Tightening a "THINGAMAJIG"

[richard]

Hi,

I'm tinkering with a movement from a Greville watch and the clutch/cannon pinion equivalent is very loose and hence the hands don't move, although the watch works OK. It's the type with a gear fixed to the mainspring barrel, not sure what it is called, but does anybody know if it's possible to tighten them up. 

[rogart63]

You will have to show us some pictures or link to a similar watch. So we now which movement we are talking about. 

[richard]

Thanks, photo added

[jdm]

3 hours ago, richard said:

Thanks, photo added

What was asked is a picture of the mov.t, not of the part itself, which doesn't tell much.

[rogart63]

Think your movement is a EB1197 ?  And don't think the problem is in the mainspring or the barrel. It's the cannon pinion that is loose and needs to be tighten up. 

Or find a better one that works better. 

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&EB_1197

Cannon pinion on this looks something like this. 

[clockboy]

 I seem to remember servicing a watch movement with that style of barrel/wheel set up. If my memory is correct this set up requires a certain amount friction to drive the wheel. The mistake I made was to clean & then lubricate which reduced the friction required. I had to give it a light tap with a closing punch to give it back the friction required.

[szbalogh]

No no, the OP has right. The clutch here is on the barrel. Its a Roskopf-type solution.

And Clockboy is also right, one can tighten it with a light tap to increase friction.

 

Edited October 5, 2017 by szbalogh

[clockboy]

5 minutes ago, szbalogh said:

No no, the OP has right. The clutch here is on the barrel. Its a Roskopf-type solution.

And Clockboy is also right, one can tighten it with a light tap to increase friction.

 

I must say it's just a poxy design.  

[rogart63]

There you see. Not always right

[richard]

Success, the light tap treatment has worked, infact I'm a bit worried it may be too tight. We'll see. I think just a bit of hard hand pressure, with the right stake, would have done the trick. Thanks everybody for your help and replies. Richard. 

[Folkvisor]

I had a similar problem with a 6497-2. I used a staking tool to give it a tap - actually a few taps. I was surprised how hard I actually hit it. But it works beautifully now.