#0007: Restoring metal tools

Otto

#0007: Restoring metal tools

side by side picture of a pair of mini-nippers before and after cleaning.

A little while ago I received a bunch of tools for free from a friend, due to them downsizing their home. Unfortunately these tools were stored improperly and suffered weathering damage as a result. They were essentially stored in a puddle, in a bucket, in a leaky shed. Basically leaving everything rusted to one degree or another.

I took the loot home and sorted the good from the bad. And just as I was about to discard the rest; the sheer volume of rusty crap gave me pause. I wondered as to how much of it I could actually save and refurbish to a useable state. However, I should also mention that I was largely unwilling to actually spend any money on this project. I wanted to see what I could do with the tools and resources I have on hand. Consequently I used household sundries like vinegar instead of a rust remover product, and would’ve used some-kind of random household oil (such as cooking oil or bicycle lubricant) instead of WD40 to loosen any seized tools if I didn’t already have it to hand.

example of rust remover product
picture of 5 litre jug of evaporust branded rust remover product

Okay, let jump in. These are the tools and materials I used:

Tools:
    - plastic container
    - wire brush
    - (ball point) hammer
Consumables:
    - water
    - vinegar
    - WD40
PPE:
    - safety glasses
    - thick gloves
    - apron

It’s a nice small list. So there is little in the way of barriers to entry. Meaning that the strength of this method is that it allows people with very limited resources to simply add salvaged tools to their resource pool whenever they find them, and consequently increase their effectiveness.

picture depicting a collection of tools. A wire brush, a spray can of WD40, and a pair of thick gloves.
picture depicting a blue plastic tub and a bottle of inexpensive vinegar.

Basic Method:

I created an acid bath by mixing water and vinegar in a 1:1 ratio into a (barely) large enough container. Added the tools and waited a couple of days (7+) for the acid to fully react with the rust until the solution formed a thick brown foam on it’s surface. Then removed the items from the bath and scrubbed them down with the wire brush until all traces of rust has been removed.

After which, I finished each item off by it wiping dry with a rag. Then wetting it with another rag laced with WD40, and working the solution into the tools’ various crevices to help expunge any traces of moisture and to provide some protection against any further corrosion.

  • picture depicting an acid bath with tools submerged within it. A large amount of caramel coloured foam has formed on the solution's surface.
  • picture depicting the plastic acid bath tub after the submerged tools have bben removed from it.
  • picture depicting a rusted pair of garden shears with it's blades half covered in the caramel coloured foam from the vinegar bath.

Notable specifics:

Acid Bath:

The reason why I use an acid bath is to react with and consequently remove the the rust. Rust is a form of iron-oxide compound; the acid reacts with the oxygen in the compound and breaks it as a result. Any residual rust left over after the submerging period will in all likelihood be structurally compromised (softened up) and consequently easier to remove manually with a wire brush.

The reason why I use vinegar is because: one; as mentioned above, I didn’t want to spend money and vinegar was a readily available household sundry; and two, vinegar is a very weak (and consequently safe) acid that will return good results if left to work for a long enough time period. I submerged the tools in it for more than a week before I worked on them. Had I used a stronger acid (such as phosphoric acid) or a product (such as evaporust) I would’ve been done within the day and would not in all probability have to work on the tools with a wire brush.

However by successfully using vinegar, it illustrates that it can be done at little cost. Funnily enough it also adheres to that old adage “you can have it done fast and cheaply, but not good; cheap and good, but not fast; or good and fast, but not cheap.” Vinegar would be the second option in that adage.

Additionally, vinegar is such a weak acid that the chances of it damaging the good metal underneath the rust is said to be minimal. Hence less care and attention is needed with it’s application. However having said that, it seems that vinegar does indeed remove material from the tools (as can be seen within the photograph of the partially dipped shears). Whether or not it started to eat away at ‘healthy’ metal or simply removed a thick layer of rust (including the patina) is hard to tell. What I can say definitively is that more material is lost from the tool in the process of using an acid bath over just scrubbing with a wire-brush.

As a final note on this, a good way to immerse items that are perhaps a little too big for the tub you have on hand; is by using rags to wet the areas of tools that are above the waterline. You don’t even have to dip the area below the water level. As long as the rag touches the solution; the capillary effect of the cloth will draw up the liquid towards the areas of the metal that you have wrapped the rag around. Using wet rags is also a good way to avoid a case that requires using voluminous amounts of solution to fill up a big enough container to submerge large or awkwardly shaped items.

example of rags used in an acid bath
  • picture depicting a screwdriver and a large drill bit wrapped in rags.
  • picture depicting a rag wrapped metal tool in an acid bath. The rag is wicking the vinegar up and around the parts of the tool that are above the water level.
  • picture depicting a rag wrapped metal tool in an acid bath. The rag is wicking the vinegar up and around the parts of the tool that are above the water level.
  • picture depicting a rag wrapped metal tool in an acid bath. The rag is wicking the vinegar up and around the parts of the tool that are above the water level.
  • picture depicting a rag wrapped metal tool in an acid bath. The rag is wicking the vinegar up and around the parts of the tool that are above the water level.
  • picture depicting an acid bath with tools submerged within it. A caramel coloured foam has formed on the solution's surface.
screwdriver before and after
  • picture depicting a flat head screwdriver pitted with surface rust
  • picture depicting a flat head screwdriver pitted with surface rust (close up on the rust)
  • picture depicting a flat head screwdriver's shiny yet pitted metal finish after a clean
  • picture depicting a flat head screwdriver's shiny yet pitted metal finish after a clean (close up)
  • picture depicting a flat head screwdriver's shiny yet pitted metal finish after a clean (close up)
comparison between bathed and scrubbed metal and just scrubbed metal
  • picture depicting a rusted pair of garden shears with it's blades half covered in the caramel coloured foam from the vinegar bath.
  • picture depicting a garden shear the has been partially cleaned. The shear's blades have been cleaned and brushed only halfway to illustrate the difference between clean and rusted.
  • picture depicting a medium close up of a garden shear's blade that has been partially cleaned. The shear's blades have been cleaned and brushed only halfway to illustrate the difference between clean and rusted.
  • picture depicting a close up of a garden shear's blade that has been partially cleaned. The shear's blades have been cleaned and brushed only halfway to illustrate the difference between clean and rusted.
  • picture depicting a very close up of a garden shear's blade that has been partially cleaned. The shear's blades have been cleaned and brushed only halfway to illustrate the difference between clean and rusted. Two layers of metal removed can be seen.

