Hi Bob. Chances are high that the escapement still isn't completely clean, or some parts (likely the pivots, not the pallet faces) are worn excessively. Please note that although Prontor repair manuals specify no oil, they do specify grease on some of the sliding surfaces. I know of no known best practice that involves dunking shutter parts in either graphite or moly-d. Some knowlegable repairmen might lightly brush (and brush off) such lubricants from shutter blades, though. In some instances it seems to work but might be a "hack"; I've not seen that as a factory-recommended practice but it might be useful given the age and wear on a shutter. From what I know, the lead in pencils is graphite in clay, at varying compositions to form the varying hardness. Not exactly desireable sounding to me, at least, for lubrication purposes. I've not seen "ingredients" on the art graphite powder... maybe it's pure; IDK, though. Good luck with your repair!