8MM-16MM FORUM WORLDWIDE

Hey guys,

What is the best way to clean a very dirty lens from an old machine that has not been used in quite some time? Also is it possible to take an Eumig lens apart for cleaning inside?

Use 70% denatured alcohol on the coated lenses themselves. Alcohol will not damage the scratch resistant coating or discolor it. If the inside of the optics are dirty, the lens can be taken apart with a tool that looks like snap-ring pliars. Not sure what it's called or where to find it but it looks like a split screwdriver with interchanable tips for flat or point bits. A lot of small format lenses are sealed from intrusion in the front by a sticker listing the F-stop and zoom (If applical) properties of the lens. You will have to pry this out of the lens to get to the actual screw holding the glass lens in place. The screw on the front looks like a big O ring with either flat spaces or holes that you will have to unscrew to remove. They are fixed in position though so when you reassemble the lens everything should fit in place.
Also, cleaning the back of the lens should really not be required since they are usually hermatically sealed on the inside even on cheap projectors. You should just clean the outside or exposed surfaces of the lens.

If you want to disassemble the lens, be VERY careful. It is easy to chip or scratch an interior element, or assemble with a element at a skew affecting focal point. Also, keep in mind that as Erik said, most lenses are sealed, or at least assembled in a clean room and sealed as best as they could, if the lens is very old.

If you really want to do it, micro-tools is your friend:

http://www.micro-tools.com/store/Search ... oryCode=30

You can find anything you could need for lens and optical repair there.

Good luck,
Michael

Thanks friends for the advice and info.