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hermle 340-020 movement not running


arron

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Hello,

I am working on a 1977 hermle 340-020 movement that has been wound tight and hasn't run since at least 1994.  it has a floating balance.  before deciding how or whether to repair it I would like to try and diagnose the problem(s).  
    
    The movement looks to be in excellent condition although I can see a bit of crud in some of the pivots.  Although fully wound, when I push the balance wheel it moves for just a few seconds and stops.  I then took the balance wheel out and moved the pallet fork back and forth and the escapement wheel does move; but if I just touch the pallet fork on one side it doesn't pivot on its own to the other side (as though it's not getting enough power from the mainspring).  
    
    Also, when I put the minute hand on and turn it manually I'm not getting any movement from any of the wheels as I would expect if it were trying to strike or chime.
    
    Are there any tests that I can do to pinpoint where the issue(s) might be without further disassembly?  Much thanks for any insights.  Be well.  Arron.
    
Ps while writing this, the chime side started spinning but only when laying down, not upright.  And a bit later, when I turned the movement over on the other side, the strike side started spinning.  not sure what all this means.  maybe it just needs a deep cleaning and new springs?

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The Hermle movements are quality, from your description of the problem it is in need of a good service this includes removing the mainsprings from the barrels and cleaning them and barrels also  The floating balances are self contained units an must be treated with care.  Remember to remove the power from both springs before doing anything.  There is a Hermle clock manual, I got mine from Cousins its a mine of information.

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Looks as if its as dry as a bone. A clean and oil I think all is needed. To be fair you never know until you take it all to pieces and checking the wheels such as pivots,teeth,pinons and the pivot holes. These movements are made of a soft type of brass and steel.Always use a good mainspring winder to remove and re-install the springs. When it comes to the floating balance both ends should be jeweled, a tiny drop of oil on both ends then work the balance up and down a few times to make sure the wire is oiled and that should keep the balance nice and free and floating. Oil the pallet pins but not to much and every other tooth of the escape wheel. The rest of the movement should be oiled in the normal way.   

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  • 3 months later...

After your good advice i cleaned the movement and put it back together.  The springs all looked fine to me.  the time train seems to be working well, but the chime and strike side are acting weird.  when i turn the minute hand there is no striking or chiming until i get to the top of the hour, then it chimes.  at that point the gathering pallet turns at most one time (or a partial revolution), pauses and then turns one more time.  no matter how many times i turn the minute hand, the gathering pallet never climbs the entire way up the rack.

i don't put it passed myself and my skills that i put something back the wrong way (i did that on the chime side and luckily figured out my error).

another observation i just made is that in the middle of the chime, the bar that raises the striking hammers lifts and holds those hammers up while it's still trying to chime.  and at the end of the chime, the striking hammers bar lifts again holding those hammers up instead of leaving them down in the resting position-it doesn't do that every time though.  sometimes a chime only hammer will be left in the up position.

 

it's a mystery to me what's going on.  Any advice appreciated.  thanks.

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You haven’t got the strike and chime set up right. On the centre wheel you have the cannon pinion with four points on it, the shortest is for the quarter past then half hour, a quarter too ant the longest is the hour. The cam wheel has four grooves in it the shortest space between the grooves is for the quarter past and so on until the longest gap is for the hour, you need to have both in line. The strike side the wheel with the pin in it next to the fly wheel should be set about 10 to the hour. Make sure the wheel that lifts the hammers is completely free from lifting the hammers, all hammers must not be in the way of the wheel when it comes into the warning that is when the hour hand is about 10 or 5 to the hour. The gathering pallet must also be away from any of the teeth on the rack until it starts striking. Let me know how you get on with that it probably will need fine adjustment.

I have found this it will help you.

 

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  • 4 weeks later...

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