Varnish for acrylic-painted sign

Looking into the near future....
my bondo'ed sign will be painted with Golden acrylics...
as I need to keep it within the range/look of the rest of my work.
I don't have much experience with my work being out all day/all weather/all temperature.
I'm in Wisconsin...
although, it will be brought inside at the end of each day.
I'm just fishing for alternatives to pick from...
The Golden company has a varnish 2 b diluted with mineral spirits or turp that is outdoor worthy.
There is some way pricy stuff I read about here...$155.00 a gal...or something like that, which is beyond my price range...
Spar varnish and marine varnish are two other choices...
anyone out there have any experience with an acrylic painted sign that was varnished with something?
I may wind up using the Golden product...
but, thought I'd toss the question out there just in case someone has already been through this.
thanks...
Linda

Hi Linda
Anything you use needs to have UV inhibitors. I was chainsaw carving and i used Minwax Helmsman spar. I also build rustic furniture and use it for that too. I built Deb a pine trash bin with a smoked acrylic lid. The lid has a mitered wood frame. I carved and textured lettering in the acrylic then painted it with acrylic paint. She has an apple theme going in her kitchen. So before the last coat of spar, i hand painted an apple with leaf on the front in acrylics. Then applied the final coat of spar. I steel wooled between coats for a smoother finish,(i painted over the steel wooled finish) except around my apple painting. Not on the final coat though. (3 coats) No problems and the painting is protected.
IF i recall , your using MDF sawdust board for letters? You need to make sure its well sealed all sides and surfaces. any corners rounded, sharp edges will open the finish over time and let in moisture. The backboard you mentioned was MDF but you werent sure? Might it have been MDO ? sign plywood with one or both sides looks like brown paper bag surface, real smooth? if so it should be sanded litely with a finish sander to remove glaze and promote adhesion of primer, filling edge voids with wood putty. Also, body putty taking too long to set up. More than say 20 minutes means you didnt use quite enough hardener. I used to do bodywork and paint. If this has been answered in another post, i'm sorry. Been up all nite. rick

Geez, Rick...I hope you get to catch some sleep!
I've gorilla glued and screwed the "sawdust board" down, got carried away with the bondo sealing up little gaps and places where the edges didn't exactly meet perfectly, and I've got a flat oil based primer to use even before the real paint gets close to the piece.
UV inhibitors...ok....
I read somewhere last night that spar varnishes on front doors need to be redone ever couple years...
I'm not really fired up about having to strip down a varnish to redo it...
and won't varnish stripping mess up the painting (acrylic) underneath and need repainting?
Perhaps I've stepped into a complexity I was not expecting....
not insurmountable though.
The sign will be in town, so I can attend to it periodically.
I know things don't last forever,
but, I'd like to sell something that's as durable as I can pull off.
I'm having a ball with this...it's for a butchershop, and they are asking about more.
I'll post what I wind up with if there is interest...
thanks...Linda

linda
I have real trouble getting sleep. But anyway. I read your reply here and suddenly realized that your not going to have any natural wood showing anyway, i dont think. One shot paint is all i use in that case. Paint is by far better outside. No need for a clear over it. If you did , id use one shot clear, but i dont think you need it at all. Now if your gonna use an oil base primer, i dont know about bonding acrylic to it. with out a spar overcoat. Maybe some else has experience there. Usually you can do oil over acrylic but not acrylic over oil... rick

Speaking of clear coats... Has anyone experimented with clear coats that come in spray cans. I have seen a great number of clear coats now available. Just wondering if anyone has any experience with outdoor exposure. Maybe I need to paint and clear coat something and sit it outdoors.

Any comments?

Hi jay
The best of those in my humble opinion, would be Minwax helmsman. But i never use it. Any of those spray bombs are mostly proppelant(SP). It would take alot to build up a decent finish. If other kinds and brands are for exterior, i doubt there would be enough UV inhibitor in it to be any good. I wouldnt even trust Helmsman in the regard either. I'd not be happy to paint or carve or whatever, put time in something and have the finish fail quickly. Having said that, there is no clear made that will hold up in direct sun. I will say this, i did an mdo sign for the local internet provider, 12 years ago. It was mounted to 2x4's on a brick wall up above. That wall faces north. To this day that sign looks as good as the day i hung it. Good thing, i did eleven different painting techniques in it. It has 1 shot clear over it. 3 or 4 coats. Even the base color has clear in it, as i did a green marble technique using it. 1/2" mdo , but i airbrushed a border on it, makes it look like its 4 inches thick.

There's an artist guy around here,
who, over the last 4-5 years or so, has his signs popping up all over the place by some really great places.
He's the one who told me about the FLAT oil based primer, that you sand a bit for tooth, and then put acrylic over....
it's an alkyd primer, I don't know that one can get the old fashioned oil base primers anymore.
I know the paint shop in town highly recommends oil/alkyd base priming raw outside wood before painting...
and then say you can go over it with anything.
I'm hoping I'm going to be ok...
especially if I'm really good about varnish protecting all from weather.
I did see the art supply shop in Madison had 1Shot
clear something..."repair"?
No one there could tell me anything about it's friendliness with acrylic....
so, I went the direction of Golden's Hard MSA Varnish with UVLS...thinned with mineral spirits...supposed to be extremely tough, weather worthy, crystal clear, and for hard supports only, which is what I got.
It's the varnish on all these life sized painted plastic cows that stand about Madison now.
So, I guess I keep going and keep my fingers crossed....Linda

Linda,

Isn't this a great Forum!

Many of us older guys have moved on with the basics behind us, but it's allways good to drop by and see posts from newbie's.

There are still many oil based primers on the market. There used mainly to coat out Cedars,
Redwoods or any substrate which needs to capture tannins or previously painted surfaces.

In the sign trade, there know as Block Out white. Look at Lowe's or Home Depot for Zinzer or Kilz. I prefer the Alchohol based of these. They come in Oil, Water, or Alchohol base. Remember if you buy the Alchohol variety, only alchohol will clean brushes.

Clear Coating:

I've experienced considerable failure with clear coatings. My friends on the coast use Sickens or high tech spars. It raises the specture of failure for us. Our only clear is catalized Matthews or most any automotive variety. They won't yellow. Be very carefull as they will lift paint if applied very heavy on the first coat.

Keep up the good work.

Joe
www.normansignco.com