Sanding is an effective way to remove varnish from wood. So, what grit sandpaper to remove varnish from wood?
Varnishes are among the preferred wood finishes for protecting the wood, paint, or stain. However, it yellows over time, and you may have to take it off. You may also be in a situation trying to repair a poorly varnished surface.
Regardless of your reason for removing varnish from wood, using the correct sandpaper grit is crucial. And that’s what this article is about; what grit sandpaper to use and other methods of removing varnish from wood.
What Grit Sandpaper to Remove Varnish from Wood?
The best sandpaper grit to remove varnish from wood is 150-grit sandpaper. Start sanding with 150-grit until you get to bare wood. Then, finish sanding with 220-grit sandpaper to even out the wood’s surface.
How to Remove Varnish from Wood Easily Using Sandpaper
Sanding is a natural and chemical-free method that removes almost any type of varnish or finish from the wood. However, sanding is labor-intensive, especially when removing varnish from large surfaces.
Knowing what grit sandpaper to remove varnish is one step in the right direction. Follow the procedure below to remove all the varnish from the surface.
Materials and Supplies needed
- Dust masks
- Hand gloves
- 150-grit sandpaper
- 220-grit sandpaper
- Sanding block
- Drop cloths
Step 1: Prepare the work area and wood surface
Removing varnish by sanding produces a lot of dust and can be messy. Follow these guidelines to prepare your working area and the surface before sanding.
Ventilate the workstation if you are working indoors by opening windows and doors. But if the varnished surface is mobile, work outdoors. Then line the floor and seal off surfaces and furniture using a drop cloth or dust sheets.
Also, ensure that you wear protective goggles, a nose mask, and hand gloves. Finally, remove hinges, nails, and screws from furniture, wooden doors, and tabletops before you start removing varnish.
Step 2: Sanding the varnished wood
Start sanding using 150-grit sandpaper. Always sand the flat surface in the direction of the wood grain to avoid splinters and scratches.
You can use an orbital sander when working on large flat surfaces. Alternatively, you can opt for a sanding block to remove varnish on smaller and tighter spots.
Collect the sanding dust using a shop vacuum or manually brush them off the surface with a broom.
Sand the surface further using 220-grit sandpaper. Go over the whole piece of wood until all the varnish comes off. Pay attention to the curved surfaces as well.
Interesting read: Sanding sealer versus polyurethane.
Step 3: Vacuum and tack the dust off the surface
Again, vacuum the dust from the latest round of sanding. Then you can clean the surface further by wiping it with a tack cloth.
Still, you can use a damp cloth to collect all the dust. Look out for any rough spots you may have missed and smooth them out.
Other Ways of Removing Varnish from Wood
Other than sanding, there are other ways to remove varnish from wood.
Method 1: Stripping Varnish from Wood using a Heat Gun
A heat gun softens and loosens varnish from the wood, making it easier to remove. Wear protective goggles and heavy-duty gloves. It also helps to have a fire extinguisher close by if you need to put off a fire.
What you will need:
- Lint-free cloth
Step 1: Wash the varnished surface
Use warm soapy water to wash off dirt and other contaminants that may be flammable. Pat the surface dry with a lint-free cloth.
Step 2: Heat and scrape the varnish
If you’re using a heat gun for the first time, first read the user manual carefully to know how a heat gun works. Then, set the heat gun to low or medium heat.
Hold the heat gun close to the spot you want to soften. Heat the spot until the varnish shrinks. Then, gently dig the scraper below the varnish, and push it in the direction of the grain. The softened varnish should come out rolling.
Repeat the process for the entire surface.
Step 3: Finish tight spots with sandpaper
Use hand sandpaper or sanding block to remove leftover varnish patches in tight spots.
Method 2: Removing Varnish Using a Stripper
Stripping is the easiest and most effective way to remove varnish from wood. This method is faster and doesn’t require too much effort.
Although strippers have been improved over the years, it’s important that you wear protective equipment and work outdoors or in an adequately ventilated area.
There are two formulations to choose from when considering a varnish or paint stripper; caustic and solvent-based strippers.
Solvent-based strippers penetrate deep into the wood fibers and soften the varnish. They have a strong fume and are best suited for outdoor use.
Caustic strippers, on the other hand, are fit for indoor use as they don’t have a strong odor. Anyone can use Citristrip stripping gel as one of the safest strippers.
Supplies you’ll need:
- Safety goggles
- Nose mask
- Drop cloths
- Disposable brush
- Metal scraper
- Varnish stripper
Step 1: Prepare your work area
Wear your safety gear and open windows and doors if working indoors. Seal off the floor, walls, and other delicate surfaces using a drop cloth or newspapers.
