down for paint prep.
     
  4. SukiSolo
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    SukiSolo Senior Member

    As / \ personally I'd degrease with acetone before and after wet and dry cutting with any deburring or angle grinding prior to that. Then try and make sure you don't touch the surface by hand before applying paint. The natural grease on your fingers can become a barrier, worst with aluminim where you need to abrade the adhesive into the clean surface. Fortunately S/S does not oxidise so fast.

    Might be worth grit blasting the corner welds if they are very rough.
     
  5. gtflash
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    gtflash Senior Member

    Thank you all for replies. I have done some grinding and sanding. Ideally I'd leave it stainless and polish but the finish isn't great. I paid peanuts for the welding so can't complain. I presume there isn't a filler that polishes up like stainless? If not I'll skim and paint.

    Thanks gt
     
  6. PAR
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    PAR Yacht Designer/Builder

    Actually, there is a brazing product with a high silver content that will fill the welds, dings and divots, that can be buffed up too. Try this link:

    http://muggyweld.com/stainless
     
  7. gtflash
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    gtflash Senior Member

    Thank you. I've slapped some epoxy home brew on and will paint. The muggy weld stuff looks good, but wrong side of pond for my timescales.
     
  8. mydauphin
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    mydauphin Senior Member

    Will epoxy adhere to stainless absolutely and with all the special prepping it will be OK. But the slightest scratch you are toast. SS without oxygen will corrode if some part is exposed to salt water. Also be careful of brazing rod that might have dissimilar metals.
     
  9. gtflash
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    gtflash Senior Member

    Apologies. Can you explain? I don't fully understand.

    Gt
     
  10. PAR
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    PAR Yacht Designer/Builder

    Stainless requires free oxygen to be present to form a protective oxide on it. Though oxygen is present in water, it's not free (captured by the hydrogen), so it will rust. The alloy employed can have a huge impact on how quickly this will occur (corrosion).

    In my experience epoxy coated fasteners don't corrode, if they're fully encapsulated in goo. They are denied oxygen, but they are also denied moisture, so no corrosion. This said, any breaches in the coating, will cause a path for moisture to get in and corrosion begins.
     

  11. mydauphin
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    mydauphin Senior Member

    Par said it very well, crevice corrosion is the killer, those little unknown pockets that somehow happen, and your SS starts looking like swiss cheese. IMHO leave SS unpainted. if you have some gaps, migs weld some new stainless, same kind, and grind.
     
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