Cleaning flat or cylindrical metal parts is not difficult at all, for example, using a drill and a wire disk. When parts have a complex shape (usually they are produced by casting), it is better to use an electrochemical cleaning method, which occurs automatically and does not require much expense and time. True, such work should be carried out outdoors or in a well-ventilated area.
Will need
Materials and tools:
- old rusty 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 disk attachment, etc.
The process of electrochemical cleaning of metal parts in a garage
For clarity, let’s clean an old car brake caliper with a rather intricate shape from dirt and rust, although there could be any other part in its place.
We take a metal bucket with clean water as an anode, add baking soda or soda ash and mix vigorously. As a result, we obtain an electrolyte.
We hang the part to be cleaned, which acts as a cathode, from a plastic tube laid across the bucket from above 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 to the part to be cleaned, after turning on the welding machine, the electrolyte will begin to boil and heat up due to the massive movement of ions in the electrolyte between the electrodes.
The current produced by the welding machine can be any. When its value is low, the electrolyte heats up slowly, as does the process of cleaning the part. As the current increases, the processes intensify. 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 obvious. All dirt from dust, resins and grease will float to the top in the form of brown foam, and rust particles will settle on the surface of the bucket.
We turn off the device, disconnect the terminals and remove the part from the electrolyte. It can be seen that the caliper has cleaned well. Some rust remains under the paint layer, which can be easily removed with a knife, and in hard-to-reach places.
We remove paint residues and other contaminants using a stiff brush in a container with warm water and washing powder. After such a wash, the part was 85-90 percent clean.
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, rust from the caliper (cathode) transferred to the surface of the bucket (anode).The part is now almost 100 percent clean.
We unscrew the bolts and other removable elements, opening the places where the electrolyte has not penetrated. We repeat the electrochemical cleaning process a third time, but for 30 minutes. Clean the caliper bracket in the same way. The final operation is polishing using a drill and a wheel.
