Each application method has benefits and drawbacks, but I’m going to zero in on wipe-on polyurethane.
So if you want to know how to apply polyurethane with a rag and the pros and cons associated with this method, you’re in the right place. Let’s dig in!
- Yes, you can apply polyurethane with a rag. This application method can be advantageous because it eliminates brush strokes and often leads to a smoother finish.
- All you have to do is dip the rag in the poly and then apply it to the workpiece. Polyurethane should be wiped on in circular motions to ensure evenness and maximum coverage.
How to Apply Polyurethane with a Rag
1. Gather Your Materials
Gathering all necessary materials before you start working is always a smart move. This way you don’t have to interrupt your project midway through to get something at the local hardware store.
You’ll need the following materials to wipe on polyurethane successfully:
- Polyurethane (oil-based or water-based)
- 2-3 clean microfiber tack cloths
- 1-2 empty containers
- Mineral spirits (paint thinner)
- Fine-grit sandpaper or steel wool
- A desk or floor fan
- Safety gear (gloves, respirator, goggles, woodworking apron)
2. Prep the Work Area
Once you have all the necessary materials, it’s time to prep the work area. Here’s how you can get the work area ready for your project:
- Lay out a tarp or an old bed sheet and set the workpiece in the middle; this way you avoid getting poly, mineral spirits, or soapy water on the floor.
- Make sure the windows are open so there’s decent air circulation; turn on a fan to help with this.
- Lay out your materials near the workpiece so you don’t have to stretch or bend awkwardly to get what you need.
3. Prep the Workpiece
Prepping the workpiece is one of the most important parts of the process. If the surface is ready to receive polyurethane once you start applying it, there’s a very good chance you’ll reach a successful outcome, if you apply the poly correctly.
First, wash the workpiece with mineral spirits or warm soapy water; use a clean cloth to apply either liquid.
Personal note: I like mineral spirits because it’s stronger and you don’t have to do any mixing to use it.
After the workpiece has been thoroughly cleaned, let it dry for 1-2 hours. After this time has passed, check to see if the surface is dry. If it is, continue to the next step; if not, wait another hour or two.
Have you ever tried tinting polyurethane? It’s a great way to add some color to your projects!
I’m only referring to this step as “sanding” because sandpaper is involved. In reality, your goal should be to rough up the workpiece—not sand it down to make it smooth.
Polyurethane adheres better to a rough surface, mainly because the wood’s pores are more exposed.
To be clear, poly isn’t totally absorbed like wood stain, but a small amount does make its way into the pores; think of this small amount a base coat within a base coat.
I like sanding with fine-grit sandpaper, but you can also use steel wool. Just make sure you stay away from coarser sandpapers, as these may take off too much material.
And when you sand, don’t apply too much pressure, as doing so may result in you taking too much off the wood surface.
5. Wipe on the Poly
Now it’s time for the main event: wiping on the poly.
You should do this with a clean cloth or rag, preferably a microfiber one.
It’s best to stay away from old bath towels and t-shirts, as these may be too rough. If they are, they may prevent you from achieving a smooth finish.
After stirring the poly for 3-5 minutes, dip the cloth in. The goal here should be to get just enough to rub on—you definitely want to avoid over-saturating the cloth.
Don’t wipe the sides of the can or container, as doing so will increase the chances of bubbles forming when you wipe on the poly.
When you apply the poly, wipe in a circular motion to ensure adequate coverage.
Again, refrain from applying too much pressure, as doing so will prevent you from spreading the poly evenly.
If the workpiece has a straight grain, apply WITH the grain (as opposed to against). But if the grain pattern is hard to discern, don’t worry if you can’t follow it—it’s not the end of the world.
Lastly, it doesn’t matter if your swirling motion goes horizontally or vertically; the important thing is that every inch of the workpiece gets adequately coated with poly.
I chose to including waiting as a sixth step because it’s important and arguably the hardest step to carry out correctly.
If you don’t, when you go to apply the next coat, you’ll take off some of the poly you put on earlier, and eventually you’ll have a big mess on your hands; you may even have to redo what you did hours ago!
To ensure you allow enough time for drying, look on the poly can to see what the manufacturer’s recommendations are.
Usually, water-based poly coats take 30 minutes to an hour to dry, whereas oil-based poly coats can take 5-7 hours to dry.
Once the polyurethane coat is dry, repeat steps 4-6 for all subsequent coats.
If you need more help, check out the video below!
Pros of Applying Polyurethane with a Rag
If a smoother finish is what you’re after, wiping on poly is the way to go. You avoid brush marks and it’s easier to even the poly out.
