Bought this Mir on Ebay for about $9; the lens Industar 50, f/3.5 is one of the 12 junk lenses I bought for about $2 each. The lens was full of muck mis-aligned adorned with creeping fungus. Had to do a complete disassembly and CLA; re-aligned it by trial and error to get it to focus to Infinity. The Mir body was said to be working. Only the Range finder was functional. All others were out of kilter. Took me 3 days to clean. The timings were still off the mark. Opened up and found that some one had tried to add more speeds by cutting grooves in the speed selector’s brass wheel. They had also set the dial to refer those grooves. Cleaned and greased this and reset the dial alignment. The curtains springs were wound up really taught. After some flush cleaning with petrol [gas] and lubrication I reduced the tension. It worked better until I closed the bottom. Found that the shutter damper at the bottom was rubbing against the cover plate. This seems a common occurrence with old Zorkis and Mirs; because some previous owner or seller has lost the spacer [usually made of brass] that keeps the cover plate away from the damper. The clearance is only about 1mm. I cut out a new spacer from a plastic tube and set the tolerance to level. Everything started working. It took a couple of days of dry runs for the curtain springs to ease up. They may not have been used for long years. I made some test shots this morning and evening.