| Author | Message | ||
     Scott Tinkerer Username: Scott Post Number: 145 Registered: 07-2006 Rating: N/A |
So, your middle and front element casings came out stuck together? You just have to try various ways of separating them. Main thing is to resist the urge to use vise-grips, channel-locks, etc. The brass is too soft. First step is to get them apart. Then remove the glass lens elements from the lens casings, clean the old grease, corrosion, and crud off the brass parts, then clean and replace the glass, then put new grease on the focus threads. I have been able to solve this problem in most cases, but not all. One of the things it can depend upon is what type of grease was used. Not all solvents work on all sorts of grease. Some I tried soaking in naptha first, but no result. Then what eventually worked for me was the strongest alcohol I could find, which is pink and sold for industrial cleaning purposes in both Taiwan and Sweden. I'm not sure what the equivalent is in North America. Maybe denatured alcohol is good. Or pure ethyl alcohol if you can find it. With a needle or a wire-brush, remove as much crud as you can off of the threads, then submerge the stuck parts for a couple of days or a week or more. Another thing that has worked for me in some cases is to heat the parts in an oven to about 250 degrees F, then while they are still hot, grasp them with gloves or towels and unscrew them. That's faster, so try that first. Keep it at 250 degrees for at least 15 minutes, to heat it evenly and to soften the grease well. That shouldn't damage any coatings, and those may not even be coated lenses. Solvents such as alcohol and naptha won't damage lenses or coatings. |