Choosing the right sandpaper for the job

Without decent sanding, any paint imperfections will be far more obvious when the final coat of paint is applied.

When it comes to your paint project, it can be tempting to rush in and get that fresh new Resene colour straight on the walls. But without proper preparation, your project could end up looking more slapdash than super flash.

Builder Chris Donnelly says putting in the mahi before you crack open your Resene paint tins is essential to achieving a nice smooth finish – and sanding is a step you simply can’t afford to skip. Sanding will ensure any imperfections are removed, which will create a high-quality final look, while also ensuring your paint adheres well to the surface.

Using the correct sandpaper can make all the difference but choosing between the various types can be challenging. So how do we know which one is best for our job?

The nitty gritty

Sandpaper is rated numerically according to the size of the grit particles. The lower the number, the coarser the grit, and the higher the number, the finer the grit.

Chris recommends an 80 grit sandpaper should be used for clearing away excess material, such as old flaking paint or varnish. He says a sanding block will not only make the job easier but will ensure your sanding surface is flatter.

For larger exterior areas such as weatherboards, Chris suggests using a 150 grit sandpaper. For interior jobs that need only a light sand, opt for 220 to 240 grit sandpaper.

Make sure you choose the right sandpaper grit for your task. The lower the number, the coarser the grit, and the higher the number, the finer the grit.

Sanding poles and electric sanders make tackling large areas like walls and ceilings much easier. These require sanding discs, which also come in a range of grit levels.

And for bigger jobs, such as large areas outdoors, consider a power sander. “These are easy to use and get the job done quickly and efficiently.” For some projects you will use more than one grade of sandpaper. You might need an 80 grit sandpaper to remove old flaking paint, and then a 150 grit sandpaper to smooth the surface ready for painting.

While sanding might not be the most exciting part of your project, don’t be tempted to rush this part of the process. Without proper sanding, imperfections will be magnified when the final coat of paint is applied.

“Putting in the work with sanding will reward you with a high-quality finish at the end,” says Chris.

Wipe off

Remember to always wipe off all sanding dust with a clean cloth. If you leave sanding dust on the surface, the new paint will stick to the dust, not the surface you are painting. This will make it difficult for your paint to adhere properly and could lead to flaking paint later.