Every mechanic and tradesman has had to deal with rust on their tools. Often it happens from leaving them out at night or not cleaning them before you put them away.
Depending on the tool you might actually ruin it past repair if it gets rusty. If you leave any precision tool like a torque wrench or micrometer out without cleaning it or place it in a tool box that has moisture in it you might as well just toss it.
Other tools like a hammer or hand saw can get pretty rusty and still survive.
Why did your tools get rusty?
This should be the first question you ask yourself. If you are going to go through all the work of cleaning up your tools you don’t want to be doing it again regularly.
Where were your tools left? In a toolbox in the back of your trunk or truck? Do you store your tools in a shed over winter or maybe in a damp basement?
Moisture is the primary reason for rust however anyone that has worked in drywall or masonry knows that not cleaning your tools completely every day will result in rust from the caustic drywall compound or portland cement acting on the metal. This is why some tools are made of magnesium or aluminum but that is no excuse for not cleaning your tools every day.
Even battery acid from a flashlight battery can destroy your tools and that is good reason to never leave batteries in your test equipment unless you use them every day. At least pull the battery and put it in a ziplock bag and off to the side.
Find the reason and cure the reason.
Whats the best way to Clean Rusty Tools
This will depend on the tool. If you are cleaning up garden tools like shovels or hoes then you can use a wire brush… actually sometimes if the rust is just on the working area you can just use the tool for a day and the abrasion of the soil will take most of the rust off.
If they are in real bad condition then you will need to wire brush or even sand blast them.
Smaller hand tools can be cleaned with a Brass Brush rather then a steel one. Brass will not destroy the steel because it is softer. It will take more work but it is safer especially on tools like socket wrenches, pliers or small screw drivers.
Once you have got as much free rust off that you can and the tool seems bright you want to wash the surface with a metal prep liquid. Don’t do this on the head of socket wrenches only treat large areas like handles and shovel heads.
When the surface is clean you will need to coat it so it won’t rust again.
For hand tools or something like a circular saw you can use engine enamel that is much better then standard $1 synthetic enamel in a can.
For shovels and hoes and garden tools like hedge trimmers you want to use a spray oil like WD40. However even a old rag with used motor oil from your lawn mower can be used to lightly wipe the surface and allow you to store the item for winter.
If you have hand tools for masonry or drywall you will need to keep your tools clean and dry. You should not apply paint or oil on the working surfaces because it could cause problems while working.
Just washing and wiping down your tools every day at the end of the day will keep them in good condition. If you are using your tools a lot then they should not rust. If you need to store your tools in a damp area then make sure they are sealed well and you might be able to pickup some desiccant bags like you find in clothes sometimes and place your tools in a sealed bag.
Also if you are working with powered tools any internal rust will mean you need to rebuild the tool. It could mean replacement or cutting of an armature or replacement of bearings..
The less intricate the tool the better your results will be but if the tool has deep pits and it is inexpensive then replace it or clean it up and carry it as a second or backup.