2k Paint guru required

  1. truckdoctor

    truckdoctor Member

    Messages:
    137
    dorset
    OK, shoot me down if you like but I am rolling 2k onto my bodywork. The epoxy primer went on lovely , nice and smooth and thick, however months later . Using the same make paint 2K semi gloss rolled on, all is well, nice and smooth until just as it is hardening off tiny bubbles appear ruining the finish. I am mixing with the correct quantities etc. but using an aluminium stirrer in the electric drill . I'm sure i read years ago I think that this is not a good idea as it causes some kind of reaction? though I can't find the reference any more. Any ideas please?
     
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  2. brightspark

    brightspark Member

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    28,884
    Location:
    yarm
    may be silicone contamination that's causing the pin holes
     
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  3. Burdekin

    Burdekin Chief Bodger

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    No expert but looks like solvent pop to me.
     
  4. carbon

    carbon Member

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    1,412
    Location:
    S. Glos. U.K
    What sort of roller did you use? Did you have a lot of bubbles when you mixed it with the drill.
     
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  5. Slowcoach Member

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    237
    Location:
    Bedford
    Looks like solvent pop to me. Usually caused by not leaving enough time between coats, or possibly rolling a heavy coat on.
     
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  6. truckdoctor

    truckdoctor Member

    Messages:
    137
    dorset
    Didn't notice any bubbles when mixing but did roll on three heavy coats when just "tacky" in between. I tried 3 different rollers , high density foam and lambs wool type, the later being the better as it held more paint and better coverage. Is there no issue with the ally stirrer then ?
    Will try again tomorrow , I'm wondering if the temperature of the panel is an issue as it was in the sun before painting
     
  7. carbon

    carbon Member

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    S. Glos. U.K
    I haven't heard of an issue with aluminium as most measuring/mixing sticks are aluminium. Did you add any thinners?
     
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  8. truckdoctor

    truckdoctor Member

    Messages:
    137
    dorset
    Paint is lechsys industrial 2k acrylic with Upol 2032 standard hardener. Ratio of 2 parts paint 1 part hardener and 5% universal thinner I tried a foam roller ( not good) and a lambs wool type that holds more paint. I did apply coats when the first was "tacky" , 3 in total. The paint but i was smooth from the roller and then the bubbles appeared after as it was drying. The panel was hot in the sun
     
  9. 123hotchef Member

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    9,015
    Location:
    Kent
    try some rocket in the mix
     
  10. Slowcoach Member

    Messages:
    237
    Location:
    Bedford
    Have you done the whole truck in one go. I’d have thought a roller would put plenty more paint on than a spray gun.
     
  11. carbon

    carbon Member

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    1,412
    Location:
    S. Glos. U.K
    Ive never added thinners when using a roller with 2k paint but have never painted any large areas with a roller. I used a foam roller and didn't notice any bubbles
     
  12. truckdoctor

    truckdoctor Member

    Messages:
    137
    dorset
    Rocket? Like this P1060641.JPG
     
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  13. Slowcoach Member

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    237
    Location:
    Bedford
  14. postie jon Member

    Messages:
    854
    Location:
    Aberdeenshire, Scotland
    i would say too heavy a coat ,solvent coming to the surface as it is curing ,esp with 3 heavy coats.
     
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  15. MetalMonkey Member

    Messages:
    281
    Location:
    UK
    Rocket is an accelerator, i think at this stage I would want to slow everything down to give the solvent a chance to flash off.

    Can't really say I've ever brushed 2K, only sprayed it but I would start off by using more thinners and try much lighter coats - you will need to try and build it up in stages.
    How long did you leave your primer to go off? I've also seen this where the primer has still been off gassing.

    Unfortunately I suspect you will find you will have to sand it right back to primer to get rid of the pock marks.
     
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  16. malcolm

    malcolm & Clementine the Cat

    Messages:
    9,026
    Location:
    Bedford UK
    I had solvent popping like that spraying celly in the sun. Don't do it in the sun! Painting too thick and wet on wet won't help either - thinner coats with plenty time to dry are best to avoid that.
     
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  17. steveo3002 Member

    Messages:
    5,223
    cambridge uk
    looks like solvent pop to me , would not use rocket

    and no need to stir it with a drill , just a gentle mix with a ruler is enough
     
    Last edited: May 9, 2020
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  18. truckdoctor

    truckdoctor Member

    Messages:
    137
    dorset
    Today i sanded off most of it and mixed a small amount using 20% thinner. Applied sparingly with a sponge roller and things were full of bubbles so switched to a microfibre type and thing were better but still bubbles . I then rolled over the bubbles with a dry sponge type roller and that smoothed things out to the point of being acceptable for me. I'm not looking for a gloss smooth finish , more of an industrial look. Temperature is very warm just now I dont think this helps too much. Going to try again when the temperature gets cooler. Thank you all for your tips and tricks.
     
  19. 123hotchef Member

    Messages:
    9,015
    Location:
    Kent
    have you tried without any thinners?
     
  20. steveo3002 Member

    Messages:
    5,223
    cambridge uk
    slow hardner might help if u need to buy more
     
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