Removal of Taper Pins

Discussion in '400-Day & Atmos' started by KurtinSA, Sep 7, 2019.

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  1. KurtinSA

    KurtinSA Registered User
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    Nov 24, 2014
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    I've got this Kern and Sohne which has taper pins holding the front and back plate on. I've disassembled the clock and am now trying to get the plates apart. Normally I would remove the front plate and dial but because of the tight fit, I have to work from the back so I can get access to the front plate taper pins. As you can see, the dial has taken a beating during its life.

    I've laid the dial down on my 2x4s and trying to get the taper pins out. They are brass and they come to a point...they're not cut off like some pins. I tried use of my small pliers and have used a thin sheet of brass to protect the plate. I've also let some Kroil sit overnight. I even found a punch that might let me apply concentrated force to the tip of the brass pin. But nothing is working. Also, more of the front dial is beginning to flake off.

    Any other ideas as to what I can do?

    Kurt

    KSFront.jpg KSTaperPins.jpg
     
  2. etmb61

    etmb61 Registered User
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  3. KurtinSA

    KurtinSA Registered User
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    Eric -

    And that works for removing the pins? It says it is a "pin seating tool".

    Kurt
     
  4. Uhralt

    Uhralt Registered User
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    Sep 4, 2008
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    Yes. Just use the slotted side on the thicker end of the pin so the pin will be pushed through the slot.

    Uhralt
     
  5. KurtinSA

    KurtinSA Registered User
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    I have a pair of pliers that can anchor on the post while pushing on the end of the taper pin. Normally with a steel pin that has been squared off, the pliers have something to grab on. In this case with the pin coming to a point, there is very little to push on. If I push too much I'll either round the end of the post off, scratch the back plate, or bend the pin making my problems worse. I'm going to consider a little heat on the pin/post joint...maybe get things to expand/contract and move the Kroil more.

    Kurt
     
  6. KurtinSA

    KurtinSA Registered User
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    Update...the pins are out. Not sure what did it...maybe everything! I tried heating with my mini torch...I'm a little uncomfortable around flames. Anyway, I didn't see any immediate help. But I kept doing the Kroil...heating/cooling cycles helps draw in the fluid. I came back after getting my mind off of it, and positioned the jaws on my pliers to give a straighter push on the pin and they began to pop out. I might have marred the back plates a little...guess those things happen. As it turns out, the pins on the front plate weren't on nearly that tight...they came right out.

    I wanted to see what was the setup behind the dial. As I was taking things apart, I saw a large thin washer just sitting by itself. As I suspected, it was supposed to be on the arbor for the minute (or intermediate) wheel...the small taper pin was MIA.

    Kurt
     
  7. KurtinSA

    KurtinSA Registered User
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    Another questions about this clock...not sure if the pictures show it very well. But the surface has a color, a sort of coppery color. What is this and how is it "attached" to the brass? I typically hand polish the bases with something like simichrome. Is there any danger to doing this in terms of taking something off that shouldn't be?

    Kurt
     
  8. KurtinSA

    KurtinSA Registered User
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    I understand that there is a plating of copper, so I'll have to be mindful of that.

    Kurt
     
  9. MartinM

    MartinM Registered User

    Jun 24, 2011
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    For polishing the Copper... Try Nev-r-Dull wadding. It's pretty good at brightening up the metal without applying too much abrasion.
    You'll want to remove any lacquer first though. A series of lacquer thinner-soaked rags should get the clear coat removed.
    If the Nev-r-Dull doesn't get all tot tarnish off (Make sure you got all of the old lacquer removed in the dark areas), I'd try Tarn-X, being careful to get it all off, afterwards and before recoating with clear lacquer. I've been saying for some time that with the exception of Nikolas brand, pretty much all of the rattle-can lacquers are junk. I've recently tried the Watco clear lacquers at Walmart and they actually work pretty well. They don't come off polished brass at a gentle touch like most. And they're about half the cost of Nikolas.
     

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