Need a little help wrt AS 1803 Movement

[nlapietr]

Hello,

Need a little help please.  I have been playing with an old Elgin SH1803 movement (probably mid 60's).  I have acutally been successful in tearing it down and rebuilding it several times (well mostly successful).  It seems I have it back together correctly (the gear train spins, it has a heartbeat even if it is anemic, the second hand sweeps, and I can set the day, date and hour) but the hour and minute hand do not move when it is in "run" mode (i.e. stem pushed in).  It seems that those hands are not receiving power...  I have to admit, I am baffled.  Any ideas?  I

Thanks in advance.

[HSL]

Most times you can set the hands with the crown but they don'y move in normal mode you need to tighten the cannon pinion.
There is a special section for help and advice here too 
https://www.watchrepairtalk.com/forum/4-watch-repairs-help-advice/

[nlapietr]

All,  I am about at my wit's end.  The cannon pinion theory does not seem to make sense to me.  It slides over a tube that is inserted from the other side of the movement.  The seconds hand (second wheel?) pinion comes through the tube but I can't see how the cannon pinion is driven as the tube is not rotating, at least not that I can see....  the minute wheel is driven by two intermediary wheels, one that seems to run off the barrel, and a second which to run the minute wheel and cannon pin.  I am wondering if that second intermediate wheel is somehow disengaging....  Any thoughts?

[nlapietr]

My apologies for doing this again in the wrong forum.

[Shane]

Hello nlapietr,

I found your question while Googling something unrelated but I share in your frustrations.

I am in need of the wheel that is driven from the barrel and in turn drives the pinion circled (as well as the rest of the watch).  On my 1803, this wheels pinion, has lost the fit with it's wheel and nothing at all is being driven.  The barrel wnwinds as fast as its being wound and nothing else happens.

Your trouble should center on this spot.  This gear provides the clutch function of the traditional cannon pinion and is how power is translated from the train wheels into the hand wheels.

I hope this helps you.

Shane

[Nucejoe]

Its called offset canon pinion, should be tightened enough to

 

1 hour ago, Shane said:

 This gear provides the clutch function of the traditional cannon pinion and is how power is translated from the train wheels into the hand wheels.

I hope this helps you.

Shane

Do not overtighten, grease it, do not oil.

There are canon pinion tightening tools, I have dulled the cutting edge of a nail clipper and use it as the tool.

 

[Shane]

23 hours ago, Nucejoe said:

Its called offset canon pinion, should be tightened enough to

Nucejoe,

Thanks for the nomenclatural support.

Didn't know about the lubrication requirement for this design.

I'm under the opinion that the aforementioned oiling isn't my problem.  It seems the wheel on this axial assemblie was staked onto the shaft, (in about eight to twelve spots) and now it is slipping.  I'm not sure if it was from the factory or someone's attempted repair but it looks very regularl in spacing and depth.  I've tried shellacking it but it soon sheers free.  There isn't enough room for a good reinforcing fillet and it's to thick to wick in, if any clearance did exist.  I think I will try something a bit more modern as adhesives go.

Does anyone have a suggestion?

Edited July 4, 2021 by Shane

[Nucejoe]

1 hour ago, Shane said:

'm under the opinion that the aforementioned oiling isn't my problem.  It seems the wheel on this axial assemblie was staked onto the shaft, (in about eight to twelve spots) and now it is slipping.  

I think I misunderstood you, heres a picture of an offset canon pinion,

 

so, the gear is loose in your watch. In that case some folks peen the drive gear hole and adding shelac can't hurt.

 

 

[menez718]

On 7/3/2021 at 9:22 AM, Nucejoe said:

, I have dulled the cutting edge of a nail clipper and use it as the tool

Thanks for the tip!  I tried to use my staking tool but the offset cannon pinion is too small to fit on the stump.  Old nail clippers did the trick and now my watch keeps perfect time.

[WpgRob]

The slipping second wheel (I’ll go rogue and call it wheel 2) strikes again. Exactly the same issue happened to me today. It seems the rivet fixing the staff to the wheel can loosen when the offset cannon pinion is pulled off from the dial side. Since the fixed pinion of wheel 2 is the only pinion that engages with the mainspring barrel, any slippage can let down the mainspring by spinning the staff in the rivet to the wheel on one end, and spinning in the cannon pinion in the other end. The rivet is too weakly attached to its wheel to resist the mainspring torque. Perhaps a better way to release the cannon pinion would have been to separate the cannon pinion from the fixed pinion by twisting a screwdriver between them.

 

[Neverenoughwatches]

4 hours ago, WpgRob said:

The slipping second wheel (I’ll go rogue and call it wheel 2) strikes again. Exactly the same issue happened to me today. It seems the rivet fixing the staff to the wheel can loosen when the offset cannon pinion is pulled off from the dial side. Since the fixed pinion of wheel 2 is the only pinion that engages with the mainspring barrel, any slippage can let down the mainspring by spinning the staff in the rivet to the wheel on one end, and spinning in the cannon pinion in the other end. The rivet is too weakly attached to its wheel to resist the mainspring torque. Perhaps a better way to release the cannon pinion would have been to separate the cannon pinion from the fixed pinion by twisting a screwdriver between them.

 

There is a dedicated tool for this...an offset cannon pinion remover. This has two thin platfoms  that slip between the  two pinions and seperate with an reverse plier action .