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BFG 158 31/7 Spring help


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I have learned 3 things with the disassembly of my first watch.

1. Watch face retaining screws are impossibly small. On the BFG you have to remove one of them completely to get the face off.  Then, when you tweeze them back into place with a crappy tweezer, the screw torques out and is gone forever.  Use better tweezers and don’t squeeze so hard. 

2. When you practice reassembling parts to help memorize it for final assembly, don’t use the work surface to flip over and re-orient springs with your tweezers. As soon as you let go, the spring finds a new home in witness protection somewhere in your workroom, also, never to be seen again.  Perhaps it is neighbors with the dial screw?

3.  This stuff is fun. 

I can't seem to find a source for this spring, and I am not dropping 100+ USD for a parts movement. Therefore, I may have to make it.  Anyone have experience with making springs?  

Where do I source the spring steel?  I saw someone use piano sting wire to create one.  

Any help or advice here would be appreciated.  

 

I have circled the part in the pic below.

 

-Devon

image.thumb.png.e48e2d8c3c5c574bf6df8e2fe12897d2.png

 

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Tip: don't loose parts. Good practiced technique helps but it's a known hazard. Arrange your workspace so that springs and screws that do go missing are easy to locate. Put a back face on your desk, and ridges on the other edges. Keep your floor space clean and uncluttered. You can use magnet to comb the floor (some people make magnet brooms for this) and you should be able to find your parts. Trust that they are there, it just takes patience. I work over a carpet (! ?) and with my magnet-on-a-stick I still manage to find 95% of missing parts. There's tricks to springs and screws: using pegwood to de-tension or hold the spring; using rodico to hold parts as you remove them; holding a thin clear plastic bag over the movement while you remove the part to catch it if it does try to leave.

 

There's lots of parts that are hard or impossible to replace. Fortunately, those "shepards hook" springs are not particularly special, you can buy them in bulk for a few dollars from your parts supplier and use the one in the pack that fits best.

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As @KOwatch says, when first working with very small parts (especially spring), use some Rodico to move them, or restrain them while you use tweezers. 

Also, work on a surface which is slightly flexible (I use a bit of vinyl flooring) - less likely to launch small parts across the room.

And buy a strong magnet. I think I've found all parts, eventually. If the magnet doesn't work, I clean the dust chamber of the Dyson, and sweep the whole room. Enter the contents on to some clean white paper.

Keep practicing, it does get easier !
(though I still get the odd spring that makes a leap for freedom)

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