Click this link to view: https://youtu.be/uLA8ODqtOtU If pattern tracing pin or lens tracing pin can't move up when frame tracing operating, probably the butterfly assy broken. This video show how it being replaced.
Lens edger refurbishment available. Please do not hesitate to contact us if you need further information. Click link below to view: https://youtu.be/jm27Mtq-H_c