Seiko 6117A - excessive barrel wear on main plate

[SpringMangler]

Working on a Seiko 6117A which has terrible amplitude and the timing is all over the place, occasionally stopping.

The mainspring barrel has a lot of play when in place, but no side play on the bridge bushing. As you can see from the attached picture, the mainplate has significant scoring on one side and the hole for the barrel has worn on the same side as the scoring. 

This particular movement is like hen's teeth, and very hard to get parts for so would appreciate any advice on options. I've seen jeweling kits for similar movements (think the base movement is the 6106) but they are not cheap.

Oh, and a previous person who serviced it scratched deep numbers onto the main bridge and main plate to match the service number on the case back. 

Edited May 17, 2023 by SpringMangler

[Waggy]

Hi there, not sure if this will be of help to you, but the link below has helped me resolve a lot of issues.

Hope it helps

[SpringMangler]

16 minutes ago, Waggy said:

Hi there, not sure if this will be of help to you, but the link below has helped me resolve a lot of issues.

Hope it helps

Thanks for that. I was thinking of this, but the worrying part is the groove on the left hand side of the locating hole which is lower than the other side.

 

[Waggy]

Do you think someone has already had a go at fixing it and the groove is the result?

[SpringMangler]

36 minutes ago, Waggy said:

Do you think someone has already had a go at fixing it and the groove is the result?

I did wonder if someone had got a bit excited with a staking set. The groove on the hole is quite uniform in shape.

There is also quite a bit of play between the barrel and arbor. After cleaning and installing the arbor without the mainspring I am able to tilt the barrel quite a bit whilst holding the arbor between tweezers. 

Here are some of the marks left on various bits of the movement....

Edited May 17, 2023 by SpringMangler

[Waggy]

A little out of my league, perhaps someone tries a clock fix on a watch? Maybe someone else will have a good fix for this if you give it a few days to give people a chance to see this post. If not you have nothing to loose by trying to close the hole with a staking set as I don't think you can't leave it the way it is. Death or glory!

Hold on..... I just had a thought, maybe you could open up the hole with a reaming set and put a jewel in there, I think I saw a YouTube on this... Will try to see if I can find it.

Here is a link to a similar video as I can't find the exact one I was looking for, but I think it covers the same stuff, I think VTA on eBay supplies the kit.

 

[SpringMangler]

I've had a look at that option and it does give a warning about the 6117 movement, which is just my luck:

"Please take great care when installing these on the 6105 and 6117 movements. Due to the step on the calendar side of the plate, the reamer gets pushed to the side and it is very difficult to ream the hole correctly. If done incorrectly, the plate will be ruined."

 

[Waggy]

That's a pity, it Looks like you may have to hunt for a donor or spare part unless anyone out there has a solution we haven't thought of.