As furniture painters, not only do we want to make sure that we are as eco-friendly as possible on our upcycling projects, but we also want to make sure that we create perfectly finished furniture pieces (with as less hassle as possible!). Primers aren’t the most eco of products – so only use them if you really have to.
To make sure have beautifully finished products, we don’t like to cut corners! But what if I told you that we might actually be doing more harm to our work by not understanding our priming products properly.
There is so much confusion between all of the different primers and the different reasons to prime! Here are my quick tips on when exactly you should use primer.
There are only two reasons you should ever prime your furniture.
1. To help cover up wood grain & knots and to prevent bleed-through.
2. To provide a surface which ensures that paint will bind to it.
… there are two types of primers that assist these reasons.
1. Let’s start with our first reason to prime. Bleed-through.
Bleed-through only really occurs when you are painting a dark piece of furniture into a light colour. This big colour transition sometimes (not always!) can tint your paint colour with an off-pink or yellow. The woods that you should be concerned about are cherry, mahogany, knotty pine or newer softwoods.
You will never have to worry about bleed-through when painting in dark colours – as it simply wont show through.
How can you prevent bleed through?
Simply by swiping your paint on an inconspicuous part of your furniture with your finger as a test. This is a trick that was shown to me by Sarah Pelley, and is something that I would always recommend doing as it’s a great way to eliminate an unnecessary coat to your furniture. If your paint has turned pink or yellow after 10/15 minutes of your swipe test, then you know your wood is having a bad effect on the paint. In which case you will definitely need to prime.
(Please note, this tip is not 1000% infallible. If in any doubt then prime your furniture.)
What primer should you use for bleed through?
The only primer that I would recommend for completely blocking bleed-through is the Zinsser B-I-N Shellac. To prevent bleed-through it must contain shellac because if you use a water-based primer it’s actually like having another coat of paint.
(Strange fact:- Did you know that Shellac is made from insect poo !)
I like using the Zinsser B-I-N spray on pine, as you can focus on the knots by spraying on those areas and blending in the product slightly. When you start to see a yellow colour change, you know that is starting to bring out the bleed. Spray on another coat of this product and sand around the edges afterwards so that it isn’t noticeable once the paint is applied.
Prep for this primer is the same as always, still make sure to thoroughly clean your piece, and scuff sand it.
2. Our second reason to prime is for adhesion purposes.
Although Zinsser B-I-N does have some adhesion properties to it, if you are looking to paint something that is shiny like plastic, glass or metal then you need an actual adhesion primer.
What primer should you use for adhesion purposes?
Fusion have one called Ultra Grip, they also call this product their bonding agent. Whitson’s Superior Adhesion Primer is another quality primer that I recommend.
Fusion’s primer contains a lot of resin in it, which is what is used in paint to make it stick and go hard. Their Ultra Grip primer is white in the bottle but it dries clear. When applying this primer, watch out for your brush strokes as you can’t always see how much has been applied, so when you start painting you can quite often find that you have left a lot of texture behind. A good way around this is to use a roller rather than a paint brush.
If the Ultra Grip starts to lace or separate during application, then it’s simply not sticking to your furniture properly which means you will need to leave it 12 hours before applying another coat. There are very few occasions when this will happen. Possible there is a factory finish silicone coating on it – if so scrub at is with white spirit and then rinse.
Cait Whitson is the distributor for Fleur, and they have developed some of their own products including Whitson’s Superior Adhesion Primer, and what’s interesting about this one is that it is white. It has a really nice finish to it and the texture emulates paint really well so you can give it a sand afterwards.
So those are the only two reasons that you will need to prime your furniture. You will never need to use both together, IT IS ONE OR THE OTHER, Shiny surfaces that need help with adhesion will never bleed and woods that bleed will not need help with making the paint stick.
The more layers you have the more problems you may fall into, and the longer your piece will take to cure. A lot of these products are pretty toxic, so only prime if you really have to, this top tip will ensure that you are as close to zero VOC paint as possible!
I hope this is useful, if so please share it on with some people!