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Bulova AK7 Mainspring Replacement


jmplogin

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Hi all, I’m into my very first tear down, the watch is a Bulova Tank watch with an AK7 movement and I need some help.. I found the mainspring was broken and took it out, I bought a new one from eBay and then purchased some vintage winders. Unfortunately I didn’t make note which direction it was winded in the barrel. Is there a standard direction or standard manufacturers direction? Any help would be greatly appreciated.

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As the mainspring barrel sits in the movement, notice which side the barrel cover is on. If it's on the top (not dial) side, then the spring is inserted/wound in a counter-clockwise direction (outward spiral to the left). If the barrel cover is on the dial side of the barrel, then the spring is wound in the opposite direction (outward spiral to the right). The barrel, no matter which side the spring is loaded from, rotates in a clockwise direction as viewed from the top (not dial) side. Does this make sense?

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