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HAC (Hamburg American Clock) problem


clockboy

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I was asked to look at this non running "Hamburg American Clock". It is a half hour/hour striker and it has not run or chimed for over 20 years. The problem I have no idea how the strike is supposed to work & can not get it to work.

 I have attached a vid at the end of the vid when i say pin I mean the stop pin on a wheel. Maybe something is missing.
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The gathering pallet is in the wrong place. It should be free from the rack when the striking has stopped, it look as if it is still in the racks teeth. These striking movements work the same way as a French strike. Try that first. I’ll have another look and see what else I can find by watching.

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I tried that but still no luck. I have attached  couple of pics. The wheel with the red arrow has a real wobble but I can not see how this effects the strike. The purple wheel is the pin that stops the hour strike. IMG_3652.thumb.jpg.9924eb63ca4b64557d4b8932e2645580.jpgIMG_3653.thumb.jpg.c904596c3f9ab17376d4d5b466299372.jpg

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I would check behind the snail for wear and the part with red arrow and make sure all is correct. These clocks are prone to wear in the strike as the brass is of poor quality. It might be a good idea to take off all the strike make sure the wheels are in there proper place and re-build inspecting every part as you go. Are you sure, the wheel with the wobble does not have a bent pivot. Don’t forget the two pins on the minute wheel, if they are worn or bent the lever will not rise as it should.  You have a wheel missing that is why the snail is so loose. Have you removed it?

IMG_3653.jpg.2e6a3baeb41565e862e8de46d55d7f4f.jpg

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Yes the wheel missing has been removed whilst I was fiddling. On the half hour the lever does not rise enough and I suspect the lever is worn but I might be able to adjust. The wheel with the wobble has not got a bent pivot the whole wheel has been bent. I will try to straighten. I will check everything yet again but I still don't understand how it works. 

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Looking at the photo with the purple arrow, the leaver that the arrows is pointing at looks to me to be on the wrong side of the calm shaft, put it on the underside and I think that will fix the issue. Note how the the flange off the lever is sitting up in the air that should be sitting in the lifting star, also the spring will need to be adjusted to be hitting the pin on the same lever. It looks like as you say some 20 years ago someone took the movement apart and put it together the wrong way.

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I have a French movement in my stock of spares and a quick look it seems it works using the same method so I can compare the two.  However I have family commitments today so this project is on hold at present. 

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Problem fixed it was the leaver I have marked with the blue circle had slipped on to shaft, this in turn put the lever with the purple arrow too low and was fouling the hour stop pin. I have adjusted and added a touch of loctite to make sure it now works a treat.

 

IMG_3652.thumb.jpg.22388f4d15144e5b281521432ebbc839.jpg

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