Wanted to CLA my Compur, it's the old style with the cardboard aperture blades. Self timer, 1 and 2 are a little slow, the timer itself takes minutes to actuate the shutter. How do I clean do I just brush isopropyl alchohol around it or something? I heard you cant submerge them in alcohol because of the aperture but this one I can remove the aperture assembly completely so would it still be safe?