Rust needs three things: bare steel, moisture and time. Remove the rust, keep the moisture off and you've won. How hard the first part is depends on how far the rust has got.
Step 1: work out what you're dealing with
Surface rust is the orange bloom that appears on a tool left in a damp shed. It wipes off on your finger and hasn't eaten into the metal. This is easy to fix.
Heavy rust is flaky, scaly and leaves pits when you remove it. The steel underneath has been lost. You can still save the tool, but it needs more work.
Removing surface rust
- Wipe off loose dirt and grease. For oily, grimy tools, cold degreaser clears the way.
- Spray the rusty area with Ballistol and leave it for 15 minutes. It creeps under the rust and loosens it.
- Rub with 0000 wire wool, a brass brush or a scouring pad. Brass is softer than steel, so it won't scratch polished surfaces.
- Wipe clean with a rag and check. Repeat on any stubborn patches.
- Finish with a thin coat of oil and leave it on.
Removing heavy rust
Oil won't dissolve thick rust; nothing you wipe on will. Be honest with yourself about this and use the right tool:
- Wire wheel or flap disc on a drill or grinder for large, flat areas. Wear eye protection.
- A soak in a dedicated rust remover or white vinegar overnight for small tools with lots of nooks. Rinse, dry immediately and oil straight away, because freshly stripped steel flash-rusts within an hour.
- Sandpaper (start at 120 grit, finish at 400) for chisels and plane irons.
Once the rust is off, treat it exactly as above: clean, dry, oil.
Keeping rust away
This is the part that matters. A thin film of Ballistol neutralises the acidic sweat from your hands and keeps moisture off the steel. Wipe tools after use, especially on damp days. Store them in a dry place, off concrete floors, and avoid sealed plastic boxes in a cold garage, which trap condensation. For long-term storage, more on rust protection.
