If you observe how nature weathers and distresses painted surfaces, driftwood or barnboard, you’ll see that the outer layers get weathered more, and any cracks or crannies that are more protected will have less weathering.
The surfaces that are close to a handle, on the edge of a board or where it gets constant foot traffic, handling, or exposure to sun and rain will show more patina.
This can take years, even centuries to wear down the paint or the softer layers of wood and create that look of age.
In some cases, the same processes can be emulated and copied to speed up the process.
Shabby Chic, the fascinating style of country decor uses this method to make newer pieces look well loved and well used by carefully sanding the edges of a piece of painted furniture, copying the wear that would occur naturally.
You can achieve this look by sanding with fine grade sandpaper or fine steel wool to emphasize any imperfections or details.
Weathering and distressing wood are techniques that require a keen eye for observing how it happens in nature.
Don’t overdo it.
The suggestion of ancient exposed wood grain or wood beneath layers of crackled paint is enough.
To make a rustic garden sign or other craft look old, use a piece of barnboard that already has cracks and signs of weathering. Nail holes, gouges and rough areas showing how it was sawn in an old time lumber mill will only add to the patina.
First sand the board, taking off only the really shaggy and rough edges. Splinters should be pulled off or rasped smooth.
Layer your first coat of acrylic craft paint, and allow to dry.
With medium grit sandpaper or fine steel wool, carefully remove some of the paint.
This can be all over, especially if your board is really cracked, as the remaining paint will be in the deepest cracks.
Paint another layer of a different colour over top, and allow this to dry too.
A quick buffing with the sandpaper or steel wool will take off any raised grain from the paint.
Paint your lettering on the sign at this stage. What should you paint on it? How about some of these humorous garden sign sayings?
Now comes the fun part; distress the lettering, the edges of the sign and the outside edges. Using finer sandpaper or steel wool will give the best results as it looks less like scratches, and more like the weathering that happens from wind and rain exposure.
Paint the edges of the sign with a dark colour if you wish, and after that layer dries, use a tack cloth to get all the dust off, and then spray with water based Varathane.
This product is easy to clean up (water based) and gives a great protective coating.
I’ve had signs and doors out in
full exposure to weather for several years and they still look perfect.
Taking a page from the Bonsai masters book, you can use lime sulfur to age wood - be aware that the smell of this technique is awful, so only use this where you can allow the odour to dissipate naturally.
Bonsai artists use the diluted lime sulfur to paint onto 'jin' or the driftwood portions of their little trees, which gives them the silvered appearance of extreme age.