Focus lens

[Jim Reinhard]

How fragile are the focus lenses ?I have cleand my lens many times ,From reading the way to clean them ,They act like there going to sratch or break or scratch if you even touch them with your finger.

[Mike Null]

They are not fragile but you can scratch them. Best to apply the liquid cleaner and let the dirt soak before cleaning it. I need to clean mine several times a day when cutting and engraving wood. The lens is going on 6 years old.