Originally Posted by
stitch1967
My 15k80 has what looks like a brittle brown hazing over the black japanning. It is predominantly around the oiling holes. Is it an original part of the varnish/japan covering or is it just dried up oil? I would like to clean it off but do not want to do any unnecessary damage. Is it what is meant by shellac?
To be sure we would need to see a photo, but cleaning a machine with sewing machine oil is almost always safe.
Shellac is the product made from beetles that is like a modern poly coating. The older "japaned" machines are "painted" with mixture of shellac and black pigment and then baked.
Using new oil to soften and clean the old oil works very well but slow (and safe) you can use other "treatments" but they are progressively more risky to the decals.