It is not difficult to clean flat or cylindrical metal parts, for example, using a drill and a wire disc. When the parts have a complex shape (usually they are obtained by casting), it is better to use the electrochemical cleaning method, which proceeds automatically, does not require large costs and time. True, such work should be carried out outdoors or in a well-ventilated area.
It will take
Materials and tools:
- old rusted part;
- soda ash or baking soda;
- galvanized bucket with water;
- a piece of plastic pipe and wire;
- welding machine;
- container for washing the part;
- drill with a disc nozzle, etc.
The process of electrochemical cleaning of metal parts in a garage
For clarity, we will clean the old automobile brake caliper from dirt and rust with a rather intricate shape, although any other part can be in its place.
We take a metal bucket with clean water as an anode, add baking soda or soda ash and mix intensively. The result is an electrolyte.
To a plastic tube laid across the bucket from above, we hang the part to be cleaned, which acts as a cathode, on a wire so that it does not touch the bottom and side surface of the bucket.
We connect the plus to the bucket, and the minus of the welding machine to the part to be cleaned, after turning on which the electrolyte will begin to boil and heat up from the mass movement of ions in the electrolyte between the electrodes.
The current produced by the welding machine can be any. With its low value, the electrolyte heats up slowly, as does the process of cleaning the part. With an increase in the current strength, the processes are intensified. We select the average current value – 120 A, then the first stage of cleaning will last about an hour, and the electrolyte will heat up to 70-80 degrees Celsius.
After the specified time, the results of electrochemical cleaning are evident. All dirt from dust, tar and grease floats to the top in the form of brown foam, and rust particles settle on the surface of the bucket.
We turn off the device, disconnect the terminals and pull the part out of the electrolyte. It can be seen that the caliper cleaned well. A certain amount of rust remained under a layer of paint, which is easily removed with a knife, and in hard-to-reach places.
We remove paint residues and other contaminants with a stiff brush in a container with warm water and washing powder. After such a wash, the part was cleaned by 85-90 percent.
We repeat the one-hour process of electrochemical cleaning, replacing the old contaminated electrolyte with a new one, and washing in soapy water using a brush. Moreover, according to the nature of the electrochemical process, the rust from the caliper (cathode) passed to the surface of the bucket (anode). The part is now almost 100 percent clean.
We unscrew the bolts, other removable elements, opening places where the electrolyte has not penetrated. We repeat the process of electrochemical cleaning for the third time, but already for 30 minutes. Similarly, we clean the caliper bracket. The final operation is polishing with a drill and a circle.