Staining pine woodworking projects is something almost every woodworker either has done or will do. Pine is such a lovely material to work with, it's easy on the tools, reasonably priced and available almost everywhere. If you have worked with pine you will probably agree one of the challenges of the wood is finishing it, particularly staining it.
One of the problems with Pine is that if often will not take stain evenly. When this happens it looks like the woodworker either made a mistake or didn't know what they were doing, which is not the case. The reason Pine often produces a mottled look when staining is characteristic of the wood itself. Here's the problem … often new wood is mixed with old wood when gluing boards together, and even within some boards there can be “figure” which means the grain structure changes direction or density. All of these problems manifest themselves in how the wood absorbs stain – hence mottling very often occurs.
Sadly it doesn't matter how much you sand or with what grits, there is nothing you can do mechanically to overcome this problem. It a factor of the wood, and because Pine is such a light colored wood it shows up more readily. But there is hope and there are solutions.
One of the easiest solutions comes from our friends a MINWAX in the form of their “Pre-Stain” product, which is a wood conditioner. What this product does is condition the wood to take stains more evenly. MINWAX Pre-Stain is available in both water based and oil based products. We found that while the water based product is designed to minimize grain being raised through the use of water, there still is some grain raising which means you will need to lightly sand after the pre-stain has been applied and is dry. 
We did find with some woods we worked with that two coats of pre-stain was needed. We also discovered that when we used the pre-stain products, that the depth of stain was noticeably less. That is, the darkness of the stain we were looking for was subdued somewhat, obviously by the pre-stain.
All in all we were happy with the finished results. The project we were working on showed insignificant amounts of stain blotching, that most others would not notice, so if you are working with Pine, try pre-staining to get nice even staining.
Copyright Colin Knecht
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