1. remove the screw head, check, thrust ring.
2. a brass brush to remove the screw on the resin residues, waste cloth wipe away the residue of the melt
3. check screw surface conditions, if there are minor scratches can fine gauze gently polishing, if there are scars, then the reasons should be identified and repaired.
4. screw after cooling to room temperature, and wipe away using nonflammable traces of oil on the screw.
5. clean the screw in the same way the head, check, thrust ring.