WS 22: Servicing a SEIKO 7005 including replacing the balance
This is the view of the open main spring barrel. Quite a "soup" in here.
Remember that mainsprings are often greased with a special spring grease
containing graphite. There will be a story about this spring on a later page. It
turned out that the spring even after the ultra sonic cleaning would not produce
enough torque to keep the movement going.
And I had to "kick" my pride for a second time. While the barrels I had encountered so far had a cover (right side) recessed into the barrel case, this one had actually an overlapping lid. So I called my watch tutor because the lid of the barrel would not come off using the simple method of pushing onto the barrel arbor (the center part winding the spring) while the barrel was laying upside down on the work pad.
After talking to Rob, he suggested a razor blade to continuously loosen the lid around the barrel. Before finding a razor blade, I used my thumbnail and wow, that worked. I slowly worked a gap of ca. 0.5 mm between the lid and the barrel and the cover of the barrel came of nicely.
That was the last part of the disassembly. Note that I shortcut the disassembly in two ways. First, I did not disassemble the calendar mechanism and second, I did not disassemble the automatic winding system. Please note that when looking at the parts buckets on the next page.
Please click on the last picture to read on >>>