Signing: Time, year, season and name of maker, name of qin, occasion, whatever the author wishes could be written inside the qin, once its closed, no one knows its there. The color of the words are Titanium white mixed with lacquer to have this slightly milky brown color.
The inside of the qin has been painted a coat of lacquer w turpentine mixture to protect the wood. 1 part lacquer + 2 parts turpentine.
Detail: use many metal clasp, presses, rubber ties, binding the assembly of wood pieces tightly to prevent air holes, buckling, gaps.
Squeeze tightly until you see lacquer oozing out from joints.