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.
Never SAND White Pine! Plane it by hand and leave it!
Thanks for the quick comment Marty. I agree. If you can plane it by hand do it. However, on this job there is about 200 bd. ft. that needs to be surfaced on two sides. No go on the hand planing. Most of it is in good shape out of the planer, but there are a few spots that require some love. Hand planing is especially good on the rustic work. Set the plane deep and leave the marks.
Pine is iconic. People know what it looks like. It’s one of the few woods that everyone under the sun knows the name smell and look of. They associate pine with cabins, hunting, grandmas house. Even if pine can be sanded, why waste your time? The first set of keys that hit the table or riveted jeans sit on the chair, you a right back into rustic-ville. Save the sanding for Cherry, Walnut and Maple. Building furniture that needs to be sanded out of Pine is a mis-application of material.
I agree almost completely. Material consideration is an important part of the building process and pine does lend itself to more simple and even rustic work. But, I think it is a little too aggressive to say that it should never be sanded and that if you sand it you are not using it correctly. In many cases, the edges are eased and made to look more worn by sanding (sandpaper) and burnishing (hammer handle), which is difficult to achieve with a straight-cutting tool like a hand plane. In this project specifically, some of the boards, since they were wide, ran through an area of the thickness planer that had knicks in the knives. Without a little sanding, I felt that the final project would look more amateur. The key here is that I know some woodworkers will be tempted or forced to sand pine at some time and may face the issue of clogging sandpaper. Hopefully, this will help them avoid having to buy extra paper. Thanks for the spirited discussion!
Great Blog Scott!
Kerosene works well and is heavily use in industrial applications to deal with pine pitch. It can be cheaper than paint thinner and is less likely to catch fire I believe.