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    Re: Mirror adjustment tools
    From: Brad Morris
    Date: 2017 Oct 6, 13:02 -0400
    Hello Hein

    You have mentioned that this sextant is covered in rust and that there appear to be seized bolts.  

    Unless this particular sextant holds sentimental value, you may wish to consider abandoning the effort and simply obtain a more serviceable unit. A quick peek at eBay shows thousands of units available.   

    Pick out the same model you have now and use the current one for parts.  Not everything is worth saving.


    On Oct 6, 2017 12:50 PM, "Hien Thanh Nguyen" <NoReply_Nguyen@fer3.com> wrote:

    We have written to Robert White and Ken Gebhart to ask if they have a some spare tools for sale. So far we have not heard from them yet.

    I'll keep on trying to see if I can make one that works some how. Drilling will be my last option but I really hope not to go there anytime soon yet.


    On Wed, Oct 4, 2017 at 10:23 PM, Stan K <NoReply_StanK@fer3.com> wrote:

    Have you tried to get/buy a tool from Ken Gebhart (Celestaire) or Ridge White (Robert E. White Instruments)?  I suspect Ken might have some, as they are used on the Astra IIIB.  (If he has them, get two, to replace your friends.)  Ken and Ridge both monitor NavList.

    If neither can provide you with one, let me know.


    -----Original Message-----
    From: Hien Thanh Nguyen <NoReply_Nguyen@fer3.com>
    To: slk1000 <slk1000---.com>
    Sent: Wed, Oct 4, 2017 7:00 pm
    Subject: [NavList] Re: Mirror adjustment tools

    Hi all

    I have tried several ways to make the mirror adjustment tool and so far I am pretty much defeated. 

    Here is the images of all the tools that I have tried to make. None of them is working.

    On top of that the tool that my friend sent me is lost in the USPS mail. The envelop came with a big hole in it where the tool is probably felt out and lost forever.

    This is sad. I just don't know why Plath made such a difficult adjustment screw to work with????


    On Sep 30, 2017 12:20 AM, "Hien Thanh Nguyen" <NoReply_Nguyen@fer3.com> wrote:
    Hi Stan

    Thank you for the info. 

    Peter and Mark just gave me some good idea on how to build a tool. So I plan to follow their leads to build my own tool. For the moment a good friend is helping me out by sending me his tool (from the astra 3b). I am hoping that this will work. Part of the problem is that the Sextant that I have is really rusted. The whole Sextant is pretty much rusted seized. I tried to deep it in liquid wrench and wd40 for several days, I also exposed it to heat and cold, but it is still hard to get moving. A few days ago I pretty much broke all the mirror mounting screws when I tried to unscrew them and take the mirrors out for resilvering. So I am afraid that even with the right tool the adjustment screw may not move. If this happen then I might have to give up on the restoration process.


    On Sep 29, 2017 4:55 PM, "Stan K" <NoReply_StanK@fer3.com> wrote:

    I'm just getting back from being away from email for a while, so I am late in responding to your message.  I see you already found something to work with the W&P.

    The photo of the CPlath adjustment looks like a square male "peg" within a round "can".  If I am correct, this is a common adjustment, as is used on the Astra IIIB.  Ken Gebhart might have these tools, though they are not listed in his Celestaire catalog.  Another possibility is Ridge White from Robert E. White Instruments (robertwhite.com), which is pretty close to you.  If neither of these pan out, I might know another source.


    -----Original Message-----
    From: Hien Thanh Nguyen <NoReply_Nguyen@fer3.com>
    To: slk1000 <slk1000---.com>
    Sent: Tue, Sep 26, 2017 12:25 pm
    Subject: [NavList] Mirror adjustment tools

    Dear friends:

    I wonder if you could help me?

    I have two old Plath sextants and would like to be able to obtain the tools to adjust the mirrors on them:

    1. CPlath sextant: this seems to have a square head screw. Please see the pictures here https://drive.google.com/open?id=0B8AuUsHvUgZjS0M0VXBRNWdfTXM

    2. Weems Plath sextant: this seems to have a round head screw. Please see the pictures here https://drive.google.com/open?id=0B8AuUsHvUgZjaXI4VGk5OV9rdTA

    I have looked high and low but can't seem to be able to find the tools for them. I have also sent to Celestaire.com to see if they can help me but I still have not heard from them.

    Is there anyway that you can adjust these mirrors by using tools readily available from home depot, or can you buy them from some where?

    Thank you for your help,


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