Gustav Becker Wooden Case 400-Day

Discussion in '400-Day & Atmos' started by MuensterMann, Jul 12, 2019.

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  1. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    I have a Gustav Becker 400-day clock that instead of a glass dome, it comes in a mahogany case. I notice in an old Tran Duy Ly price book that these tend to be higher - perhaps not many were made in the wooden case display. It has a disk as the pendulum.

    The movement back is shown below and has a number of 1991164, and matches the number on the pendulum. I believe the clock is from around 1905. I am not sure of the exact plate number, since more than one seem to fit.

    I cleaned the movement and it is freshly lubricated. I used a .004 inch suspension spring and I am trying to size the length properly to get the timing right. I am an inch or so above the floor of the case (it looks high) and I still must shorten it as it is moving too slow (outside the range of adjustment of the pendulum). I can only get the pendulum to swing 180 degrees, although it is enough to work. Does all this sound normal for this clock?

    Thanks!
    back plate.jpg
     
  2. KurtinSA

    KurtinSA Registered User
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    Nov 24, 2014
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    The clock dates to the later part of 1907. Can you show a picture of the case and/or clock in the case?

    Shortening the spring to make it run faster has an effect, but the best way is to use the proper thickness spring. If it's running slow, then the standard spring needed to be thicker than 0.004". I believe the only spring available about that is 0.0045" which might be too fast...but you didn't say what kind of timing you were dealing with. You might have to thin the 0.0045 spring down appropriately. Keeping the spring at a length where the pendulum is about 1/4 to 3/8" above the bottom would certainly look better.

    It's not so important what the total rotation is. What is the amount of over swing? That's what defines if the clock will run or not. To get more total swing, likely positioning of the fork will help that...at the expense of over swing. So you could raise the fork to get more total swing, but if your over swing gets too small, then the clock won't run.

    Kurt
     
  3. John Hubby

    John Hubby Principal Administrator
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    #3 John Hubby, Jul 12, 2019
    Last edited: Jul 22, 2019
    MuensterMann, you probably have a GB Model No. 480 4-Glass Mahogany (or Oak) lift-off Top wood case. These were made from 1903 to 1912 in quite a significant number, one of the nicer designs produced by GB. Kurt's dating is correct for your clock.

    GB disc pendulum clocks generally have the problem that a 0.0040 spring isn't strong enough to allow bringing the clock to time (runs too slow at max fast adjustment). Unfortunately the next spring available is the 0.0045, usually much too strong. My experience is you will need to thin the 0.0045 to between 0.0041 and 0.0042 to bring the clock to time. This is tedious and "must" be done by removing both the fork and top block to do the thinning; stroke from the bottom block for the full length of the spring. You can check your results by only replacing the top block and hanging from the upper bracket, turn about 3/4 turn and then time how long it takes to make 8 beats with the pendulum weight adjustment at center position. Should be slightly less than 60 seconds for best results.
     
  4. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    Thanks Kurt and John for the information! Okay, late 1907. The wood is mahogany. Since many were made, is the price higher because folks like the wooden case? Seems only GB made them and I guess only during that period. If popular, someone else would have made them as well. Perhaps more popular now! Here are some photos below (in the non-clean state). I will work on getting that .0045 inch spring thinned! My only other problem is either the hands are snagging or something near the dial is snagging. Tending to that issue as well.
    left.jpg right.jpg str.jpg
     
  5. KurtinSA

    KurtinSA Registered User
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    Nov 24, 2014
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    Sweeet!

    Kurt
     
  6. daveR

    daveR Registered User
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    Sep 10, 2008
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    Very nice clock. espcially the bevelled glass to thecase.
    If the hands are catching, butnot on each other as they pass (which is obvious anyway) you may have to look under the dial and see if the minute wheel is not catching on the hour wheel of the cannon. Itshould be well away from it but if a pin comes out it might slide forward, also hopefully ,especially on a becker of this age it shoildnot happen there is clearance all around the dial hole where the hand arbors pass through.
    David
     
  7. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    The hand arms are not touching, but perhaps a slight burr on the hour hand or back of minute hand. The dial is off at this point. So, perhaps something behind the dial. What pin are you referring to as maybe coming out? The one that hold the minute hand on?
     
  8. daveR

    daveR Registered User
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    what is referred to as the minute wheel, which is the wheel with attached pinion and provides the reduction from the centre arbor minutes drive to the hour wheel. (The hour wheel overhangs it) , but if it is not held securely back on its pin by a locking pin and sometimes a washer, it can move backwards and forwards where the overlapping wheels can catch each other. Sorry this is a bit long winded, but short of worn teeth or a bent arbor, very unlikely on this clock, I cant think of anything outside the plates cause the snagging you refer to.
    David
     
  9. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    Just to clarify, the burr I speak about may be on the hub of the hands. The clock will stop and I can feel a slight resistance on the minute hand and with a little pressure it can be overcome.

    Added the .0045 inch after a little thinning. The disk is about 3/8 inches off of base. I am now at 8 ticks per 56 seconds, and must thin to get to 60. With the .0040 inch suspension spring I was at 1:03 seconds. Now, the disk rotates about 2/3 of the 180 degrees - but still has over-swing to work. I wish for more swing! In terms of moving the fork up or down, there is not much range to work with.
     
  10. daveR

    daveR Registered User
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    Sep 10, 2008
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    Ahh, OK . I might have been looking up the wrong tree ! It sounds like you have in idea of what the problem is.
    David
     
  11. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    After 20 strokes with emery cloth between my fingers, not much difference. Then I found some sticks with some sand type of paper on them and after 15 or so firm strokes, I was at 58. Another 15 got me to 60. So, I am getting there!
     
  12. MuensterMann

    MuensterMann Registered User

    Mar 23, 2008
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    Resolved the hands getting hung up as something near the hub was not quite smooth. Keeps good time. The rotation is only 180 degrees total, but it works.
     

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