When it comes to preventing rust on tools, a reader asks: My husband and I store power tools, hand tools and garden tools in our garage, and they’re getting quite rusty. I’m not sure why because they never get wet. What’s causing the rust and how can we stop it?
Here’s my response.
Rust on tools stored in unheated sheds and garages is a common and constant problem, especially in climates with wide swings in temperature from summer to winter.
The worst time for tool rust is in spring, when warm weather rolls in quickly after a cold spell. The tools remain cold for a time while the air around them becomes warm and moist. This leads to frost and condensation developing on tool surfaces, just like beads of condensation build up on the outside of a cold drinking glass in the summer. As water appears on your tools out of nowhere, it triggers rust.
Options for preventing rust on tools
Your first line of defence is to store as many of your hand tools as possible in a wooden box with a sealed lid. Wood tends to absorb excess moisture, keeping it away from metal tools.
You’ll enjoy even better results if you also keep something inside the box to absorb moisture. The best I know of right now is a product called Moisture Grabbers. It comes as a cloth-type bag with moisture absorbing beads inside. Moisture Grabbers come in different sizes, some ideal for toolboxes and others large enough to dehumidify small rooms.
I’ve found I can use and reuse these bags indefinitely. When they’ve soaked up all the moisture they can, put them in a toaster oven at about 120 F (50 C) for four hours. After this the bag is effective again.
For large tools that can’t fit in a toolbox, you need to protect all rustable surfaces with a coating. The trick is to make this job as quick and easy as possible or you simply won’t do it.
Normally, I try not to use products in aerosol spray cans because they’re expensive for the amount of product they contain, but protecting tools from rust is an exception. I used to use WD-40 for this job, but it’s too thin and it evaporates too quickly.
These days I protect my tools with the same kind of rust protection I use on my truck. I buy either Rust Check or Krown in spray cans, then apply it to anything that threatens to rust. It takes just a few seconds to lightly coat most items. And even if you don’t coat everything, the liquid creeps over time to cover entire surfaces.
For keeping shovels, axes and other steel gardening tools rust-free, there’s a surprising and highly effective option. Boiled linseed oil is usually used only on wood, but a thin coat applied to steel protects it exceptionally well.
This oil oxidizes over a few days and forms a non-oily skin that protects metal for a long time. I wouldn’t apply this to, say, a table saw top since things don’t slide as easily over it. But for steel digging tools, boiled linseed oil works fabulously well. I’ve never heard of anyone else doing this, but it’s a regular practice at my place.
The video below is mostly about sharpening a scythe (a classic hand tool used to cut long grass and grain). But at the end I show how I use boiled linseed oil to protect the rust-prone blade of a scythe. It works amazingly well, with no oily residue left behind because this kind of oil hardens and forms a protective film, as you’ll see.
