Introduction: From Trash to Treasure a Vintage Chinois
I have been looking for a Chinois for some time now, not knowing its name and only knowing it on sight made it impossible to order on line. Chimois are not a standard item for canning supplies in most of the stores where I live and this made it even harder to get one when all I could do was describe what I wanted. Now that I have one I finally know its name.
The vintage 3 piece Chinois I finally found came with a cone colander, a stand, and a wood pestle. The steel was tinned at one time, however with time and use the tinning was hidden by rust. If I want to use this Chinois for canning I am going to have to get it thoroughly cleaned.
The Chinois has so many nooks and crannies scrubbing it clean with a wire brush or sand paper would just destroy it and was out of the question, I was going to have to clean the rust electrolytically with baking soda.
Step 1: Electrolytic Rust Removal Supplies
Most people electrolytically remove rust using washing soda, (Sodium Carbonate). It is an effective and relatively safe method for removing rust. I am going to electrolytically remove the rust using baking soda, (Sodium Bicarbonate) since I couldn’t find washing soda.
Baking Soda (Sodium Bicarbonate)
Battery Charger or a car battery.
Small Scrub Brush
Clean Steel or Iron electrode, I used three steel rods I salvaged from printers for the anode.
Wire to connect the steel rods together and hold them in place I used stainless steel wire.
A Plastic Container, large enough to submerge the Chinois I am cleaning, I used a 5 gallon (18 L) water bottle.
You can clean a part with some of it sticking above the solution and then rotating it to clean the rest, however it may leave marks on the metal.
Step 2: Electrolytic Rust Removal
Electrolytic rust removal is a very simple way of removing rust without damaging the underlying material. Basically you submerging the rusty metal in a solution of washing soda or baking soda and apply a current to it and a sacrificial piece of steel.
Attach the positive lead from the battery charger is connected to a sacrificial piece of steel, (Anode). And the negative lead from the battery charger to the object you want to clean the rust off, (Cathode). Make sure the anode and the cathode do not touch. Add your cleaning solution. When the battery charger is turned on a reaction occurs between the anode and the cathode. This loosens the rust so it may be easily washed off. This technique doesn’t appear to damage the metal under the rust in any way.
Important Safety Precautions
The cleaning solution is alkaline and will irritate your skin and your eyes. Always use eye protection and rubber gloves when working with the solution and rinse off any spills. The battery charger must be shielded from the cleaning solution. The leads from the charger are relatively safe but you can still get a shock if you put your hands in the cleaning solution or touch the electrodes while the power is on. Turn off the power to the battery charger before you touch any of the parts. Work in a well ventilated area the water will break down into its components, hydrogen and oxygen and this can combust with just a spark.
Step 3: The Procedure
First prepare your container I used a 5 gallon (18 L) water bottle with the top cut off.
To the sides of the container I attached 3 steel rods evenly spaced and wired them together with stainless steel wire. I did this to clean the parts evenly.
Next I attached a piece of wire to the first part I wanted to clean and placed it in the container making sure it didn’t touch the steel rods.
In a separate container I mixed 1 table spoon of baking soda to 1 gallon of water. Mix the solution until all the baking soda is dissolved.
Add the solution to the container until the part being cleaned is completely covered with the solution.
Attach the positive lead from the battery charger to the steel rods, and the negative lead from the battery charger to the part you are cleaning the rust off.
Turn on the battery charger if everything is right the charger should register charging and little bubbles of hydrogen and oxygen should be on the steel.
Step 4: Notes for Trouble Shooting
If the the battery chargers meter register over current or a short the steel rods and the part you are cleaning are touching or they are too close together. There is a number of things you can do to reduce the current.
Increase the distance between the part and the steel rods.
Dilute the solution by adding more water.
If you have a 6 and 12 volt battery charger set it to the 6 volt setting.
Now you just have to wait, the time needed to clean a part varies on size of the part, current, and how badly rusted the part is.
After an hour the current on the battery charger dropped, and there was scum on the surface of the water. I turned off the battery charger and removed the part from the solution. Where the rust was it was now coated with a black sludge.
Step 5: Wash the Parts
Using dish soap and a small nylon brush I cleaned off the black sludge rinsed and dried the colander and stand.
If it looks like you took the piece out too soon simply put it back in the cleaning solution and start over.
Once the piece is finished it will be a gray color. I liked the gray color on my vintage Chinois however if this finish isn’t acceptable to you, use a wire brush to remove the gray oxide coating.
Last make sure the piece is dry so that it won't start rusting again and put some sort of rust inhibitor, wax, or oil coating on the parts.
Step 6: NOTES
Good plating should not be affected by this process however if the plating is loose it may flake off.
This cleaning process can soften some paints. Remove any wooden parts before cleaning.
This cleaning process depends on electrical contact for cleaning. If you are cleaning a item with multiple parts make sure all the parts have a electrical contact with the negative lead of the charger.
There is a chance that metal cleaned this way may be subject to hydrogen embrittlement. This can happen in processes like welding or electroplating. This should not be a problem unless you are cleaning hardened steel. If you are cleaning an item made of hardened steel and you intend to use the item rather than simply displaying it you may want to try baking the part in an oven from 300°F to 440°F (150°C to 225°C) for several hours. This can neutralize the hydrogen embrittlement.
Participated in the
Trash to Treasure Contest