Sanding White Pine: Avoiding A Sticky Situation
I love, love, love Eastern White Pine. First of all, I love the way it smells – it can make even the nastiest of shops smell like new. I love the way it cuts –it cuts great on the sawmill and in the shop. I love that it’s lightweight – even, the widest boards are easy to handle. I love that is dries flat – most boards can just be run through the planer without any flattening. I love that it is soft – I can work it with hand tools and enjoy every minute of it. I love that when it starts to decay it gets lots of bugholes and blue-stain – it’s great for rustic work. I love that it makes great planer shavings – I want to roll in them just like the animals that use it for bedding.
There is, however, one major problem with white pine, especially air-dried white pine. It’s name is pitch. Pitch is the sticky transparent yellow goo that can ooze from the boards. In lumber that has been kiln-dried at high temperatures to “set the pitch”, this is less of a problem. As long as the lumber stays cooler than the temperature that the kiln was run at, the pitch will remain hard. But, once that threshold is passed, the wood starts to get sticky. And, since air-dried lumber hasn’t reached a very high temperature in its life, the stickiness is almost immediate.
Now, couple this setup with a large job and large boards and a lot of surface to cover with a power sander and you have a recipe for potential disaster. In fact, some air-dried white pine will be so sticky that you’ll start to wonder if there is enough sandpaper in the world to get through the job. There is, of course, a secret to working with white pine and an orbital sander. The secret is turpentine or mineral spirits.
I read somewhere that turpentine is made from pine trees, and I figured if it came from pine trees, it should be a great solvent for pine pitch, which also happens to come from pine trees – and it is. A rag dampened with either turpentine or mineral spirits will clean the pitch right off of a sanding disc or off of lumber where it has built up. To make it work in an almost automatic mode, I keep a sacrificial rag next to me soaked in the solvent and simply run the sander on the rag when it gets clogged. Just a few seconds running the sander on the rag makes the sandpaper look like new.
As I now get ready to sand a project that is all white pine, with wide boards and big, pitchy knots, I know the first thing I will do is get out the mineral spirits. Hopefully, this lumber cooperates and I won’t need to use it. Happy sanding to all!
For fun, I have some photos of the wide white pine (up to 20″) being used for shelves that inspired this post.