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Paint renewal

Discussion in 'Tips and Tricks' started by MikeCav, Aug 20, 2009.

  1. MikeCav

    MikeCav Restorer/Videographer

    I had to leave my '29 OT in the sun for about 3 months last year - the paint (Kirby's Bottle Green) oxidized horribly. I called Kirby's for any suggestions. They said to wipe it down with Penetol.

    I did it this morning and it looks great (so far!) Anyone else tried this?
     
  2. Max Peterson

    Max Peterson LOVES Wooden Canoes

    Mike,

    This is also an excellent way to renew faded gel coat on a fiberglass or composite canoe. I recently did the deck of a badly weathered old Sunfish and was amazed at how good it looked. After cleaning your gel coated boat with Penetrol, put on a coat of 303 for UV protection. I don't know how 303 would act on traditional paint, and I'm not going to be the first to try it on a valuable boat.

    Max
     
  3. OP
    OP
    MikeCav

    MikeCav Restorer/Videographer

    I've used 303 on "tupperware" Kayaks and it does a good job. I would not use it on paint since it has silicone which will really screw up your next paint job.

    Update - the Penetrol dried well on the the Kirbys paint - looks like a new paint job (without the runs and bugs!)
     
  4. Rob Stevens

    Rob Stevens Wooden Canoes are in the Blood

    What exactly is Penetrol, and how does it work? -dissolve a thin layer of paint/gelcoat?
     
  5. OP
    OP
    MikeCav

    MikeCav Restorer/Videographer

  6. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Penetrol is a mixture of solvents (naptha, stoddard, mineral spirits) some linseed oil and some soya alkyd resin. When your paint gets dull, it's because the paint's surface has oxidized. By rubbing it down with Penetrol, you are essentially oiling that thin film of oxidized paint. It has a similar effect to oiling a piece of wood - the color darkens a little, the grain becomes clearer and you add a bit of shine to it if it's smooth enough. Same deal here, except the re-oiling is helping return the oxidized paint surface to a look more like it had when it was new and not oxidized. I imagine that the Penetrol actually soaks into the paint a bit, feeding it fresh oil and making it a teatment that's more than just sitting on the surface, but I have no idea how deep it goes.

    The other option is always using polishing compound to do a similar task, but in a different manner. Compounding and buffing actually removes the oxidized portion, exposing non-deteriorated paint below it and buffs a shine onto it's surface in the process. You lose a bit of paint thickness when buffing, but probably end up with more shine (if that's what you're after). The Penetrol finish may look just as good or better on lower-gloss paint, like Kirby's, though it's a cosmetic fix, not a structural one. The oxidized paint is still there (unless it rubbed off on the rag) and it looks better, but it's still a thin layer of dead paint. The Penetrol does not polymerize and re-solidify the damaged surface the way certain polymerizing oils do on wood (like gun stocks with a smooth hard surface). The Penetrol treatment will last as long as it lasts, depending on weather and sun exposure. If it starts getting dull again, give it another coat.

    You may even want to adopt some sort of system where you apply Penetrol for a couple of seasons and then use something like 3M 'One Step" cleaner wax every third season to buff off the oxidation (which really isn't doing much good) and start over.

    I'm not sure that 303 contains silicone (the msds doesn't say). In their FAQ section they do say to use it instead of products that contain silicone to avoid paint fisheye problems later, which would tend to indicate that maybe it is silicone-free. In any case, it's one of the best wipe-on UV filters that you can buy, so it might be worth a phone call to them to find out if it's suitable for finishes that may eventually get repainted.
     
  7. OP
    OP
    MikeCav

    MikeCav Restorer/Videographer

    Thanks, Todd. I think you are right - not too much oxidation came off on the rag - even though I rubbed a test spot fairly hard. So I think what you get is shiny dull paint! But it looks good and was easy (20 min.)! The Kirby's folks recommended this approach.

    Thought about polishing compound, but my boat has some lumps & bumps so I was afraid that high spots may wear through the paint.
     
  8. Todd Bradshaw

    Todd Bradshaw Sailmaker

    You would have to work awfully hard with polishing compound and a buffing cloth to wear through sound paint because it's probably up in the 15,000 grit range or higher (the finest sandpaper I have is 12,000 grit and polishing compound is the next step up the ladder from it). If, however, the paint is really oxidized badly, you can cut through it.

    We had an old Hobie Cat that we painted the decks of with Brightside and then left it out on the beach 24/7 for about six years. It was getting really dull-looking, so we went at it with One Step cleaner/wax. It did an amazing job of shining the paint back up and getting the oxidized paint off, but there were some thin spots when we were done. Im sure the paint was much thicker originally, so all I could figure was that the oxidizing went really deep in places and the polish took off everything that wasn't in good condition. I guess it makes sense that oxidized paint particles would have lost some of their mechanical abilities and hardness and can be buffed off without putting up much of a fight.
     
  9. meeced

    meeced Curious about Wooden Canoes

    I just got a wood canvas OT Otca 1963. Old town suggested to use any marine paint and said they use Pettit brand. Any suggestions? or just get some marine paint?
    Don
     
  10. martin ferwerda

    martin ferwerda LOVES Wooden Canoes

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