removing epoxy from a scope tube???

I'll try a few of the strippers and the MEK. I am told the acetone would do but perhaps I wasn't patient enough. I was thinking of turning most of it off in the lathe...................

Cerakote makes an air dry paint that could be used, but I don't want to lose the "Zeiss" labels!
 
Butch sorry to get back to you so late, yea I just had a customers scope returned from Leopold, he had it to close to a heater in the camper and it built up enough pressure to leak the nitrogen out, it fogged up first time he went out. Doesn't take much heat to build up pressure enough for it to leak out.
 
koginam,
It has been explained to me that they are purged with nitrogen or it is blown through. I don't think that it stays in the scope. There are several hundred modified scopes out there that have no nitrogen. None of mine ever fogged.
Butch
 
Leupold nitrogen purge

Butch Lambert said:
koginam,
It has been explained to me that they are purged with nitrogen or it is blown through. I don't think that it stays in the scope. There are several hundred modified scopes out there that have no nitrogen. None of mine ever fogged.
Butch
Click to expand...

Butch,
This caught my interest so I called Leupold Technical Support. The scopes are inerted and slightly pressurized with nitrogen so heating the tube could damage the integrity of the O-ring seals.
Chino69
 
FYI, nitrogen is a dryer. It removes damp air and replaces with dry nitrogen. It does not need to last after evacuation of the vessel that has been purged of moist air.

Remember that the external pressure would have to exceed 14.2 lbs gage, before any other gas could replace the nitrogen.

So what does the scope contain after it has been purged? It's easier to say it contains no moisture.
 
Nitrogen

Big Al said:
FYI, nitrogen is a dryer. It removes damp air and replaces with dry nitrogen. It does not need to last after evacuation of the vessel that has been purged of moist air.

Remember that the external pressure would have to exceed 14.2 lbs gage, before any other gas could replace the nitrogen.

So what does the scope contain after it has been purged? It's easier to say it contains no moisture.
Click to expand...

Yes,
Nitrogen is used as a moisture replacer. Once the interior is inerted with nitrogen, it will remain that way until the seals are damaged and moisture is allowed to creep back in.
Chino69
 
I'm not sure what pressure if any is in the scope, it just has a nitrogen environment inside the scope, but if it is heated what ever is in there will expand and can blow the seal, allowing moisture in. Most top quality scopes that I have played with use O-rings for sealing as well as grease on the threads. cheaper scopes use just grease.
 
"Remember that the external pressure would have to exceed 14.2 lbs gage, before any other gas could replace the nitrogen."

Not exactly.
The partial pressure of nitrogen at sea level is only around 11 PSI.
While a gauge shows the pressure of ALL the gases in a container, the individual gases also have their own pressure fractions and leak/diffuse in (& out) based on the partial pressures.
Oxygen is trying to get INTO the scope at about 3.7 PSI (if it has 100% notrogen fill) no matter what other gasses are present and the pressure they have.

Scopes are NOT hermeticaly sealed since they use rubber to allow for focusing and movement.
 
brickeyee said:
"Remember that the external pressure would have to exceed 14.2 lbs gage, before any other gas could replace the nitrogen."

Not exactly.
The partial pressure of nitrogen at sea level is only around 11 PSI.
While a gauge shows the pressure of ALL the gases in a container, the individual gases also have their own pressure fractions and leak/diffuse in (& out) based on the partial pressures.
Oxygen is trying to get INTO the scope at about 3.7 PSI (if it has 100% notrogen fill) no matter what other gasses are present and the pressure they have.

Scopes are NOT hermeticaly sealed since they use rubber to allow for focusing and movement.
Click to expand...

The 14.2 lbs is absolute pressure of air at sea level. So the reading is 14.2 lbs gage absolute. And no air @ 21% O2 and the balance of nitrogen is going to leak into the scope. It is not in a vacuum, it is not under any more pressure than atmospheric pressure. By that, I mean pressure ambient to the scope body.
 
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