To Prime or Not To Prime
When painting furniture, prep is vital for a good foundation, leading to a professional finish that not only looks good, but will last.
There is no single solution for all projects. The type of paint you’re using and the type of substrate (base material) you’re painting must be taken into consideration, therefore, every project must be assessed individually.
Prep is the important and grotty job that very few of us enjoy, however minimal. Some paint brands advertise no prep, but that really is not ideal. I always compare it to wearing make-up. Would you put fresh make-up on over yesterday’s foundation?
The simplest form of prep is to degrease your item of furniture with Fusion’s TSP or Methylated Spirits, scuff sand (120 grit sandpaper is usually enough), wipe clean and start painting. This option is possible with a paint brand that has a built in primer like Fusion. Every brand is different though, so you must check the guidelines of the one you’re using or better still use Fusion, of course.
OK, so why can’t you just paint straight onto any surface if you’re using Fusion then? This brings us back to evaulating the substrate which will determine if priming is required.
Where Fusion is concerned, you can paint over multiple surfaces (varnish, paint and bare timber) thanks to it’s resin formula, making it good for adhesion and self sealing. Waxed surfaces must have the waxed removed first though with White Spirits. The exception to bare timber are those that bleed. Although Fusion will adhere no problem, tannins will stain your paintwork leaving it looking discoloured in places and stained. However, if using dark colours, this tends not to be an issue.
Problematic woods are: pine, knots, oak, red woods like mahogany and cherry and teak.
- Water based primers - used for adhesion purposes only and is not a stain blocker. These are often white in colour and low VOC. Fusion have their own version - Ultra Grip - which goes on milky white and dries clear. This can be particularly useful if you want to do a little distressing on your furniture at the end without having any white primer showing through. Ultra Grip is required under Fusion for adhesion to glossy surfaces like glass, melamine, laminate, plastic, shiny mahogany furniture, metal etc. It can be scuff sanded when dry. It is touch dry in approx 30-60 mins. Recommended recoat time is 12 hours. It’s suitable for exterior projects. Virtually odourless and with zero VOCs. Warm, soapy water clean up. Highly suitable for painters with sensitivity to chemicals and odours.
- Oil based primers (ie. Zinsser Cover Stain*) - used to block the likes of tannins, smoke or fire damage, mildew, water stains etc. Don’t use your favourite brushes on this, just a decent but cheap one and clean up with White Spirits. It’s a bit on the thick side, so try to apply thinly. Once dry you can lightly scuff sand for a smooth base before painting. Touch dry in 30-60 mins. Recommended recoat in 2 hours. Cure time 4-7 days. It’s suitable for exterior projects. May not be suitable for those sensitive to chemical odours.
- Shellac based primers (ie. Zinsser BIN*) can do everything that the oil based primer does and more, such as sealing odours, knots, rust and crayon. These days it can be regularly recommended for all priming, even though it may not be required. It is a very good product, but not cheap and not the easiest to use. Unlike the Cover Stain this is quite thin and watery and must be stirred well. It dries very quickly too. Again, don’t use your good brushes and clean up is with Methylated Spirits (purple). It dries in about 20-30 mins and the recommended recoat time is 1 hour. Cure time 1-3 days. This primer should NOT be used on exterior projects. May not be suitable for those sensitive to chemical odours.
You can use a brush or mini roller to apply all of the primers mentioned. Keep your washable Two Fussy Blokes rollers and when they’re getting too worn for painting, use them on the oil and/or shellac primers then bin them.
Once you’ve established your substrate and what you need to do to ensure a professional finish, you’re ready to go.
Also, please bear in mind that not all knots or tannins appear immediately. It can take hours, months and even years for these nasties to appear if you have not primed correctly.
If you are painting for yourself then sometimes taking a chance for ease and speed is tempting (we've all done it), but if you are painting for a customer, do it right, do it once and your reputation will soar.
I hope that you've found this blog educational and you're welcome to leave comments. If you have any questions, please don’t hesitate to get in touch.
Thanks for stopping by.
* This blog is in no way affiliated with Zinsser and their products are for reference purposes only, as this is my brand of choice.