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I'm building a desk out of birch plywood. I had planned on painting it the same color as the trim and bookcases in my office. (I have leftover latex paint from that recent project.) I was thinking I should seal it with polyurethane so it would hold up if the kids set a wet glass or something on it, but as I was researching that I've started to second guess if that's the best plan. Thoughts/advice for a newbie? Thanks in advance.
 

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Latex paint will be a seal once it has cured.

Birch plywood may not make for the smoothest surface. The grain may tend to be raised by the water in the latex paint. The latex coat may also not be as smooth as you want for a desk surface.

If you want to seal the birch plywood to prevent the grain from raising, get Zinsser SealCoat from a local big box or hardware store. This goes on easily with brush, roller, or sponge brush. Dries fast and can be top coated by polyurethane or paint.

I like to leave the wood natural, so my preference would be to topcoat with polyurethane.
 

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If any of the grain rises, and most woods do, wait until the first finish coat is set up good and hard.
Gently rub the surface down with the coarsest steel wool that you can buy. The fine stuff is useless. Your sense of touch/fingertips will tell you whe you're done.

The strands in the coarse SW are flat. The mass of it cuts like a million little chisels. Further finish coats should sit flat.

I'm making an umbrella stand from 4 panels of western red cedar, the outsides are relief-carved animals. Seems to me that most good umbrellas are made of extremely fine, woven cloth. Don't need that catching!!!!. MinWax Tung Oil Protective Finish a week ago. Steel wool today and my, but that interior surface is going to be slick. Four coats will be glossy, I can repeat the steel wool part if I have to. Then the assembly with glue and pegs. Then the outside.
 

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If you mean to put a oil based polyurethane over the latex paint it would be a bad idea. The paints aren't completely compatable and oil based poly yellows as it ages altering the color of the paint. If you are going to use a poly use the water based.

I believe furniture deserves better paint than latex. If it were me I would go to the trouble of using an oil based enamel. The oil based enamel usually dries in 24 hours and can be recoated. The weather says a lot about drying time. If it is cool and damp it may take 48 hours for a coat to dry. When you sand it between coats if it tends to gum up on the sandpaper it isn't ready yet for recoat. After it is done it would be ready for light use in 48 hours but I would wait a week or two before putting anything heavy on it. The finish is dry but not cured and a bit soft. A heavy item can leave a dent in the finish. There will be a little offgassing for two weeks to a month but hardly noticable.
 

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If you mean to put a oil based polyurethane over the latex paint it would be a bad idea. The paints aren't completely compatable and oil based poly yellows as it ages altering the color of the paint. If you are going to use a poly use the water based.

I believe furniture deserves better paint than latex. If it were me I would go to the trouble of using an oil based enamel.
Yes, I had read about using a water based poly to avoid the yellowing. Through that research I saw some comments about enamel, so I was wondering if that might be a more appropriate choice. Would I need a primer beforehand?
 

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Yes, I had read about using a water based poly to avoid the yellowing. Through that research I saw some comments about enamel, so I was wondering if that might be a more appropriate choice. Would I need a primer beforehand?
You could use an enamel without primer however it would be more labor intensive. To make a nice finish it will take several coats sanding it between coats and enamel doesn't sand very well. A primer is easier to sand and has more solids so it builds quicker. You would get the desk sealed and sanded really good with the primer and the first coat of enamel would lay down really well. Then only a really light sanding preferably wet sanding with 400x sandpaper and the second coat should lay down perfect. I would recommend spraying the paint if you have the equipment. If you have an air compressor a cheap harbor freight sprayer would work fine.
 

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Do you have the capability to spray lacquer?

Two years ago I built a student desk and hutch for one of my granddaughters. All of the plywood used was birch. The finish was sprayed lacquer undercoat followed by several layers of white lacquer.

The top of the desk came out very smooth and durable. There was absolutely no grain problem.

I am now in the process of building the same desk for a second granddaughter. In the area where I live finding good plywood is difficult. Two days ago I went shopping for a top as the one I had did not look good. I had to buy a piece of oak ply as I would not take any of the birch out of the stores.

This time I will have to spend more time prepping the top because of the open grain of the oak.

George
 

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We have an introduction section where you can say a few words about yourself. If you fill out your profile in your "User Control Panel", you can list any hobbies, experience or other facts. You can also list your general geographical location which would be a help in answering some questions.

IMO, latex paint would be too soft for a desk top. An oil base paint would take a long time to dry, and give off some odor. There would also be a blocking problem (things sticking to it after it dries).

I would use a waterbased polyurethane suitable for flooring and add a tint base for the color you want. A first thin sprayed application doesn't raise the grain that much, and the normal in between application sanding eliminates any of it. The media dries fast, stays clear, and cleans up with water. There's very little noticeable odor.










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If "latex" means something like wall paint, it's a really bad idea. It has a property called blocking, where anything sitting on it for a while will actually stick to it. Top coating it with a varnish is an ever worse idea. If you don't want to use an oil based enamel (which would likely be the most durable) consider an acrylic enamel. These are water borne, and do very well...quick dry time, and easy clean up. Personally I'd prime the top first, probably with Zinnser BIN, or maybe an oil primer. Some acrylic enamels are labeled acrylic latex, but they made for this type of service unlike the wall paint.
 

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Thanks for all the input. I hope I haven't bitten off more than I can chew! In the past I've made desks out of hollow or solid core doors and just sat them on filing cabinets. I thought this time I'd go a little more 'upscale' and actually build something. I could've gone the easy route and grabbed this desk from IKEA http://www.ikea.com/us/en/catalog/products/S49001965/#/S69929643 But I wanted something a little longer and instead of generic white thought I'd match it to the trim color in the office.

I have a big garage I could work in, or I could do it outside and move it inside overnight. I'll probably have to wait til it's warmer out. I don't have a sprayer, but wouldn't be opposed to picking one up. My fence needs restained, I could probably reuse it for that. I do have woodworking friends I could probably borrow things from as well. If I went a brush route instead of a sprayer, is there a certain type of brush I would want to use? Thanks again, and excuse my ignorance...I'm not a pro--just an overambitious mom who refuses to pay the $550 a pro quoted for building this desk. LOL
 

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I am a retired biology/Wood Science prof. I have sat at desks or stood at research lab benches for more than 60 years. The sheer durability of the bench/desk top is something that I notice.
You could cut to the chase and stick down a sheet of Arborite/countertopping.
 

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You don't have to use a sprayer but it would make it a great deal easier to get professional results. If you use a brush use the softest brush you can find and apply the paint as thin as you can with as few strokes as possible. The more you brush it the more the brush marks show. Then if you use a stiff brush it would be like applying paint with a broom.

If you have compressed air you could use a cheap Harbor Freight sprayer. I get them for about 20 bucks with one of their 20% off coupon. This type sprayer wouldn't be very good for a fence. You really need it attached to a pressure pot or use an airless sprayer for that application.
 

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Discussion Starter #13
Got it all primed/sanded. Any thoughts on using Sherwin Williams All Purpose oil based enamel vs. something in their ProClassic line such as ProClassic Alkyd Interior Enamel? Thanks!
 

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Either the All Purpose Enamel or the ProClassic Enamel could be used. The Proclassic is available in more sheens though and perhaps match your latex woodwork paint better.
 
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