Mini end nippers:

Anything with a seized mechanism such as the pictured mini end-nippers; required WD40 to be applied and allowed to soak into the joints of the mechanism. After allowing it to soak in, I worked the handles again and again until the joints started moving. I continued this until the rust inside the mechanism was macerated by the WD40, and worked out by the repeating opening and closing of the joint.

A hammer might be needed to apply sudden force to either the tool’s (let’s say pliers) jaws, handle, or the joint mechanism itself to loosen it up in the case of a strong seizure. I used a ball point hammer to help localise the hit just to the specific joint without pointlessly impacting the frame of the tool. A hammer punch will also be very effective in directing and localising applied force. Sharpening the nipper’s jaws with a file is also recommended as a final touch.

washed and scrubbed but mechanism still seized
  • picture depicting a close up on a rusted pair of mini end nippers
  • picture depicting a rusted pair of mini end nippers inhand
  • picture depicting a rusted pair of mini end nippers covered in the caramel coloured foam from the vinegar bath
  • picture depicting a close up of a rusted pair of mini end nippers covered in the caramel coloured foam from the vinegar bath
  • picture depicting a close up on a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism looks seized closed.
  • picture depicting a close up on a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism looks seized closed.
  • picture depicting a close up on a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism looks seized closed.
mechanism lubricated and made operable
  • picture depicting a disassembled and partially cleaned pair of mini end nippers
  • picture depicting a partially assembled clean pair of mini end nippers
  • picture depicting a pair of mini end nippers with a ball point hammer next to it
  • picture depicting a close up on the mechanism of the mini end nippers. A lot of debris wet with WD40 has been worked out of it.
  • picture depicting a close up on the underside of the mechanism of the mini end nippers. A lot of debris wet with WD40 has been worked out of it.
  • picture depicting a close up on the underside of a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism looks loose and functional.
  • picture depicting a close up on a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism is loose and functional.
  • picture depicting a close up on a cleaned pair of mini end nippers, its very pitted yet shiny. The jaw mechanism is loose and functional.
  • picture depicting a cleaned and assembled pair of mini end nippers

Drill bits:

With these I found that holding the brush in the left hand and scrubbing with (i.e. in the same direction as) the thread is the best way to get deep into the bits valleys and remove the rust as efficiently as possible. After the bits are cleaned, they also need to be sharpened with either a small file or some kind of specialised bit sharpener.

complete before and after comparison
  • picture depicting a collection of drill bits for comparison. Half of them are fully cleaned and brushed and the other half are in their original rusted condition.
  • picture depicting a close up on a collection of drill bits for comparison. Half of them are fully cleaned and brushed and the other half are in their original rusted condition.
drill bits after acid bath, before scrubbing and oiling
  • picture depicting a collection of drill bits post acid bath but prior to wire brushing.
  • picture depicting a close up on a collection of drill bits post acid bath but prior to wire brushing.
after scrubbing and oiling
  • picture depicting a close up on a collection of cleaned and oiled drill bits.
  • picture depicting a collection of cleaned and oiled drill bits.
  • picture depicting a collection of cleaned and oiled drill bits.

Personal Protective Equipment:

This is something that is often overlooked by people, however I do think that personal safety is something that people should take into account on any and all projects. Well, as long as you don’t go overboard to the point of the sometimes overbearing British “Elf and Safety” silliness. I have seen people on job-sites with overbearing rules go the complete opposite direction as a form of rebellion as soon as the manager is out of sight. Discarding basic things like gloves and eyewear in the process. Its sad honestly.

I am getting off topic. In this case, the apron keeps the rust vinegar mix off of your clothes as you brush down the items (if you care); and more importantly the safety glasses keep that stuff from flicking into you eyes in a moment of inattention. That’s probably the main reason why I wear these things for everything from soldering to this. Its because I am aware that my attention ebbs and flows as I perform tasks, I am not always in the moment 100% and that’s when accidents happen.

So for me at least. Safety glasses are a must, I don’t want to take any chances with my sight. However everything else is largely optional. I also added gloves to protect the hand that is holding down the workpiece from the wire brush. I put these on to allow me to work quickly and effectively.

The point is, there needs to be a mindful reason as to why and when (and when not) to use PPE in projects, even mundane ones such as this.

References, Sources, Further reading:

https://en.wikipedia.org/wiki/Iron_oxide
https://en.wikipedia.org/wiki/Rust
https://en.wikipedia.org/wiki/Patina
Geoffrey Croker – Rust Removal Methods Explained [https://www.youtube.com/watch?v=Qi-tK1jwO-k]
Slavscribe – How to remove rust? Acid vs. Bolt | AcidTube-Chemical reactions [https://www.youtube.com/watch?v=k9OYNPCnLNs]