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Smiths 27.CS Info & Advice


jaycey

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Evening chaps,

 

3/4's of the way through servicing a Smiths 27.CS with date & hacking and I have realised I didn't pay attention to the hacking mechanism during assemble and now I have no idea how it operates??

I can't see what interacts with the hacking assembly to move it forwards and backwards to engage with the balance wheel (which it is doing perfectly)

 

Also, does the return bar spring push against the tab for the hacking lever or hook behind it? Picture below.

 

IMG_0701.jpg

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Oh! Now I see. You were just resting the return bar spring on the setting lever while trying to figure out how it interacts with the hacking lever. At first glance I thought you placed it on the setting lever pin rather than below the return bar. I now understand the problem. I guess my pictures won't help at all because they don't show the interaction of the return bar spring and the hacking lever. 

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Thanks for taking the time to reply John.

Indeed, just resting the spring there before assembly.
Yes, just need to know the orientation of the spring with the hacking tab & what is actuating the hacking lever under the mainplate as it is moving correctly even without the return bar spring in-place.

Thanks


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  • 2 weeks later...
On 11/15/2018 at 8:04 PM, jaycey said:

Thanks for taking the time to reply John.

Indeed, just resting the spring there before assembly.
Yes, just need to know the orientation of the spring with the hacking tab & what is actuating the hacking lever under the mainplate as it is moving correctly even without the return bar spring in-place.

Thanks


Sent from my iPhone using Tapatalk

The tail of the hacking lever needs to be compressed against the main plate, just as you show in your photo. It is easy for the spring to ride up over the hacking lever, so you must carefully insert it. You may find that it still rides up, but the cover plate will help to push it downward. There is a semicircular rebate where the spring sits which is stll accessible with a screwdriver once the cover plate is going down, in case you need to adjust the spring position. You may need to adjust the hack lever position by bending once assembled.

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