GMT 1675 & 16750 hand set identification & 16700, 16760 & 16710 hand differences

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springer
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GMT 1675 & 16750 hand set identification & 16700, 16760 & 16710 hand differences

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TO.....BE....CONTINUED - TO INCLUDE THE FINAL EDIT AND SEVERAL PHOTOS DEPICTING THE 1675 AND 16750 HAND SETS


BASIC GMT-MASTER 1675 AND 16750 HAND SET IDENTIFICATION

I often get asked about the correct hand set for a GMT 1675 with the 3075 movement. The 1675 hand set is interchangeable with the earlier 6542 but there are visual differences between the earlier and later 1675 hands. In this post, I will focus on the hand sets for the 1675s from around 1966 until the end of production as well as the GMT 16750, 16760 and 16710 hand sets. The information in this thread was not intended to be an all inclusive history of the various GMT hands, but instead, it is meant to help collectors that have some basic knowledge of the various GMTs and provide assistance in identifying correct GMT hands for a particular model.

First off, the GMT-MASTER 16750 hand set and the 1675 hand set are not interchangeable. The hand stack for the GMT 1675 has the 24-hour hand on the bottom, then the hour hand, then the minute hand and finishing with the seconds hand on top. As you'll observe in the photos below, the 24-hour hand has the largest center hole, then the hour hand center hole gets smaller and so on for the last two hands.

On the GMT 16750, the hour hand has the largest center hole and is on the bottom, next is the 24-hour hand which has a smaller hole then the minute hand and finally the seconds hand. The center hole on each hand is different in size for the 16750 hands when compared to the 1675 model. Collectors often confuse the differences between the hand sets for the 1675 and 16750. Of a particular note is the minute hand for both models. While the minute hands might appear similar, the center hole for each hand are not the same size. The GMT 16750 minute hand has a larger center hole and it is not interchangeable with the GMT 1675 minute hand which has a smaller center hole when compared to the 16750 minute hand. Additionally, the mounting post for the16750 seconds hand is very short and not near as long as the 1675 seconds hand mounting post. Like the minute hand, as well as the other hands, the seconds hands are not interchangeable between the GMT 1675 and 16750 models.

There are also two variations of the 24-hour hand found on the GMT 1675. The first generation 24-hour hand had a small, equilateral, triangle shaped red pointer while the later, next generation pointer had a much larger red triangle tip. The smaller version can be found through 1966 models and occasionally may be found on 1967 GMTs and possibly on some early 1968 GMTs.

DIFFERENCES BETWEEN THE GMT 16750, 16700 AND THE GMT II 16760 (Fat Lady) AND GMT II 16710

These hand sets are often confused with each other and although they are basically the same, there are two variations of the seconds hand. I have seen 16750 hand sets advertised for sale that will fit all four of the later GMT/GMT II models which is not correct. The GMT 16750, GMT 16700 and GMT II 16710 complete 4-hand sets are all interchangeable with each other. The GMT II 16760 Fat Lady hands are interchangeable with the other three later GMT models except for the seconds hand which has a longer mounting post than the 16750/16700 and 16710. I would call this seconds hand mounting post on the 16760 a medium size post, the 16750/16700 161710 has the short post and the GMT 1675 has the long mounting post.

GMT AND GMT II MOVEMENTS:


GMT 1675: 1565 non quick-set (marked 1560 on the bridge, replaced by caliber 1575 around 1965)
GMT 1675: 1575 non quick-set (marked 1570 on the bridge - hacking feature added during early 1970s)
GMT 16750: 3075 (with quick-set date setting function)
GMT 16700: 3175 (replaced the GMT 16750 with quick-set date setting function)
GMT II 16760: 3085 (semi quick-set date setting function with independent hour hand)
GMT II 16710: 3185 (semi quick-set date setting function with independent hour hand)
GMT II 16710: 3186 (semi quick-set date setting function with independent hour hand. Found in the GMT II during
the last year or two of production. )

IDENTIFICATION OF AFTERMARKET GMT-MASTER HAND SETS
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