Cannon Pinion And Keyless Works 7006 Seiko

[steve855]

Hello all,

I'm having a problem with a seiko 7006. I bought the watch cheap, it was running but had a broken stem, otherwise it's pretty nice so I'm trying to get it fixed. I was able to source a new stem from a member at SCWF. I removed the calendar mechanism to access the keyless works and remove the broken stem. When I installed the new stem and tried to turn it while pulled out to the time setting position, I realized why the original stem was broken. It would not turn at all, and I could tell if I turned any harder the new stem would snap too.

Working on the other side of the movement, I removed the balance, auto winding mechanism, mainspring, pallet bridge and pallet fork, and main bridge. Then I put the main bridge and going train together without the pallet fork. At this point, the stem will turn when in the setting position, but the entire going train and escape wheel turns with it. I don't think this is correct, but I don't know have enough experience yet to diagnose what's happening here. I don't completely understand the relationship between the keyless works, cannon pinion, and the rest of the train. I'm not sure how the hands are disconnected from the train while in the setting position. I think the cannon pinion must be a big part of this but I haven't quite gotten a handle on it. If someone here is willing to shed some light on this I'll be closer to getting things working again. Let me know what other details are needed, as I'm sure I've left out something.

Thanks!

Steve

[CKelly]

Hi,

   It sounds as if cannon pinion may be on too tight. There needs to be enough tension on the cannon pinion to allow it to move with the drive train but still be loose enough to move fairly freely when setting the watch. I would guess that either the cannon pinion is rusted on or has been over tightened to correct a problem where watch may have been stopping at midnight. If this is the case the cannon pinion will need to be removed and either replaced or broached out a bit. Now removing it may be a problem in itself as it may be on so tight that you could snap the center wheel. It sounds as if you have had the cannon pinion off so it shouldn't break anything the second time. As for the movement turning when you try to set watch when pallet fork s removed well that may not tell you much. The drive train should be very free and smooth and without the pallet fork to stop movement then it would just be a matter of least resistance as to which would move. I may not have explained things properly or even understood the question as it is late here now but I wanted to help if possible.

Charles K

[Lawson]

Hi Steve,

 

Firstly, you've done really well diagnosing and trouble-shooting.  It's good to see you haven't "forced" anything to work or free-up; but have instead removed parts and retested.

 

You didn't mention pulling the canon pinion, and this is the next step in your trouble-shooting, as it may need to be clean, or perhaps derusted, and then lubricated with 9501 (blue) grease.

 

Firstly, you have mentioned that with the Pallet Fork removed, you now have a free turning Crown, and the Gear Train is spinning freely.  I'm assuming here that you inspected all the jewels and pivots in the Gear Train ... that being said,  your trouble-shooting has ruled out a bound-up Gear Train as the culprit.  The reason for the Gear Train spinning is that the complete train will spin even with a properly functioning Cannon Pinion if the Pallet Fork is removed.  The Gear Train has virtually zero fiction, and resistance of the Canon will stop it from slipping without the Pallets in place.

 

So next carefully replace the Pallet Fork, and gently attempted to rotate the Crown in the hand setting position again.    If the Canon Pinion is too tight, due to lack of lubrication, you will again feel that the Crown will not turn, this will now pin point it as the Canon Pinion, and not the Gear Train as the issue.

 

I hope I've explained this clearly. If not, please ask more questions ... THERE ARE NO STUPID QUESTIONS; not asking questions is what's stupid :)

[steve855]

Thanks Charles and Lawson for the helpful explanations. I suspected the cannon pinion was playing a key role here but I wasn't quite sure what it was. As I now understand it, the CP acts as a friction clutch to disconnect the hands from the train and allow setting the time. I knew such a mechanism had to be in there somewhere, but I didn't understand how it works. I'm a fairly mechanically-minded person but I'm still trying to adapt to working on such a small scale. Some of this stuff is really hard to see, as I'm sure you know. Charles, you are correct, I have had the CP off once, but I didn't know what to do with it so I just put it back on! I don't know that much, but I know that lubrication in the wrong place can be worse than none at all, so I figured some research was called for before proceeding any further. I'm still new to this and I don't even have any proper lubricants yet. I want to see if I have what it takes before spending the money on watch-specific oils. The question remains open...

I won't be able to get on with this until later today due to other obligations, when I do I'll focus my efforts on the CP and report back here with what I find. Thanks again, it's good to have a resource like this forum so I don't have to go it alone. Otherwise, I guess I would just buy another 7006 and try to learn that way if possible. This way is better.

Steve

[rogart63]

Is the movement looking like this? http://people.timezone.com/msandler/Articles/Workbench/Seiko/Seiko7005.htmlNot so familiar with seiko movements . But as it says in the text 7002  7005 7006 7009 is the same specs . I am sure you could find a to be found on SCWF forum about Seiko and Citizen movement  . Here is a lot of Seiko movements manual and repair   http://www.thewatchsite.com/14-user-manual-technical-manual-casing-guide-downloads/15-seiko-calibers-technical-repair-manuals.html

[steve855]

Yes rogart63 it's almost the same as the 7005 (7006 has day function. ) I have seen that Web page and i have the tech document but neither have much detail on the cannon pinion or keyless works.

Thank you.

Steve

[steve855]

Hi folks, just a quick update. I pulled the cannon pinion and lubed it very lightly with some MoS2 type grease I have. It did seem to help with the issue I described in the OP. Unfortunately, when reassembling the movement I managed to snap off the upper pivot on the pallet fork staff. This was a major drain on my enthusiasm, as I don't have a spare. I have some 6106 parts movements but the pallet fork is different, so at that point I was truly stopped. I decided to go ahead and finish assembly of the calendar mechanism on the dial side, which went ok. When this was completed, the problem of the stiff cp returned! I'm not sure what's going on there, but I knew it was time to set it aside and revisit things later, after I've recharged my patience. Although quite new to this game, I've learned that a certain state of mind is required, and proceeding without it results in broken parts and broken hearts.

I need to watch more of Mark's excellent videos and work on my technique. I'm stillstruggling with assembling the pallet & pallet bridge, and also the balance. My method of installing the balance thus far has consisted of "wiggle, turn, and hope", and I know there's a better way, if I can just learn it.

As always, thanks for the help and encouragement.

Steve

Edited January 19, 2015 by steve855

[Geo]

Keep at Steve, it will all come good in the end. :-)

[rogart63]

 This sounds nasty and i am afraid of writing it :D Have  you checked all the screws ? Have done it more than once . To long screw in the wrong hole .

 

Am i blocked now ? 

[steve855]

Geo- thanks

rogart63- that's a good idea. I'll check that. Due to work and family obligations I won't get back to this project until the weekend though.