The joint is then soldered with rosin and good soft solder, containing a sufficiency of tin. The junction is completed by means of a warm joining tool, care being taken to mix the gutta- percha well without burning. As soon as this has cooled another coating of Chatterton's compound is spread over the gutta- percha, taking care not to burn the compound. Then, while it and the Chatterton coated joint are still hot, it is laid on the joint, and pinched tightly round it with the finger and thumb, after which it is trimmed off close with scissors. The seam is again pinched and carefully finished off with a warm tool, so as to mix the gutta- percha of the two sides, and the coating of the wire itself, well together.
Cleanliness is essential to success.