Cleaning Eyepieces (internal)Posted By P. Lee Stock |
Jeremy,
If you have good dexterity and are good at cleaning fingerprints and smudges off lenses to your satisfaction, then taking eyepieces apart is not that daunting of a task. I did the same thing with a Speers-Waler Zoom--essentially completely disassembled it to get out all the dust.
Ease of disassembly depends on the eyepiece design--spacers and retaining rings, etc. Some lens configurations simply drop out in a single stack once a lower retaining ring is removed (Widescan II, for example). Others have internal rings holding things in place. These are harder to disassemble and reassemble. Sometimes you can only get an eyepiece partially disassembled before it becomes too difficult, but partial disassembly is sometimes enough to get to the stubborn debris to blow it out with a bulb blower or remove it with alcohol and a Q-tip.
Something that might help with some eyepieces is some kind of tool that can pull a lens carefully up and out of the barrel without having to turn the eyepiece over and let the lenses drop out, like a small suction cup--I assume these are available (and probably from Edmund Scientific Optics Division). Or you can hold a lens in place with the tip of your finger, turn the barrel over and gently drop it out if you must, though you must clean it properly (Q-tip and 99% isopropyl alcohol is what I'd use).
Another useful tool is a spanner wrench to grip the two opposing notches in a retaining ring. A tiny screwdriver often works, but sometimes the ring won't budge with a one point tool. Finally, don't even think about it unless you have a squeeze bulb blower to blow off any dust that might settle, or you could end up with more than you started with. I've removed internal dust from a 35mm Panoptic, edge-blackened the lenses of three Widescan II's, and several other eyepieces and binoculars. Most recently I disassembled an Astro-Physics 8x50 illuminated finder that had let dust in through an unplugged illuminator hole. Turned out perfect. I have never had a mishap and have always ended up with better than I started with, so I suppose it can be done, but I've been ready each time to pay for a repair or replacement if I did as you fear: ending up with a pile of glass and no idea which way or order to reassemble it. That is just a risk you take. It helps to remember it's only money. You'll eventually get more ;^).
Lee
If you have good dexterity and are good at cleaning fingerprints and smudges off lenses to your satisfaction, then taking eyepieces apart is not that daunting of a task. I did the same thing with a Speers-Waler Zoom--essentially completely disassembled it to get out all the dust.
Ease of disassembly depends on the eyepiece design--spacers and retaining rings, etc. Some lens configurations simply drop out in a single stack once a lower retaining ring is removed (Widescan II, for example). Others have internal rings holding things in place. These are harder to disassemble and reassemble. Sometimes you can only get an eyepiece partially disassembled before it becomes too difficult, but partial disassembly is sometimes enough to get to the stubborn debris to blow it out with a bulb blower or remove it with alcohol and a Q-tip.
Something that might help with some eyepieces is some kind of tool that can pull a lens carefully up and out of the barrel without having to turn the eyepiece over and let the lenses drop out, like a small suction cup--I assume these are available (and probably from Edmund Scientific Optics Division). Or you can hold a lens in place with the tip of your finger, turn the barrel over and gently drop it out if you must, though you must clean it properly (Q-tip and 99% isopropyl alcohol is what I'd use).
Another useful tool is a spanner wrench to grip the two opposing notches in a retaining ring. A tiny screwdriver often works, but sometimes the ring won't budge with a one point tool. Finally, don't even think about it unless you have a squeeze bulb blower to blow off any dust that might settle, or you could end up with more than you started with. I've removed internal dust from a 35mm Panoptic, edge-blackened the lenses of three Widescan II's, and several other eyepieces and binoculars. Most recently I disassembled an Astro-Physics 8x50 illuminated finder that had let dust in through an unplugged illuminator hole. Turned out perfect. I have never had a mishap and have always ended up with better than I started with, so I suppose it can be done, but I've been ready each time to pay for a repair or replacement if I did as you fear: ending up with a pile of glass and no idea which way or order to reassemble it. That is just a risk you take. It helps to remember it's only money. You'll eventually get more ;^).
Lee
