Best way to apply stain

Question

I made a shoe-rack from Spruce and applied a couple of coats of clear matt varnish. My wife wanted a darker colour so I went to the local store where the only suitable product with the right colour was a small tin of "woodstain", the instructions on the tin said to thoroughly sand any previous varnish so the "stain" would adhere. The product is intended for outdoor use and requires 2 or 3 coats. So I guess it is more than a mere staining colourant and has some other stuff in it that produces a waterproof protective coating.

After a satisfactory test on a small chunk of wood I went ahead and lightly sanded, cleaned and then applied the stain using a paintbrush.

The results were hideously blotchy and uneven, mostly due to the fact that the stain seemed to be drying (more like coagulating) before I could brush out any drips/runs. I am now looking forward to sanding it down to plain wood and refinishing.

It is possible I applied too much "stain" at a time, or maybe conditions are not right (I brought the work indoors as my garage temperature is below the minimum on the tin).

What techniques should I try with this product?

Answer 1

I guess it is more than a mere staining colourant and has some other stuff in it that produces a waterproof protective coating.

Yes, this type of product isn't stain in the conventional meaning of the word.

This is another example of the dilution of the proper meaning of woodworking terms by manufacturers *sigh* This Ronseal product is a coloured acrylic 'varnish' and I don't know why they don't just market it as coloured varnish to save the inevitable confusion.

the stain seemed to be drying (more like coagulating) before I could brush out any drips/runs

Well it does call itself quick drying :-) Finishes are indeed coagulating in a way as they dry on a surface and if you pick up some of the part-dried finish as you brush back over previously coated areas you'll get a horrible mess as a rule.

It seemed clear to me that the product is really intended to go onto bare wood and doesn't like going on top of existing finishes. The data sheet confirmed my suspicions. I don't know how strongly this is stressed on the tin but:

"All previously applied film forming products, for example paints and varnishes, should be totally removed."

So just a light sanding was not sufficient.

Sidenote on finish removal: I would actually try to dissuade you from sanding off previous finishes as your go-to technique. Chemical strippers are usually the best way to get finish off thoroughly. If a purely physical method is a necessity for reasons of cost, toxicity or just smell then scraping is much preferable to sanding: it is faster and more efficient, always cheaper, safer for the user (much less dust) and there is less potential for accidental damage to most furniture.

What techniques should I try with this product?

• Work as smoothly and efficiently as possible using a larger rather than a smaller brush, but a foam or short-nap roller may be a better application tool.
• Try to apply the varnish and leave it alone. Resist the temptation to go back over the finish already applied after even a short time.
• Keep a clean brush or lint-free rag dampened with water on hand to deal with drips or runs on edges, don't attempt to deal with them using the application brush.

One last note if using a brush, synthetic bristles are highly recommended rather than natural bristles.

Answer 2

I would not recommend commercially available stains for anything intended to have furniture-like quality appearance, especially stain & finish one-step products. The problem with stains is that they are not really a stain, but contain pigment particles. Since the pigment particles are fairly large the deeper the color desired and/or the more coats applied, the more the wood grain is covered up.

I would suggest trying a wood dye instead. You can get Transfast wood dye powders from Woodcraft.com for about $12 for a 2 oz. bottle (makes about a gallon total). Mix it with denatured alcohol and rub it on with a rag. You can also mix it with water, but water raises the grain where alcohol doesn't. The colored granules are much smaller than those used in stains and the result is the colors are rich and the wood grain really expresses well. Just rub in the dye with a rag, but use gloves unless you want tinted hands for a couple days. Finish the wood afterwords, with a standard clear varnish, lacquer or other finish as desired.