Step 2: Apply the stripper
Use a disposable brush to apply a generous amount of varnish stripper on the wood surface. It will often have a thick consistency, so ensure you coat the entire surface.
Step 3: Wait for the stripper to work
The standard waiting time is between 30 minutes and 1 hour. But you should check the manufacturer’s recommended wait time for the varnish stripper to work.
While you wait, you can cover the coated surface using saran wrap or a painter’s tarp. This will keep the stripper from evaporating and drying out prematurely.
Step 4: Scrape it off
Use a metal scraper to gently scrape off the softened varnish. Collect the sludge in a container. Again push the scraper along the grain.
Repeat the process if there are spots with the varnish still intact.
Step 5: Rub stubborn spots with steel wool and mineral spirits
Use fine steel wool with mineral spirits to rub the leftover varnish from stubborn spots. Rub in the direction of the wood grain.
Step 6: Finally, neutralize the wood
Wash the wood with warm soapy water. Wipe off excess water and let the wood air dry. But if the stripper recommends a specific neutralizer, use that.
DIY Varnish Remover
Homemade varnish remover is affordable and safer to use compared to chemical strippers.
- Boil 4 cups of water
- Dissolve one cup of cornstarch in half a cup of cold water.
- Pour the hot water into a bucket and then add the cornstarch, 3/4 cup baking soda, 1tbsp: white vinegar, and ½ cup ammonia. Stir to mix.
- Use a bristle brush to apply the hot mixture to the varnish.
- Wash off the loose varnish with a cloth dipped in hot water.
Is It Better to Strip or Sand Varnish?
Stripping Varnish is way better than sanding. Stripping works fast to strip old finishes like shellac, lacquer, stain, and paint. On the other hand, sanding can remove varnishes but is messier and labour intensive.
Also Read: How to Get Oil Stains Out of Wood
Can You Sand Off Polyurethane?
Absolutely! You can sand off polyurethane in the same way you would a varnish. Begin with 150 grit sandpaper to remove the most. And then finish sanding with 220 grit sandpaper. Whether you use a sanding block or orbital sander is up to you.
Also, check out the methods of removing wood polyurethane without sanding.
How Does Vinegar Remove Varnish From Wood?
Vinegar is acidic and will cut through most varnishes. To make a potent vinegar solution, mix 4 cups of hot water with½ a cup of ammonia and 1 tablespoon of white vinegar, and ¾ cup of baking soda. Stir well and apply the mixture to the varnish to strip it.
How Do You Remove Varnish From Wood Without Sanding?
Using a chemical stripper or DIY varnish remover, you can remove varnish from wood. Brush the stripper onto the varnish, let it sit for a while, and then scrape off. Alternatively, you can use a heat gun to soften the varnish and scrape it off the wood surface.
What is the Easiest Way to Remove a Wood Finish?
The easiest way to remove the wood finish is by stripping it. Apply a generous coat of stripper, let it sit, and then scrape it off. You’ll remove the varnish without breaking a sweat.
Read also: Difference between polyurethane and varnish.
Will Paint Thinner Remove Varnish From Wood?
Yes, it will. Denatured alcohol dissolves shellac while a lacquer thinner will dissolve and strip lacquer from wood. Rub the varnish using fine steel wool and the respective thinner.
Related Post: What Grit Sandpaper is Equal to 0000 Steel Wool
What grit sandpaper to remove stain from wood?
Removing stain from wood can be extremely difficult. You may sand the stained surface using 100-grit sandpaper. However, the better solution to restore bare wood is to remove the top layer by planning.
How to remove old varnish from wood
- Clean the surface to remove debris.
- Start sanding the entire surface with 150-grit.
- Proceed to sand further with 220-grit sandpaper.
- Vacuum the dust and clean the surface.
What grit sandpaper for stripping furniture
Use 150-grit palm sandpaper to cut through the tough finish on the furniture. Finish sanding using 220-grit fine sandpaper to smooth any tiny scratches to even out the furniture surface.
What grit sandpaper to remove paint from wood
A 40-60 grit sandpaper is the best sandpaper for removing paint from wood as long as the grits of the sandpaper are very coarse enough to sand the paint off.
Final Thoughts on What Grit Sandpaper to Remove Varnish from Wood
Varnish isn’t difficult to remove. Once you have 150-grit sandpaper, you can remove thick layers of varnish and then finish with 220 grit.
If sanding isn’t your preference, you can use a varnish stripper or a heat gun to get the same results. Although you can’t run away from sanding, can you?
You may want to read our blog on what grit sandpaper for deck sanding for your next project.