Q&A OF THE WEEK: “How Can I Stop Tools From Rusting In An Unheated Work Space?”

Q: How well do woodworking tools survive in an unheated Canadian workshop? I’m mainly concerned about rust. The few tools I stored in unheated spaces this past winter have developed rust. What can I do to stop this?

Tools stored in unheated garages and sheds will attract condensation and rust during cold seasons unless you take steps to stop it. Prevention includes storing small tools in sealed, wooden boxes, or protecting large ones with paste wax, oil or spray-on grease. The hazard is greatest in spring time as warmer air moves in while tools are still very cold.

A: Unheated work spaces in places with cold climates often cause tools to rust, but there are ways to stop or minimize this trouble. The biggest danger happens in spring when we get warm air moving in suddenly after a cold spell. The tools are still cold from that deep-freeze the night before, but the springtime air today is warm and carries lots of moisture. If this warm air is allowed to come in contact with cold steel, it triggers condensation on the surface and rust. Preventing warmer air from touching colder tools is key to preventing tool rust.

One solution is to build a wooden tool box to store smaller tools in. This is what I did when I had to work in unheated spaces for years before I built my heated workshop. The box is as big as half a phone booth and the lid fits fairly tightly. Inside I keep a moisture-grabbing bag like the one below that keeps tools dry between uses and rust-free. The wood of the box acts as a kind of insulator and it absorbs moisture as well as does the bag.

Moisture Grabbers are one powerful option for reducing the humidity around tools stored in unheated spaces. The more moisture you can pull out of the air where tools are stored, the less likely rust is to develop.

All this is fine for small tools that can fit in a box, but a tablesaw, planer or other stationary tools can’t. In this case the best approach is to choose stationary power tools that have minimal cast iron or other rustable surfaces. Regularly wiping a thin coat of oil on surfaces that can rust is about the best you can do but it works. Only use the tiniest bit of oil. A couple of drops per square foot of surface area is all you need.