what do you apply first paint or sealent?

[st4tic]

what do you apply first paint or sealent?

the sealent i am using is spar urethane but it says make sure the wood is free of foreign matter, so paint first or not?

[RandyStacyE]

What material are you using?

It makes a difference, but in most cases (if not all) it means 'apply to the original surface and the original surface ONLY'.

I know that with most 'high performance coatings' you want to apply it to the original substrate for best adhesion to the substrate because coating manufacturers do not claim to bond to paints necessarily ... but to the wood. You can't expect a high performance coating to bond to the wood if paint is there to begin with.

Assuming that this is a high performance coating. If it were junk to begin with ... it wouldn't matter. That is why I ask what you intend to apply.

[st4tic]

well im applying it to pine with primer on, but does the moisture from the tank on the paint release toxins or not? because im using a spray paint to paint the outsaide of the canopy i was just worried the paint being damaged.

[RandyStacyE]

Sorry ... I just realized you mentioned it is "Spar Urethane". I do not know anything about that material specifically.

Is this’paint’ or a 'waterproofer'? If you will be relying on this material as being your "waterproofer", I would suggest applying it directly to the wood and paint it after the fact.

Paints are not waterproofers and shouldn't be relied upon in most cases. You should use a paint that is extremely UV resistant and try to find one that claims to never ‘chalk’ under the presence of ‘extreme UV’.

[st4tic]

i dont think the UV will be that big of a concern since i will be running PC's and the paint will be outside the canopy, i was more concerned about the paint deterorating because of the moisture. But i will waterproof it first then paint it

[RandyStacyE]

<a href=showthread.php?s=&postid=8836245#post8836245 target=_blank>Originally posted</a> by st4tic
well im applying it to pine with primer on, but does the moisture from the tank on the paint release toxins or not? because im using a spray paint to paint the outsaide of the canopy i was just worried the paint being damaged.

I don't know if "Spar Urethant" is considered "Reef Safe".

I thought you were waterproofing the interior of a wood aquarium.

I'm not 100% positive, but I can't imagine that a painted canopy can release toxins into the tank unless it were submerged somewhere.

[st4tic]

im doing both but painting only the outside, spar urethane was reccomended by some reefers

[staticx]

Did you try to take my name, LOL
Paint it first then poly it

[st4tic]

well as of now im sealing it first then painting the outside, seems to be a lot of diff. opnions on this. But if someone has expereince on this ill seal it then paint then seal again

[rivdog]

Wow randy, when did spar urethane become "high performance"?. In a small nutshell, spar is "exterior Poly, or more commonly referred to as Marine varnish. Very well suited to the everyday encounters of reeefdom. ST4Tic, save yourself some steps and: first coat, reduce by 50%. 2nd coat full strength. 3rd coat full strength. Sand in betweeen coats, and tack cloth for the finer finishes. THE FIRST COAT OF THINNED POLY IS YOUR PRIMER.

[RandyStacyE]

<a href=showthread.php?s=&postid=8840245#post8840245 target=_blank>Originally posted</a> by rivdog
Wow randy, when did spar urethane become "high performance"?. In a small nutshell, spar is "exterior Poly, or more commonly referred to as Marine varnish. Very well suited to the everyday encounters of reeefdom. ST4Tic, save yourself some steps and: first coat, reduce by 50%. 2nd coat full strength. 3rd coat full strength. Sand in betweeen coats, and tack cloth for the finer finishes. THE FIRST COAT OF THINNED POLY IS YOUR PRIMER.

In my first post, I had no idea what he was painting and I didn't recognize the name "spar". I assumed he was sealing the interior of a wood aquarium. If it were an aquarium you would want to waterproof it and paint it after.

Only after I realized it was the canopy ... I noticed he was sealing the wood first.

[rivdog]

cool

[ElDiabloPollo]

Why not use marine epoxy to waterproof?

[st4tic]

well so far this is what i did:

1) used wood filler and then latex primer
2) sanded
3) put on 3 coats of spar urethane, waited a couple of hours between each coat
4) i will be painting the exterior of the canopy with black spray paint

[st4tic]

should i sand first the the spar before painting?

thanks