Woodcraft of Harrisburg
3831 Union Deposit Road
Harrisburg, PA 17109
Hours of Operation
|sunday||12PM - 5PM|
|monday||9AM - 7PM|
|tuesday||9AM - 5PM|
|wednesday||9AM - 5PM|
|thursday||9AM - 7PM|
|friday||9AM - 7PM|
|saturday||9AM - 6PM|
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Pre-conditioners: When and Why to Use One
After spending a long time making the perfect project, the next step is applying the perfect finish. In the past, I’ve struggled with applying my stain and then noticing a very uneven and blotchy result, appropriately called “blotching.” This happens more with woods like pine, cherry, maple, poplar, and birch which have spongy areas that soak up more liquid (and therefore more color) than other areas.
Blotched (left) Pre-conditioned (right)
Before applying a stain, these types of woods need to be pre-conditioned, a process that slightly fills the pores in the wood, but still allows some stain penetration. All pre-conditioners will lighten the stain color, but will also make it more consistent. There are several different types and styles of pre-conditioners. One I like to use is a washcoat- take any finish, thin it down, and apply. I typically use Zinsser’s SealCoat, a two pound cut of wax-free shellac thinned one-to-one with denatured alcohol. I’ve also found adding a little more denatured alcohol can give me better color retention.
Pre-mixed pre-conditioner examples
Pre-mixed pre-conditioners are also available, notably from General Finishes (water and oil based) and GoodFilla. Be sure to follow the instructions for how long to wait before applying the stain. A final option is to use a gel stain without any pre-conditioner. The pigments in a gel stain lie on the surface and consequently aren’t affected by the grain of the wood. Above all, do not use a sanding sealer at full strength- the pores will be completely filled and the stain will not take at all. I’ve found the GoodFilla to be the best overall product. The General Finishes options have better color retention, but less blotch control while the SealCoat has good blotch control, but lower color retention. Depending on the project, each has it’s place.
Finally, all is not lost if a stain blotches and resanding is not an option. Apply one coat of the desired top coat finish, let it dry, sand lightly, and then apply a matching color gel stain as a glaze. Let the gel sit for three or four minutes, wipe off the excess, dry, then apply two more layers of top coat. Not perfect, but the process can save a project.