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Antique Clocks/clock winder size


I have recently come into possession of a Haid mantle clock that my finance bought for his mother years ago.  Somehow the winding key has been misplaced.  Can you tell me the size of the key so I can purchase a new one.  Thank you so much for your help.

The chart I have for key sizes is found in Merritts online catalog. ( To determine the correct key size, first use a micrometer to determine the flat to flat size of the winding arbor. A micrometer which will measure this is available at Harbor Freight for $9.99 during their sidewalk sale this weekend (Friday-Sunday). You probably need either a size 4 or 5 key. The size 4 is for 3.2mm and the size 5 is for 3.4mm. It is easy to calculate larger and smaller arbors as ever two tenth of a millimeter higher increases the key size one point. Smaller ones decrease it one point per .2 of a mm. It is always better to get one a bit larger than smaller. Merritts sells these keys for as little as $2.75 each. They appear on page  76 and 77 in my catalog. On an order of this small magnitude there would probably a $3 or $4. handling charge, however.

While you;re at it you might order some clock oils so you can lubricate your clock as necessary.  

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Tom Williams


I can not think of any questions I cannot answer in regard to repairing antique clocks or radios. However, I am sure there are a few I have not heard and may not be able to answer. If I cannot, I will say so. I have been repairing them since I was a young child.


My experience includes repairing CooKoo clocks, Westminsters, BimBam, almost all antique clocks. I do a bit of repair on battery clocks where the value is sufficient to warrant working on them. I also repair antique (tube type) radios - all makes.

Indiana Historical Radio Society, Illinois Valley Antique Car Club, Military Vehicle Preservation Association

BEE from Cleveland State University

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