Introduction: Introduction to Wood Staining
Wood stain has a lovely effect of enhancing the appearance of the wood by embracing the lovely grain pattern and making it pop with a change in colour unlike paint, which covers it up. I’m building a set of bookcases at the moment and have been experimenting with a variety of effects. These experiments are on the cheap white soft wood available from most big box stores (which could be spruce, fir, pine or other).
I am not a carpenter or cabinet maker, just an experimental hobbyist. These instructions are a guide but I encourage you to try your own sample experiments from start to finish before going for the real thing. Stain is really hard to remove entirely.
Step 1: Applying Commercial Wood Stain
Wood stain is a thin, coloured liquid that penetrates the surface of wood and marks it that colour. Readily available for about $8.00 in a 1 quart can. Sand the wood with 180 grit paper until it is smooth and clean the dust off. Apply the stain by dabbing a lint-free cloth into the stain and rubbing it in or use a natural bristle brush to apply thin layers which you wipe the excess off after 5-15 minutes. Always try to work with the grain. Good long and definite strokes, don't tickle the wood.
Natural brushes are not that expensive; 69 cents for a 2” brush from Harbor Freight or a whole box of 36 for $10.95. I prefer using an old cotton t-shirt cut into 4”x8” pieces that I fold into a stack and hold with a binder clip. The material is cheap, soaks up stain well and the rounded edge minimises brush marks whilst keeping my hands clean holding the clip.
Step 2: Mixing Stains for Custom Colours
When you don’t find a colour of stain you like, you can mix them together quite happily like paint. I tried using Minwax Polyshades which boasts a stain and a polyurethane topcoat all in one application. I bought 1 quart of the Bombay Mahogany for $12.00 hoping for a deep dark tone with a pop of red. It states that one coat is sufficient and another is okay for a deeper colour. One coat was much too light and no good. Coats 2, 3 and 4 made it darker but nowhere near the shop sample on pine.
I mixed some ebony stain into the Bombay mahogany in varying ratios (settling on 1:5) for a darker stain but still with some red and the benefit of a topcoat. It is hard to salvage stained wood as you have to sand a decent layer off to get to where the stain has not penetrated. In a vain attempt, I sanded the surface down along the grain with 80 grit, which was successful in revealing the bare summerwood and less of the springwood. I used these "sanding screens" from Harbor Freight which are quite good at $0.99 for 20 sheets which fit my sander, and they're double sided. The lattice layout prevents clogging of the sheet.
Once cleaned up, I wiped on some of my stain mix with a folded rag to produce a personally pleasing weathered or burnt effect. It made the wood grain more vibrant and is how the rest of the bookcase will be treated. I also took a plane to the edges to create a chamfer showing the original wood as a line around the edge for a bit of definition.
Step 3: Dealing With End Grain
On solid wood boards, the end grain is the side at the end of the board where you can see the growth rings, i.e. when you see a tree stump, that whole surface is end grain. End grain absorbs stain better than the other faces because of the wood structure. The pores of the wood suck the stain down further into the wood and make it appear much darker than the face.
One way to deal with it is to “burnish” the end grain which requires sanding to a higher grit than the face and making the pores effectively smaller. You would sand it all to say, 180 grit, but on the ends continue to 220 grit, 320 grit and maybe even 400-600 grit if you’re determined. This makes the ends very smooth and limits the depth at which stain is absorbed thus maintaining colour shade. This is detailed in the next step.
Another way is to sand the end as normal and apply a “glue size” which is a mix of carpenter’s glue / PVA and water in a 1 part glue : 10 parts water. Brush the mix on to wet the entire end and let it dry out fully for a couple of hours then sand the end with 180 to remove that layer of glue mix from the surface. The glue mix left only in the pores will inhibit the stain and give a more even colour.
Step 4: When Have You Sanded Enough?
Sanding end grain is time consuming as it is naturally quite rough. After the initial 80 grit sanding it may feel as smooth as the rest of the board but the stain will tell a different story. The key is to watch for that layer of lighter coloured sawdust to disappear. Sanding with 80, 120 and 180 grit can still produce peaks and valleys on the end which are filled with the sanding dust; these are the light areas you want to get rid of. Going up to 220 and finally 320, the surface is clear or any lighter scratches and is relatively flat. It will also feel beautifully smooth to the touch. Now you are ready.
Step 5: Alternative Staining Mixtures
There are a host of alternative wood stains you can use with varying success including black coffee / tea, crushed berries and nut shells. Vinegar and steel wool is a great mix that adds great age to new wood in an ebonising effect.
Put on some protective gloves and take a roll of 0000# extra fine steel wire wool under a hot tap to wash off any rust-inhibiting oils. Make sure it is actually wire wool in the packet as I am aware there are some imitations that will not work. Pull the steel wool apart into a thin layer and place in a glass jar. Pour over ordinary white vinegar until the wool is covered. Cider vinegar is also an option. If you have some rusty nails, throw those in too and leave the jar with a loose lid for 24-48 hours until the bubbles have stopped and the vinegar is darker. Give the jar a shake every while / when you walk past it.
Strain the mix through a coffee filter or cloth to remove the small metal particles. Brush the mix on with a brush to leave a wet layer, a rag will not get the surface wet enough. Again, go with the grain when applying. Let the wood dry for a few hours and it will go a magnificent dark colour. Softwoods go a blue-grey, great for aging new wood. Hardwoods go darker depending on the tannin content of the wood. Mahogany and oak go very dark from this reaction.
This forum post documents different wood reactions to the vinegar mix.
The sharp smell will dissipate after a few days. The surface will also need a top coat of oil or varnish to protect it.
Step 6: Wood Stain Blotchy?
Wood is a variable material and can be unpredictable to stain resulting in blotches where the wood is of a different density. You can apply a wood conditioner which is a brush-on liquid that soaks into the wood pores and evens the stain absorption.
A different method is using Caustic Soda (Sodium Hydroxide or Lye) to oxidise the surface. In the UK, you can get caustic soda as a powder from Boots and other hardware places as a drain cleaner, about £2.50 for 500g. CAUTION: It is very dangerous stuff and causes severe burns on contact with skin, so treat it carefully with gloves and goggles in a ventilated area.
Mix one (1) teaspoon with one (1) litre of water into a spray bottle to make a dilute solution. Spray it all over the wood and it will change colour almost immediately but will dry to a more natural colour. Once dry, the grain will be a bit more exposed and most importantly even, making stain more even. In the US, caustic soda is much harder to buy and have heard that a mix of one part cheap drain cleaner with one part water achieves a similar effect, but I have not tried it.
This webpage details the caustic soda technique for aging pine.
Step 7: In Conclusion
Remember to try out a sample first before embarking on the entire process. Wood is a funny thing and like underwear, stains only makes it funnier. My bookcase will receive all the stain results I've gathered soon.