How to Remove Varnish from Wood
To apply varnish or stain to a piece of wood you first need to remove the old varnish and stain off. Removing the varnish isn’t difficult and with a few tools anyone can do. Here is what I recommend doing.
How do you remove varnish from wood? To remove varnish from wood, you can use a solution like citrus strip or a heat gun and putty knife to remove the varnish. Both methods require you to sand the surface afterwards.
There are several reasons why you might want to remove varnish. The old varnish may have been applied wrong and you want a cleaner look. Or the furniture is old and you want to apply a fresh new coat of stain on it. Either way, getting the varnish off properly is important and can go a long way to restoring your furniture and making it look right.
Using a heat gun and putty knife
This option requires more effort than the other options. You will need a heat gun and a knife. I recommend getting this heat gun and this putty knife as they seem to work the best for projects like this.
Put your heat gun very close to the wood surface but not touch the wood surface. Start the heat gun and wait for bubbles to occur. When you see bubbles that means the varnish is ready to be scraped off.
Slowly take your wood scraper and scrape off the surface with bubbles. The varnish should come off easily. If it is not coming off that means you need to keep using the heat gun.
Once you have gone all over the surface there should still be small amounts of varnish left. The heat gun and scraper will not take everything off so you are going to use a plane blade. I recommend this #5 plane brade to scrape off the remaining varnish from the wood.
Apply the plane blade 90 degrees to the surface and run it across the wood.
Once all the varnish has come off, you can start sanding it down from 60 grit all the way to 150 grit.
Use citrus strip
Citrus strip is a liquid solution that you can apply to your wood. You can buy it here. It’s inexpensive and doesn’t leave any bad odors or fumes. It removes multiple layers of varnish and stain so if you want to remove the varnish, I would look at something else.
Before applying the citrus strip, you want to make sure you are at least wearing gloves. The instructions say to wear goggles for extra precaution. I don’t usually do this but it does provide protection from the liquid splashing into your eyes so you should wear them to avoid any splashes.
Step 1. Shake the bottle really well. It’s good to do this to even everything out.
Step 2. You want to pour the liquid in some type of container. It will help you drip your brush into the liquid when applying. Don’t try pouring the liquid directly from the bottle of your wood because that will cause a mess.
Step 3. To get started, apply the citrus strip with a brush. Apply it like you would apply a varnish or stain. Let it sit there for a period of time.
Step 4. After applying it to the wood, you will start to notice the solution bubbling. This process can occur 15 to 20 minutes after applying the solution. Some people like to leave it on for up to 24 hours. I usually don’t do this but if you do make sure to cover the area with plastic, as per instructions. The longer you leave it on, the more varnish and stain it’s going to remove.
Step 5. Once you are ready to remove the varnish, you can use a wood scraper to slowly scrape off the varnish. There are several types of scrapers but I like this scraper that you can find online or at most home improvement stores.
Step 6. You want to first test out a location on the wood before scraping. That way you know if you are ready to scrape the wood.
Step 7. Then slowly run your scraper across the wood surface. You will want to have some type of cloth or paper towel to wipe off the scrape every time you run it across the wood.
Step 8. You will notice the varnish coming off as a sticky paste. That is normal and means you are doing it right.
Step 9. Once you get off all of the varnish, you want to take a steel wool and mineral spirits and wipe down the wood surface with them. This process will remove any of the varnish that didn’t come off with the wood scraper.
Step 10 Have a paper towel or cloth around because the liquid will spill.
Step 11. Observe the wood and see if you missed any spot. You can go over those spots again but repeat the steps discussed above.
Step 12. Once everything looks clean and the varnish has come off you are now ready to apply your new coat of varnish or stain.
One thing to note is that citrus strips can also remove the stain on the wood.
Using sandpaper to remove varnish
This method requires a bit of work if you don’t want to use an orbital sander, more effort than the previous two methods discussed. But if done right it can be a great way to remove varnish without dealing with chemicals and a heat gun.
You can start at 60 or 80 grit if you also want to remove the stain on the wood. But for varnish I would start with 150 sandpaper. Here the brand of sandpaper I use. It works great.
You can use an orbital sander to get this done. It will require less effort and will be more precise. Here is the orbital sander that I’ve been using for a long time.
Otherwise you can use a sanding block but be mindful that this will take a lot of effort.
How do you sand it down? It’s pretty simple, sand with the grain and never go against the grain as that can scratch the wood.
If you want to be precise, I would use a pencil to mark down the wood before sanding. When you start sanding, you will want to remove the pencil marks before moving on to the next grit.
To do this take a pencil and mark lines across the wood. You don’t to press too hard, enough to see the pencil mark. Then start sanding. Once you’ve been able to sand down all the pencil marks you are ready to move to the next grit which would be 220.
Using denatured alcohol to remove varnish
A lot of wood working people like to use denatured alcohol to remove varnish. It can work for certain types of varnishes.
Denatured alcohol is great for removing shellac. It also works great with varnishes but it is going to take a little longer. If you are using lacquer however it’s not going to remove it and you will want to use something like a citrus strip.
I would go with this denatured alcohol as it seems to work well for most projects and I haven’t had any issues with it.
You can apply the alcohol with a brush on the wood. Once you apply it, let it sit for a few minutes then start scrubbing it with a steel wool.
Why use a heat gun and knife?
A heat gun and knife is an easy way to remove varnish, as long as you are doing it right. I like that you can get started right away and don’t have to prepare the solution. It works instantly unlike a solution where you might need to wait 15-20 minutes or even longer.
I also like using a heat gun because it tends to get most of the varnish off in a clean and precise manner.
Now it will require you to have the right tools like a heat gun and knife. And it isn’t always perfect. You might need to run a planing blade over it as mentioned above.
There is also the risk of injuring yourself with the heat gun. You never want to point the gun on your skin as that can injure you.
Why use a solution like citrus strip?
It’s easy to apply and doesn’t require a tool like a heat gun. It can also cost less than a heat gun method as the solution tends to be cheaper.
You also don’t run the risk of injuring yourself like with a heat gun.
But with that said, using citrus strip can sometimes not come out perfect and it will require you going over the surface again with the solution.
The citrus strip also requires you to wait for some time to get the solution working. Generally it can take 15 to 20 minutes to see the bubbles but sometimes it can take longer.
Oven cleaner: spray the oven cleaner on the wood surface. Then use a wet rag to clean off the wood. This method doesn’t do as good of a job as sanding or scraping. You want to use a few coats of oven cleaner to get everything. Oven cleaners are not good for veneer so avoid them if you have furniture with veneer wood.