The machine has rust and mildew in use, and we need to clean it. Usually, there are two kinds of cleaning methods:

One is the mechanical cleaning method, namely shovel, scrape, brush and other methods of cleaning;

Second, chemical cleaning method, that is, a variety of chemical decontamination solvent cleaning.

The specific cleaning method should be handled according to the different conditions of different parts.

The following points should be noted for rust removal and cleaning of steel parts:

Do not have a high level of precision or rust removing by mechanical method is not easy to remove all steel components, can derusting with chemical method, such as concentration of 2-25% of phosphoric acid soaking for cleaning parts, soak the heating to 40 ~ 80 ℃ advisable, after being rust free, its surface can form a layer of protective film, and then remove the parts soaked in concentration of 0.5 ~ 2% phosphoric acid solution for about an hour, finally take out to dry. Improper operation of this chemical method in the factory will damage the parts, especially the precision parts. Therefore, in the maintenance of the sewing machine, rust should not be multi-purpose chemical methods, and should use mechanical rust method, namely the first use of shovel, pick, scrape and other ways on the parts of the rust layer block removed, then use sandpaper sanding, polishing, finally coated with a protective layer.