Linitop wood filler applied to a door

How to prepare wood for varnishing

If you want the finish on your wood to look its best, it’s vital to put in a bit of legwork at the beginning of your project.

You must make sure that the wood you’re intending to varnish is dry, clean and in sound condition. It must also be free of mill glaze.

Depending on the condition of your wood, you may need to remove any old varnish or stain.

Applying varnish to a wooden step

New wood

It’s important to sand new wood (grit 180) to encourage the opening of the pores.

Wood that’s already stained

You may be able to apply a varnish without removing the existing wood stain, as long as the stain is in good condition. However, you should still sand the entire surface (grit 180).

Wood covered in an old, undamaged varnish

Ensure that you remove any flaky parts and then roughen the entire surface to enable better ‘keying’.

Old varnish in a poor condition

If the varnish is cracked or flaking, you must make the wood bare by sanding or stripping the entire surface.

At this point, many people reach for a sander. Although sanding can be effective, it can also be extremely hard work and very dusty. In addition, you could find that you end up sanding away more of the wood than necessary.

For those who don’t fancy covering themselves (and their surroundings) in a fine layer of dust, it is possible to prepare a wooden surface with a stripper.

Using a multi-purpose stripper

DSP800 packaging

Owatrol’s DSP 800 Stripper is a powerful, ‘Dichloromethane’ free multi-purpose stripper, suitable for removing of a wide range of coatings, including acrylic, epoxy and cellulose.

Fast acting and ready to use, DSP 800 leaves a clean, coating-free surface that can be refinished after only 6 hours. Even better, as it contains no acid, caustic soda or potash, it will not darken wood and therefore requires no neutralisation after use.

This stripper is ideal for a wide variety of projects, as it can be used on both interior and exterior wood surfaces. Additionally, it can remove car paint, get rid of unwanted carpet glue and strip paint from stone and cement walls.

Before using DSP 800 on your whole project, it’s important to apply it to a small test area. Full instructions for use can be found here.

Get rid of those small surface imperfections

Linitop grain filler being applied to a wooden door

Before applying your top coat of varnish, you could fill these imperfections with a transparent grain filler. The Linitop Grain Filler can even be applied to old varnish that is in good condition.

It’s important to note that you shouldn’t apply grain filler to bare wood. You’ll need a coat of varnish first.

When it comes to preparing your wood, there’s no need to reach straight for the sand paper. On some occasions, it may be possible to strip your wood with a multi-purpose stripper instead and save yourself both time and effort.


If you have any handy tips or advice, please feel free to leave them in the comments below.

We love hearing from you! If you share your project on Twitter, Facebook, Instagram or Pinterest please feel free to tag us @owatrolUK or use #owatrolUK so we can see and share your hard work!

How to prepare wood for varnishing - Pinterest

Owatrol Team
About Owatrol Team

Our team are ready and willing to support you with your requirements whether it is protecting your newly laid deck or renovating a luxury yacht, whatever the application Owatrol has the solution you are looking for.

Leave a Reply

Your email address will not be published. Required fields are marked *