# Paint over urethane? Urethane over paint?



## jtyson (Jan 17, 2015)

I've put together a custom rustic looking sign for a local shop. It is spruce. It will be hanging outdoors. It is two sided. I obviously need to get it sealed as well as possible to protect both the wood and glue joints. It is a large sign - 4'x6' roughly.

Originally, I was going to burn the lettering onto the sign. However, the shop owner has decided he wants it painted "carnival style" by hand. That's fine, but I won't be doing that work as it isn't really in my skill set. He will be taking the sign out of town to get it done in 10 days.

He is pretty dead set on using a product called One Shot for the paint. Considering that, I'm trying to figure out reactions between the paint and the sealer. I had planned to just use Helmsman spar urethane, but I'm not sure what to do now.

I've considered a thinned BLO, but I've never used that with paint. Either under or over. I've also thought about the idea that it could just be sprayed with a clear coat of the One Shot, though I don't know how that would turn out as I have never painted wood like that.

I'm kind of out of my realm of knowledge, so if anyone can lend some ideas, I'd greatly appreciate it.


----------



## wapakfred (Jul 29, 2011)

Well, I've not heard of 1 shot, but after just a little reading it appears that it's an oil based enamel intended for signs, a very good one I guess. As for what to do for an undercoat, here's my opinion: I wouldn't do either of the ideas you had. BLO wouldn't be of any use at all, though if it cures first the paint should stick to it very well. But expecting to seal the sign board from the elements is unrealistic. Helmsman is crap for outdoor use. It's simply a long oil urethane varnish, and urethanes are not all that well suited for outdoors. They break down quickly in a high UV environment, and in at least one test done by Bob Flexner, Helmsman was so poor at UV protection he conjectured it had none. Alternatives would be tinted paint, and that would probably offer the longest life of anything you could do. The lettering could be done over the top of it. If it's a clear finish you want, almost everything will eventually need some maintenance, but a true marine spar varnish (such as Epifanes or one of it's competitors) would last very long, be very expensive, and take several coats for max protection. The last alternatives i would consider would be a good exterior waterborne such as General Finshes HP or even better, Exterior 450. Finally, one last possibility: paint…but this time untinted. Oilbase exterior paint in the deep bases (used for mixing darker colors) dry looking like varnish (slight amber cast) have excellent UV protection, and a good long life. If that's of interest, read more here. Just be aware that the article is a little dated as oil based paint is increasingly hard to find. You might have to go to a real paint store, like SW. Best of luck!


----------



## jtyson (Jan 17, 2015)

I appreciate the response. Apparently the fella who is going to do the painting is going to finish the sign as he sees fit. That takes care of my part I guess. I'm going to be doing some research on the products you mentioned though for future use. Thanks!


----------



## nightguy (Aug 2, 2016)

> I appreciate the response. Apparently the fella who is going to do the painting is going to finish the sign as he sees fit. That takes care of my part I guess. I m going to be doing some research on the products you mentioned though for future use. Thanks!
> 
> - Jeremiah


Not a bad deal, takes all off your shoulders!!!


----------



## splintergroup (Jan 20, 2015)

Not an answer to your question in regards to outdoor durability, I have used poly over spray paint with great success.

I had some entertainment center shelves (BB plywood) that I wanted black and smooth as glass. Not having any black paint on hand with the exception of a few leftover cans of cheap flat black spray, I decided to try it anyway. I sprayed the shelves thoroughly, then smoothed the finish with 0000 wool (worked very easily), I then did the usual with the poly (several coats, 400 grit sanding with mineral sprits to flatten between coats). The shelves look like glass, black and no grain visible.

For outdoor 'worthiness' I'm a big fan of Epifanes. The box store 'spar' poly brands have left me disappointed, but the Epifanes restored my faith!


----------



## jtyson (Jan 17, 2015)

Well, the sign is sealed. The shop owner text me this morning with pictures. I'm having mixed feelings. The paint looks nice. It will definitely stand out. However, to me, we have lost the original "rustic" look of a wooden sign. Now, your average joe won't be able to tell if it is real wood, plastic, plywood, etc. I was under the impression that it was just going to be lettering and potentially some decorative bordering that was painted, and the rest of the wood would be left bare. It is too late now either way, but tell me what you guys think. Before and after. Excuse the mess in my mock up picture.


----------



## woodbutcherbynight (Oct 21, 2011)

If it were for a woodworking enterprise then painting it would be criminal. LOL For a tattoo shop the finished project is what I would expect to see.


----------



## jtyson (Jan 17, 2015)

Yeah I can agree with that. But still, I was excited to see something big and wooden and rustic looking hanging from the side of a building that I could call my handiwork. I don't really do a ton of wood work. Mostly steel. So the prospect was exciting for me to add to the portfolio. Maybe it would have been a different story if I actually did the painting myself. But if I did, it wouldn't look anything like that! Hand painting is not my gig.


----------



## woodbutcherbynight (Oct 21, 2011)

I built a table from mahogany supplied by a couple at church for their dining room. Had a beautiful finish on it.

They painted it white.

Go figure. LOL


----------



## dhazelton (Feb 11, 2012)

One Shot is what signmakers use, and guys who pinstripe cars because it flows out extremely well. It would have been nice if the guy told you what he wanted for an end product, that way you could have used a more stable plywood or whatever they use for highway department signs. I wouldn't waste anymore time being disappointed about it, take the money and run. Next time you know a few questions to ask.


----------



## Cooler (Feb 3, 2016)

I've used One Shot over latex paint. It is the absolute best paint for gold or silver with a high metallic solids for best effects.

I top coated the gold with oil based poly. And that is the route that I would take.

Here is a table top I painted with latex paint over MDF. I then used One Shot on the edges and then applied 3 coats of Minwax oil based semi-gloss over all surfaces.


----------



## jtyson (Jan 17, 2015)

Yeah I'm not nearly as bothered by it today as I was yesterday. Primarily because the picture he sent me was an in progress photo. The finished product looks much better.

Originally, he wanted it to look like an old timey rustic wood sign with the lettering burnt in, and some 3d carved filigree around the borders. But mid swing, he changed his mind and wanted it painted. Partially my fault, because the fella I was going to use for the pyrography flaked out on me. So while I was regrouping trying to find someone else, he decided paint was what he wanted anyway. I guess I could have scrapped the whole glue up and just cut it out of some plywood, but he liked what we had already, and I guess it still sort of lends to the rustic bit.

Anyway, here is what the sign looks like with the paint complete. For sake of finishing things, I'll post another picture when we get it up on the building later this week.


----------



## woodbutcherbynight (Oct 21, 2011)

Excellent!!!


----------



## jtyson (Jan 17, 2015)

Well, here it is complete and hung. Made some late in the game frame changes, but all in all it turned out pretty decent. Still wish I could take credit for the whole thing, but oh well.


----------



## wapakfred (Jul 29, 2011)

While I agree with the comments about painting over that wood, the guy's artwork is very good.


----------



## jtyson (Jan 17, 2015)

Oh most definitely. I never could have done the sign justice in comparison. You can't very well tell in the pictures, but in person, you can still see that it is an actual wood sign that is painted. Actually, while hanging it, we had a gentleman come by and ask to take pictures and commented on how this is the first "real" sign he's seen in a very long time. Not just digitally printed plastic or metal. So that was neat.


----------

