I found a rusted old toolbox on the side of the road, and decided it deserved a second chance. After consulting with a hardware store employee I gave it a scrub with a wire brush and steel wool, unbend the dented edges, vacuumed it off, and repainted it. The whole process took under 10 hours total, including shopping for supplies.

You may want to fix up a toolbox too. Either for yourself or a friend that wants one, or to donate it. Either way, you're turning something that would've ended up trash into a useful thing, while teaching yourself a little bit about rustproofing.

After finishing the toolbox, I asked myself what I would want out of an Instructable before starting this project:

it should be self contained, you shouldn't need to google things
it should be be flexible enough to handle many kinds of toolboxes

I have done my best to provide the above in this walkthrough.

This Instructable was prepared as a project for the Fall 2018 offering of INTEG 375: Hands-on Sustainability, a third-year course in the Knowledge Integration program at the University of Waterloo.

Step 1: Find and Assess a Toolbox

Look wherever trash, junk or debris is to be legally found. I picked mine up from a curb where it was left for free, but you could check junkyards (with permission), Goods Exchange Day (if that sort of thing happens near you), or other kinds of goods exchange services like eBay, Kijiji, etc.

As for the condition of the toolbox, you should ensure that it's all together, sturdy and the hinges are aligned. Steel wool and grease can help rusty hinges, but bent or mangled hinges may make the toolbox un-salvageable.

My toolbox was missing the removable rack, but these can be easily made or bought.

Fixing missing/broken latches or patching holes in the metal (larger than pinpricks that would be filled in by paint) is possible but falls outside the scope of this Instructable.

Step 2: Gather Supplies and Equipment

For this project you will need the following, all available at your local hardware store:

Safety glasses
Pocket knife
Green painter's tape
Clothes for paint that will never come out
a pair of needle-nosed pliers, and/or slip joint pliers
a thick wire brush, for most of your rust-scrubbing
a piece of medium-thickness steel wool, for scrubbing the spots the wire brush can't reach (corners, etc.)
about 5 disposable foam paintbrushes, as big as can fit into the paint container
half a pint of oil-based, pre-coloured rust paint. May be called 'alkyd-based' instead of 'oil-based'

Tip: Ask your hardware store employees for help! If you explain what your project is, they are generally more than happy to offer advice, especially in picking a suitable paint.

Optional but highly recommended:

a basic dust mask (breathing rust isn't harmful short-term, but irritates lungs)
work gloves, something to stop the rust and steel wool from irritating the skin on your hands

Step 3: Find a Place to Work

Ideally, you'd have access to your own workshop/makerspace with a fume hood
where you can prop the toolbox up and leave it to dry. As a student at the University of Waterloo, I found a tucked-away workshop that let me take up a spray booth for a week.

If these kinds of resources are not accessible to you, I would strongly recommend finding a makerspace using The Maker Map.

What you're looking for in a makerspace is use of an industrial vacuum (like a Shop-Vac), and helpful people at the makerspace that are comfortable giving advice on this sort of project. You could use a home vacuum to gather the loose rust and steel wool, but I'm not liable to any damage this could cause your vacuum.

If the makerspace doesn't support leaving the toolbox there to dry for a day after every painting session, the toolbox can be brought home and painted in a well-ventilated area unlikely to be disturbed.

Step 4: Straighten Out the Toolbox

Use your pair(s) of pliers to adjust any out-of-place warps or bends on the
closing edges of the toolbox. Repeatedly test the hinges to make sure the toolbox can open and close without resistance. Check the interior of the toolbox to make sure any metal sticking out is aligned and bend them back if not.

Now that you've bent the edges of the toolbox back, test that the latch still engages without resistance. It often doesn't, because the latch and toolbox edges bent together. Straighten the latches so they re-engage without resistance.

Step 5: Scrub the Toolbox

For the toolbox, the goal of scrubbing is not to completely remove the rust.
The goal is to remove all rust not firmly attached to the toolbox, as we want the paint to only bond to well-attached rust.

Now is an excellent time to wear your safety glasses, and your work gloves and dust mask if you have them.

You may find a combination of semi-packed dirt and rust coating the bottom of your toolbox. Use your pocket knife to scrape off as much as possible. Shake your open toolbox over a trashcan if necessary.

If the hinges are stiff and rusty, start there first by using the wire brush. Avoid scrubbing the hinges with steel wool as it is liable to leave small steel filaments in the hinges. They will irritate your hands if touched, they risk bonding with the paint, and could jam up the hinges.

Once the hinges are finished, use the wire brush everywhere and the steel wool everywhere the steel wool can't reach. Be sure to also scrub over any remaining paint, as rust can occasionally bubble up from under paint.

Periodically vacuum up the combination of rust, paint and loose steel wool using an industrial vacuum. Once you're done scrubbing rust off, give the toolbox a final vacuuming, inside and out.

Step 6: Prep the Toolbox

All this scrubbing has possibly bent your toolbox again! Recheck that the toolbox still closes, and latches shut easily to make sure everything is still aligned.

I messed up on my own toolbox, and got paint on the handle and latch. In the interest of you learning from my mistakes, I'd highly suggest wrapping your handle and latch pieces in green painter's tape.

Step 7: Paint It

If you've never used oil paint or foam brushes, please note that oil paint doesn't come out of clothes, stay on hands , and foam brushes hold lots of paint but releases only when scraped against an edge.

Unfortunately, it's impossible to paint this toolbox in one session without resting the drying toolbox on something. My solution was to paint the toolbox over multiple days and have it rest on a dry side, with about 24 hours in between for the oil-based paint to dry.

Each painting session, I made the edges where I stopped painting the natural edges of the toolbox: where the metal comes to a sharp edge on the outside of the toolbox, and the edges where the lid meets the main body. As all toolboxes are shaped slightly differently, there is no universal answer to this. After painting a side, wait a few minutes to make sure the paint won't run when you turn the toolbox.

Important: do not get paint on the hinges. This almost guarantees the hinges will bind, especially if the paint dries in one position. If you manage to splatter paint on them (like me), wiping it off with a dry paper towel should be enough.

You may find it useful to prop up your toolbox while it dries, to keep paint with edges on it off your working surface (and on your toolbox). After using your disposable paintbrush for the day, throw it in the garbage. Unfortunately,

Step 8: Find Your Toolbox a Home

If you fixed this toolbox up for yourself or someone you know, congratulations! You can skip this step or read on if you're interested.

Access to tools (and their storage vessels) promotes tangible creativity, personal growth, and an understanding of the constructed world around us.

Please consider donating to a makerspace like those found on The Maker Map. Alternatively, an Internet search of "donate tools [your region]" could show charities interested in giving your tools new life.

Happy fixing!