I have been making some furniture and finishing floors lately. The home-boss (wife) has her heart set on dark stain colors for most anything I make. Thus I tend to leave the stain a bit thick. Not excessively so but enought to make it darker than what you would obtain if you wiped the stained surface with lots’ of pressure. I am a big fan of wiping varnishes and oil-varnish blends for top-coating. However I have found that the oil-based stains will lift/streak when I apply the first top-coat. If I were to just brush on varnish with no subsequent wiping, then everything is fine (as it is for the 25 zillion other people that have done this). But wiping wants to rub off any excess stain.
I have recently resorted to laying down one layer of zinsser seal-coat as a barrier and then top-coating. Of course this works just fine. My question is this: Is the shellac (or other system) typically required? I am not adverse to using it, but I am trying to eliminate steps when possible.
I have no intention of changing bases for most of my work, so please avoid the advise about using water-based top-coats or stains, etc. This is an oil-on-oil question. I am familiar with water and alcohol stains and have used them with success.
Replies
You don't say whether you are applying a pigment stain or a dye stain but, I am assuming it is a pigment. The pigment in pigment stains stay of the surface of the wood, rather than being completely absorbed into the wood as is the case with dye stains.
If you put pigment stain on heavily and do not wipe it off as the label instructs, you will have more pigment on the surface but it will not be firmly adhered. Brushing or wiping will be aggressive enough to cause the weak binder holding the stain on the wood to be overcome and some of the pigment is re-dissolved and is left on the brush or rag. You are then smearing this redissolved pigment around on the surface.
The way around this is generally to spray a 1# or less cut of shellac to more firmly adhere the pigment to the surface. Then you can brush or wipe your finish coat. You can generally get away with lightly brushing on a coat of shellac. As long as you don't do a lot of back and forth brushing, you should be OK.
So, to answer your question, if you leave a heavy coat of stain on the wood you will have to use a seal coat unless you have the ability to spray on a finish. You can try to use a very thinned first coat of varnish and very light and quick application with your wiping rag and see if it works. As long as the first coat gets on, it will seal the pigment and subsequent coats should be OK.
mlbfreestyle,
Using shellac as a barrier between two products that might/will interact is one of the classic uses of shellac. As you've discovered, using an oil-based stain, and then trying to wipe on any other oil based product, can lift and streak the stain. A coat of shellac between them will solve the problem.
Using shellac between them, you can use different colored stains to create some great looking effects. It's a way to emphasize different colors without having the two stains mix and turn to mud. Using different color shellacs can add another color layer. On oak I like to use dark sienna and golden oak stains with a thin coat of garnet shellac between them, and then a coat of orange shellac between the golden oak stain and the varnish. It's easy to do and IMHO looks great.
Alan
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