If you're trying to figure out how to apply General Finishes High Performance Top Coat for your next furniture project, you've probably heard that it's one of the most durable water-based finishes on the market. It's a favorite for a reason—it doesn't yellow over time, it's tough as nails once it cures, and it dries incredibly fast. However, because it dries so quickly, it can be a little intimidating if you've never used it before. If you aren't careful, you might end up with streaks or bubbles that are a total pain to fix later.
I've spent a lot of time working with various top coats, and I can tell you that the "High Performance" line from General Finishes is a bit different from your standard hardware store polyurethane. It's thinner, it levels out beautifully, but it requires a light touch. Let's walk through the steps to get that professional, smooth-as-glass finish without losing your mind.
Getting the Prep Work Right
I know, I know—prep work is the boring part. Everyone wants to jump straight to the satisfying part where the wood starts glowing, but if you skimp here, the top coat will highlight every single flaw. First off, make sure your piece is sanded properly. If you're applying this over raw wood or a fresh stain, you should usually sand up to about 220 grit. Anything finer than that might close the pores of the wood too much, and the finish won't have anything to grab onto.
Once you're done sanding, you have to get rid of every single speck of dust. I like to use a vacuum with a brush attachment first, followed by a slightly damp microfiber cloth or a tack cloth. If you leave dust behind, it'll get trapped in the finish and feel like sandpaper once it dries. Also, make sure your workspace isn't a wind tunnel. If you have a fan blowing or a vent pushing air right onto your project, the top coat will dry way too fast, and you won't get a smooth finish.
Picking the Right Tools for the Job
When it comes to how to apply General Finishes High Performance Top Coat, the tool you choose makes a huge difference. You have a few options here: a high-quality synthetic brush, a foam brush, or a foam applicator pad.
I usually suggest staying away from cheap bristle brushes because they leave massive streak marks. A high-quality synthetic brush (like a Wooster or Purdy) is great for nooks and crannies. However, for large, flat surfaces like a tabletop, a foam applicator pad is a game-changer. It holds a lot of product and lets you lay down a thin, even layer without much effort. If you're feeling fancy and have the equipment, you can also spray this finish, but for most DIYers, a hand application works just fine.
The Secret to a Smooth First Coat
Before you dip your brush in, give the can a good stir. Never shake the can. Shaking creates tiny air bubbles that will end up on your furniture and look like little craters when they pop. Stir it gently with a clean stick to make sure all the dulling agents (if you're using Satin or Flat) are mixed back in.
When you're ready to start, load your brush or pad with a decent amount of product, but don't let it drip everywhere. Start at one end of your piece and work your way to the other in long, continuous strokes. The trick with this specific top coat is to not overwork it. Once you've laid it down, leave it alone. If you keep brushing over the same spot as it's trying to set, you'll create "drag," which leads to those annoying brush marks.
It's also helpful to "back-brush" or "feather" the edges. This means you lightly run your brush over the transition area between two passes to blend them together. Do this while the product is still very wet. If it's already starting to feel tacky, back off—you're better off fixing a small bump later than creating a huge mess of texture now.
Why Sanding Between Coats is Non-Negotiable
After your first coat is on, you need to wait. General Finishes says it can dry in 1-2 hours under ideal conditions, but I usually give it at least 3 or 4 hours depending on the humidity. Once it's dry to the touch and doesn't feel "rubbery," it's time to sand.
You might be thinking, "Why would I sand off what I just put on?" It's not about removing the finish; it's about smoothing it out. The first coat often raises the grain of the wood, making it feel slightly fuzzy. Use a 320 or 400-grit sanding sponge and lightly—and I mean lightly—scuff the surface. You're just looking to knock down any dust nibs or bubbles. When you're done, the surface should look a bit dull and feel like silk. Wipe away the new dust, and you're ready for coat number two.
Building Up the Protection
For most projects, three coats are the "sweet spot." The first coat seals the wood, the second coat builds the depth, and the third coat provides the ultimate protection. If you're doing something that's going to see a lot of action, like a kitchen table or a desk, you might even want to go for a fourth coat.
Just repeat the process: apply a thin layer, let it dry, scuff sand, and wipe. You'll notice that the second and third coats go on much smoother than the first one because the wood isn't soaking up the product anymore. It'll start to look more like a professional finish with every layer you add.
Dealing with Humidity and Temperature
One thing people often forget when learning how to apply General Finishes High Performance Top Coat is the environment. Water-based finishes are sensitive to the weather. If it's a super humid day, the finish will take much longer to dry. If it's incredibly hot and dry, it might dry so fast that you can't even get across a tabletop before it starts to set.
If you find that the product is drying too fast and leaving streaks, you can actually mix in a little bit of General Finishes Extender. It basically thins the product out and gives you more "open time" to work with it. It's a lifesaver for big projects like dining tables where you need a little extra time to blend your strokes.
Final Curing and Maintenance
Once your final coat is on, don't touch it! Give it a full 24 hours before you even think about moving the piece into your house. Even though it feels dry, it isn't "cured." Curing is a chemical process where the finish reaches its maximum hardness, and for water-based poly, that usually takes about 7 to 14 days.
During that first week or two, be really careful. Don't put heavy objects on it, and definitely don't use any cleaning chemicals. Just a dry cloth is all you need. Once it's fully cured, it's incredibly durable and can be cleaned with a damp cloth and mild soap.
Learning how to apply General Finishes High Performance Top Coat isn't really about having a magic hand; it's just about patience and using the right technique. Don't rush the drying times, don't over-brush the product, and always, always sand between your coats. If you follow those simple rules, you'll end up with a finish that looks like it came straight out of a high-end furniture showroom. It's a fantastic product that really rewards the effort you put into the prep and application stages. Happy finishing!