Using Vinegar & Salt
Courtesy of Richard Boughton
Demonstration on a Plane
This method appeared in the 1990 bulletin of the Society of Ornamental Turners:
- Soak item in a plastic, glass or enameled tray in a quart of vinegar mixed with two tablespoons of salt. This makes a dilute solution of hydrochloric acid strong enough to lift off the rust but harmless on hands and clothes. For light rust, soak for a day, for heavy rust, two or three days.
- Remove and rinse in warm water and detergent. Most of the rust will come off with a rag. Scour rest with steel wool.
- Finish by wiping with an oily rag or spray with WD-40.
- The solution can be re-used by adding a little salt. When it becomes very dirty, throw it out and start over. Keep a lid on it to prevent evaporation.
Click for larger images
After treatment the rust dissolved easily with a toothbrush and scourer. The plane iron, the worst bit, had a bad patch that needed scraping with a chisel, but it probably would have dissolved if it had been left soaking for longer. The plated parts came up pretty well. The plane started rusting immediately, which happens whatever method you use, so it was given a rub with linseed oil.
This is a cheap, easy and effective method of rust removal.
- smells like a chip shop
- possibly causes slight brown staining (might have been a reaction with the nickel plating)
- The vinegar was the cheapest possible malt. Perhaps distilled vinegar would be better
Using Vinegar & Salt Compared with Evaporust/Metal Rescue
Demonstration on Rusty Tools
Courtesy of Claire and Richard
The following experiments were conducted to see how the vinegar solution, being cheap to use, compared with results from Evaporust/Metal Rescue. Metal Rescue is exported by the manufacturer in concentrated form and is diluted locally before sale by the distributor, making it cheaper than importing ready-diluted Evaporust.
- In the red box the cheapest distilled vinegar and table salt were mixed (a mere 33p for the vinegar), using the above method.
- In the clear box Metal Rescue/Evaporust was used. As can be seen, some items were on top of others and touching, but all were submerged.
- The boxes were covered to prevent too much evaporation and left for about 24 hours. After this time the colour of the vinegar solution looked the same, but the Metal Rescue/Evaporust had turned black. A couple of parts were given extra soaking (hence missing items from some pictures).
- After use the liquids were poured back into bottles.
- The items were rinsed under running water and scrubbed with a kitchen scourer to rub off the blackened gunge. After drying they were lightly rubbed over with a diluted mixture of linseed oil to prevent further rusting. Whichever method is used something must be rubbed over to protect from future deterioration.
In conclusion, both methods worked pretty much the same and the results were certainly comparable. Both were very easy to handle and simple to wash off.
Neither mixture appeared to be better than the other.