Polyurethane is one of the most popular finishing products used in crafts making. However, it can be problematic as bubbles and brush strokes often ruin its appearance at the end. Some DIY enthusiasts use a rag to apply polyurethane to avoid these problems, but is this a good idea?
You can apply polyurethane with a rag if you use the wipe-on variants. These formulas are less viscous and deliver better results where brush-applied polyurethane is problematic. However, you need to apply multiple coats of this product, wait until each layer drains, and work with a lint-free cloth.
I’ll look at why polyurethane applied with rags works great and the application process below.
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Why Use Wipe-On Polyurethane?
The main advantage of using wipe-on polyurethane is the smooth finish it guarantees when used correctly. However, some people also love these products because of their thinness. Applying some thin coats with a rag ensures less buildup in the corners of the material you’re working on.
This is why wipe-on polyurethane formulas are most useful when you’re working tricky jobs like on vertical surfaces and fine details. With buildup and drips eliminated, there’s a higher chance of doing a perfect job the first time.
The main downside to choosing this type of polyurethane made for rag application is that you’ll need multiple coats to get the same results as standard polyurethane. Where you’ll need five coats to get the job done with conventional polyurethane, you’ll need ten with wipe-on polyurethane. This can increase your overall budget for the project.
Can You Apply Brush-On Polyurethane With a Rag?
You can apply brush-on polyurethane with a rag, but all the standard downsides apply here. When applying on wood, you have to work in line with the grain to avoid raising the grain. You also have to pay attention to the quantity applied to reduce buildups and streaks as much as possible.
However, more brands are working hard to produce polyurethane that’s less problematic to apply with rags. For example, Miniwax has multiple polyurethane products (available on Amazon), which they say are easy to apply using rags. Some of these products dry quickly and can be cleaned easily with soap and water. This makes the application process a lot less frustrating.
How To Apply Polyurethane With a Rag
Whether you choose to go with wipe-on polyurethane or more conventional variants for rag application, you still need to go about the application process correctly for the right results. I’ll look at what you should do below, assuming you’re working on a wooden piece.
- Move the piece to a properly ventilated area.
- Sand the wood properly, starting with coarse-grit sandpaper (like 120) and finishing with 220-grit papers.
- Use a vacuum or tack rag to remove dust from the sanding process.
- Dip a lint-free rag in some mineral spirits to wipe down the surface.
- Stain the surface in line with the stain manufacturer’s instructions. You can skip this part if it’s not necessary for the project.
- Pour out the polyurethane into a container and use a lint-free rag for the application process. Wipe the polyurethane onto the surface in smooth, even strokes. Pay attention to ensure adequate coverage by overlapping strokes. Focus on one section and move down progressively.
- Wait a couple of minutes for the polyurethane to dry. Some manufacturers may recommend different wait times, though. Applying the second coat before the first one has dried will ruin your finish.
- Once the first coat has dried, sand the surface lightly using 320-grit sandpaper. Clean the residue with a vacuum or tack rag as before and wipe again with dampened lint-free rag (mineral spirits, not water!).
- Apply the second coat of polyurethane. If you need to apply a third, fourth, or fifth coat, repeat the slight sanding and cleaning process I’ve discussed above until you’re done.
Avoid sanding wood such as maple or pine using very fine sandpaper (above 220-grit) if you intend to use a pigment stain on the surface. Fine sanding on such wood can make taking on color a lot harder.
Also, even though multiple layers of polyurethane delivers better protection for the surface overall, you need to consider the aesthetic result you’ll achieve in the end. Multiple layers of polyurethane can be distracting, making the wooden piece look less natural overall.
You can apply polyurethane with a rag. The special wipe-on formulas are designed for this coating method, but you can also apply conventional brush-on polyurethane with a rag.
For the best results, use a lint-free cloth and apply the poly using smooth, even, and overlapping strokes.