base over cured SPI epoxy

Discussion in 'Body Restoration' started by TX79Z28, Jul 1, 2013.

  1. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    I have read many threads, as well as visited the SPI website and forum, and I am getting somewhat conflicting messages.

    I have the car in SPI epoxy (black) and plan on shooting slick sand, and 2K this week. Sometime before assembly, I want to shoot BC/CC over the "hidden" areas (cowl, tail light panel, etc). The epoxy will be WELL past the 7 day re-coat window. I have read of two methods:

    1. scuff cured epoxy with a red scuff pad, shoot thinned down epoxy (sealer) and then the BC/CC

    2. scuff cured epoxy as above, and shoot non-thinned coat of epoxy, BC/CC

    Which way is better? Is it just a matter of personal preference?
     
  2. spicewood1

    spicewood1 BANNED

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    Why not lightly scuff the cured epoxy and go ahead with the color? That 7 day window is for topcoating without scuffing. After a week you HAVE to scuff. Call Barry.
     
  3. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    I have read of adhesion issues with just scuffing after its cured/after 7 day window. I guess just wanted to know if it was super important as to it was sprayed with full 1:1 epoxy, or a thinned out sealer version of it
     
  4. stevenp3762

    stevenp3762 BANNED

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    doesn't matter, it will just flow alittle better thinned.
     
  5. spicewood1

    spicewood1 BANNED

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    Barry will answer all your questions. You will not have adhesion issues with scuffing - quite the opposite. I would not waste time and $ on more eooxy. Just scuff and shoot it w color
     
  6. allstar12316

    allstar12316 Veteran Member

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    You could either shoot straight color, or if you use another coat of epoxy I reccomend you thin it a little. This will help lay the over all job to lay down a little flatter and give more of a mirror like finish
     
  7. Rick WI

    Rick WI Veteran Member

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    The nad thing about over reducing is the extra solvents. If the pressures at the gun are correct normal reduction with the activator will produce a very slick smooth finish.

    Solvents can get trapped under rop coat finishes and cause die back, or worse. A dulling affect. So need to allow extra flash time if you do that between coats.
     
  8. spicewood1

    spicewood1 BANNED

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    I agree. I rarely reduce the epoxy . I am a believer that you want as little undercoats as possible for best long term finish. I have never once used a sealer.
     
  9. Rick WI

    Rick WI Veteran Member

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    Likewise. Unless I need a ground coat on a 3 stage I shoot directly over a prepped solid coat of cured 2k urethane primer.
     
  10. chevylet

    chevylet New Member

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    SPI says to scuff their epoxy if its out of the recoat window then shoot 1 coat reduced. Let sit over nite and follow with your primer. Shoot 2-3 coats urethane or polyester. let it cure for a day or overnite before starting to block.
     

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