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Taking apart a Siebert 40mm 70degree OB

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#1 Tank



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Posted 05 December 2012 - 02:20 PM

Anyone take apart a Siebert EP to clean
Has a bit of dust so thinking of try to get at the elements.

-The top lens is pretty easy to get at no problem cleaning it.
-The bottom lens is deeply recessed into the 2" barrel

There seem to be three top LN key screws at the top whcih takes the top housing off with the top elements in it.

There is then 4 LN key screws at the bottom which seem to hold the bottom barrel together. However taking these off the bottom barrel is still stuck to the main housing??

Anyone go thru a disassmbly of a Siebert? :confused:

**Not too bad as far as dust is concerned right now but would be good to know for future cleaning

#2 BillP


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Posted 05 December 2012 - 05:29 PM

He uses some unconventional methods. In one of my Sieberts the lens was sitting between 2 rubber o-rings. When I took those out to my surprise the lens did not budge. I had to heat the housing so it would expand and then the lens had clearance to come out. On others, he had lenses mounted in a cell and set screws on the outside of the barrel held the cell in there. Sorry...never tried to take an OB apart.

#3 avenger


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Posted 06 December 2012 - 12:06 AM

Send it to Harry, he will clean it for next to nothing. I sent him my 40mm OB and he charged me nothing.

#4 Tank



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Posted 06 December 2012 - 09:39 AM

Thanks guys
I cleaned the eyepiece pretty good.
The dust on the bottom lens was mainly loose so using a blow bulb and a vac clean it nicely.

I email Harry and he said he could clean it for me, good option to have in the future.

When i took mine partially apart it looked like there was a few O-rings holding the elements, didnt want to tamper with them.

Cant wait to get to use it a bit more.
First light was yesterday at F5 and it did good. Edge correction was ok. The eyeplacement was great easy to pan around. Bought it mainly for my F7.5 / F15 want to see what it can do.

#5 ensign


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Posted 06 December 2012 - 12:05 PM

I'm glad first light with the 40 was a good experience, Tony.

Clear skies to you.

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