Additional sealing on the skin?

[Omar Mir]

Hi, so I did two coats of Tremclad:

https://www.homedepot.ca/en/home/p.rust-paint---green-378l.1000406105.html

 

And it seems the paint comes off pretty easily - am I doing something wrong? That is 24 hours after application. Am I just not waiting long enough - seems pretty dry till I handle it roughly a bit? Or did I miss a part where I need to use another sealer?

[even-keeled]

What cloth was used on this boat?

[Omar Mir]

The premium fabric from the store.

[Hirilonde]

"TREMCLAD Rust Paint provides superior rust inhibition, and is specially formulated to penetrate rust and bind to metal. Excellent rust coverage - designed for direct application to metal; primer not required on most applications"  -from the link-

[Omar Mir]

Yep the container mentions wood and "most surfaces" - I also checked online and found a bit here:

http://kayakforum.com/cgi-bin/Building/index.cgi/md/read/id/213629/sbj/skin-on-frame-finding-a-skin-and-sealant/

 

I've left the canoe outside today. And will be gone a few days. Maybe the sun and some ventilation will help. The first coat seemed to grab on strong.

[Kudzu]

Not familiar with Tremoclad but assuming it is similar to what we have here in the States, I would say you just didn't give it enough time. Rustoleum oil based paint is my  first choice because it is so tough. Oil based takes several days to fully dry and harden. If I can I put mine out in the sun as much as possible and I don't like to use one for a week.

 

So while there is now way to know for sure, I just suspect it isn't fully cured.

[Omar Mir]

That's what I suspected - thanks - was going nuts here. It is in fact rustoleum brand oil based paint.

 

This part sucks. The waiting I mean.

[Omar Mir]

6 hours ago, Kudzu said:

Not familiar with Tremoclad but assuming it is similar to what we have here in the States, I would say you just didn't give it enough time. Rustoleum oil based paint is my  first choice because it is so tough. Oil based takes several days to fully dry and harden. If I can I put mine out in the sun as much as possible and I don't like to use one for a week.

 

So while there is now way to know for sure, I just suspect it isn't fully cured.

 

Do you take it in if its going to rain? I can leave it out but Im gone for a week and its supposed to rain in between.

[Kudzu]

It SHOULD be dry enough that rain isn't going to affect it. Either way it should dry in a week.

[Omar Mir]

Still not great, I think I lathered on the paint too thick and between the humidity here and the rain it hasn't dried yet. This first boat has been a great learning experience - I might try building this same boat again if I ever get to try this on the water and like it (I love the look of the boat so much!). I'll give it another week outside to see if it cures. It seems to have cured more in the week but doesn't seem to be done. 

 

If it doesn't dry I'll see if I can scrape it off and try with a different water based paint and then use Minwax Water Based Helmsman Spar Urethane to seal it once dried.

 

So I guess my question is: Should I give it another week because of weather/my own incompetence in using too much paint OR should I just scrape it off now and start with a new paint/Urethane?

 

I really don't want to reskin right now if I've ruined the skin but if that's required also would like to know.

[mitchmellow]

You mentioned 2 coats.  Was the first coat thinned?  Allow enough drying time between coats?  I used Rustoleum on the only boat I've built.  Adhesion was not a problem.  I applied 3 coats with the first thinned.  I did use different polyester cloth.  Your picture makes me think you did not get good adhesion with the first coat.

[Omar Mir]

So I did thin the first one (and actually the colour you see from the scrape is not the cloth colour BUT the colour of the first coat).

 

Coat 1: 85% Paint and 15% Thinner - Dry time before next coat: 24hrs - SAND COLOUR (notice the scraped bit is all green and no sand).

Coat 2: 100% Green Tremclad (Rustoleum brand). Dry time before next coat: 24 hours. Not thinned.

Coat 3: 100% Green Tremclad. Drying now for 7 days. Not thinned.

[Hirilonde]

There are 2 ways to get one coat of paint to stick to another well.  One is to do the second coat as soon as the first has just barely dried to the touch.  With oil based paints that is several hours or so depending on temperature and humidity. This leads to a chemical bond between coats.  The other is to let the first coat dry/cure completely through and sand the surface to provide for a mechanical bond.  Because the cloth is textured sanding is less necessary for the mechanical bond, but if a couple days lapsed I would light sand first.  I painted all my boats with oil based porch and deck enamel and did 3 coats with hot recoating over about 24 hours.  Then let it all cure for a week before real use. (I cheated to see if they floated)

[Omar Mir]

I essentially did the oil paint as you noted with 24 hours in between. I think I made the error of putting it on too thick. Far too thick. And now.the curing process is taking a much longer time.

 

Do you think there is something I can use to seal the paint? Or should I let it sit (not sure how long it might take).

[Hirilonde]

Too thick would lead to the results you have encountered.  I can't tell from here, but a likely conclusion.  There really is nothing you can do to speed up the cure.  Yeah, time will work, but no guesses as to how much.

Hot recoat with 2 part paints can be done almost indefinitely.  The paint cures chemically without having to gas off like 1 part paints  1 part paints can be hot recoated, but I would not do more than 3 coats total before allowing a full cure.

[Omar Mir]

So i've already done 3 coats as noted above, so I should really just wait eh? I assume its a bad idea to put on some Spar Urethane to seal the whole thing? Or any of the following:

https://www.homedepot.ca/en/home/p.epoxyshield-anti-slip---clear-340g.1000785172.html (epoxy shield)

https://www.homedepot.ca/en/home/p.lacquer-clear-312g-aerosol.1000120299.html (lacquer)

[Hirilonde]

Every layer you add slows down the cure of the first 3 coats that are already not curing properly.  You would be putting a skin over it, it would still be soft.

 

I don't know of any short cuts for curing.

[Omar Mir]

That's fair. Just needed to hear that! I promise to post pictures soon. Thanks so much for the advice. This forum is just wonderful.

 

 Already planning the castaway and with all the lessons learned the hard way (and there were many) I think it's going to go wonderfully .... he says tempting karma. I might even not have a million questions!