Ultrasonic cleaning for lenses?

[Drew Bedo]

Anyone ever use an ultrasonic cleaner to clean up an antique brass lesn? I mean just the brass parts, noty the glass.

What danger is there for separation is a cemented group is put in with dish soap as a solution?

[domaz]

I would kind of worry about putting in an old cemented group underwater. It probably won't come uncemented but water might get in between the elements and then you would have to uncement it to get it out. I've always just cleaned up old glass with typical lens cleaners but be very careful not to get solvents on the balsam.

[Eric Woodbury]

I worked for a group that made hermetic glass sealed pins for transmitting electrical signals into a vacuum. These were formed in a drilled hole through a special alloy of stainless steel. They were small, so that would have some effect. We tried cleaning the part once in a sonic cleaner. It crazed (produce a network of fine cracks) every pin, shattering the glass and losing the seal. I would not put brittle material in a sonic cleaner.