Plus, if you know what you’re doing, you can ensure you only apply thin coats and avoid air bubbles.
So long as you know how to apply the right amount of polyurethane and don’t waste rags, using a lint-free rag to wipe on polyurethane is a much more cost-effective application process, mainly because you won’t waste polyurethane.
If you’re applying polyurethane with a foam brush or foam roller, over-saturating the workpiece is more likely, especially if it’s your first time using either applicator.
Don’t mind the process taking a little longer? Then you can apply poly a little bit at a time to eliminate waste and ensure even, thin coats.
Since a microfiber tack cloth fits in the palm of your hand and is guided by just a few fingers, you’ll have much more flexibility when applying poly, so it’ll be easier to get at those hard-to-reach places.
None of the other commonly used applicators can provide this level of flexibility; the only one that comes close is a sprayer, but you really need to know how to operate this to avoid over-spraying.
Cons of Applying Polyurethane with a Rag
To wipe on polyurethane properly, you’ll need to take your time, which means that wiping on poly generally takes longer than every other application method.
But if you take the time to do things right, you’ll be rewarded with a remarkably smooth finish—trust me!
That said, if you’re in a rush and all you need to do is apply a couple thin layers of poly to bare wood, choose another application method.
Wiping on polyurethane is beneficial in numerous respects, but it’s not the easiest thing to do, especially if you haven’t wiped on finishes before.
Getting the right amount of poly on the cloth is by far the most challenging part. If you don’t dab the cloth enough, you won’t have enough poly to spread.
If you over-saturate the cloth, you might as well get rid of it, as it’ll be much harder to apply the right amount of polyurethane after this happens.
Wiping polyurethane on vertical surfaces is rather difficult, though this is the best application method for these surfaces.
In the end, no matter how much reading and video watching you do before, you can’t avoid the trial and error that must be endured before you can apply polyurethane like a pro.
Should You Apply Polyurethane with a Rag, Brush, Roller, or Sprayer?
Using a rag to apply polyurethane is the best option if your top priority is achieving a smooth, even surface.
This method of application will take longer, but if you do things right you could achieve a very nice finish.
Regular cloth will do, but if you want best-in-class results it’s better to choose a microfiber cloth.
You can apply polyurethane efficiently with a brush, but there’s a chance brush strokes will be prominent after the poly dries.
That said, if you apply brush-on polyurethane the right way, the chances of unsightly brush marks being visible are low.
Using a soft, natural-bristle brush is best, but foam brushes work too.
A roller is the best applicator if there’s a lot of polyurethane to apply, which explains why you’ll often see rollers used to apply polyurethane to floors.
The only problem with rollers is they’re not very flexible. Also, if you’re not careful, you could end up applying way to much poly, in which case you’d have to remove excess polyurethane before continuing.
Spraying polyurethane can also achieve a consistent coat, but only if you know how to use a sprayer. This method only works with water-based polyurethane; oil-based polyurethane is too thick.
Tips to Apply Polyurethane with a Rag
Use a Wipe-On Polyurethane
Some polys are designed to be wiped on. Minwax makes a good wipe-on poly, and I’ve found it complements wood finish well
Use Steel Wool for an Ultra-Smooth Surface
To achieve a flawlessly smooth surface, consider using 00 steel wool instead of sandpaper. But just use it on the last layer; using it on the first coat will take off to much material, especially if it’s a thin coat.
Sand by Hand
You should never use an orbital sander during the poly application process. This power tool will take off too much material and cause the overall finish to be uneven.
Plus, it’ll generate a ton of sawdust, and if you don’t have a bag for collecting this an unnecessary mess will be created.
Sure, it takes a bit longer, but sanding by hand is worth it—this I can attest to with 100% confidence.
Safely Dispose of Poly-Soaked Rags
Once you’re done applying polyurethane, you need to properly dispose of the polyurethane-soaked rags.
Under no circumstances should you leave these around, as they’ll be highly flammable.
If your city or town has a hazardous waste collection day, you can get rid of them then. Or you could bring them to a local hazardous waste dump.
In the end, wiping on polyurethane finish is beneficial for numerous reasons:
- This way you ensure an even surface.
- You’ll waste little to no polyurethane.
- You can get at those hard-to-reach places.
But applying polyurethane with a cloth isn’t the easiest application method, and it definitely takes longer than brushing, rolling, or spraying.
That said, if achieving a silky-smooth polyurethane surface is your number-one priority, wiping on polyurethane is the way to go.