Elgin PW-which way to loosen ratchet wheel?

[Lc130]

Hi All,

I'm just learning the very basics at this point.  I've picked up an Elgin grade 345, 12s PW on ebay.   Here's more info: https://pocketwatchdatabase.com/search/result/elgin/20602697/movement

It runs for maybe a minute at most before stopping.  I'm attempting to disassmble and clean it as it's terribly dirty.  

I didn't get far.  At the moment, I'm not able to remove the stuborn screw on the ratchet wheel.  My question is whether it's lossened clock or counter clockwise?  I've read that ratched wheel screws can go either way.  Also, is there some type of screw treatment (oil, etc) that would help?

Many thanks

Charlie

 

 

 

 

 

[vinn3]

before you apply too much torque;    keep asking till you get and answer on the screw direction.  if you have already tryed, its sprobably too tight or rusted.  use penitrating oil and heat before you try again.  vin

[Chopin]

I hope you have a good set of screwdrivers that were sharpened and prepared accordingly. (google it as there are guides for that as well)

I've had success by pushing down on the screwdriver with a bit of force but be careful not to slip the screwdriver tip and scratch or even damage something. (only attempt as a last resort, perhaps)

Those screws can indeed go both ways...

[vinn3]

i have recieved several with 1/2  or no head at all.   vin

[JohnR725]

Ratchet wheel or crown wheel? Ratchet wheels on American Pocket watch is a standard screws it's the crown wheel that's usually left-handed.

[Lc130]

Fletcher's book "Watch repair as a hobby" has this:  "Now remove the ratchet wheel by unscrewing the screw at its centre; this is either right-or left-handed according to the whim of the maker."

Neither the screw at the 6 o'clock position (crown wheel?), nor the screw on the wheel to its left (winding/ratchet wheel?) will budge.  Not sure of the direction of either.

Charlie 

[vinn3]

penitrating oil and heat.

[Lc130]

OK. I believe that JohnR725 has it right (or left!).  I found this thread at NAWCC https://mb.nawcc.org/threads/ratchet-wheel-screw-always-reversed-from-direction-of-turn.119163/  And this video of another Elgin grade PW.  This repairer specifically notes that the crown wheel loosens to the left.

Thank you John!

 

[Lc130]

I mean the right!

[vinn3]

you have a 50 - 50 chance of getting it correct.

[Watchfixr]

If you look at the picture you attached, the crown wheel will rotate counter-clockwise when the stem is turned to wind the mainspring. It will, in turn, cause the ratchet wheel to turn clockwise. In this particular case, the crown wheel screw should be a left hand thread and the ratchet wheel screw should be right hand thread, If the crown wheel screw were right hand thread, the winding motion would tend to loosen the screw. Same rule applies for the ratchet wheel screw.

All bets are off when it comes to Swiss watches. I've seen it go either way at the whim of the designer. If I'm not sure, I put a little pressure on the screwdriver in either direction to see if I can detect the screw starting to loosen. With a little luck you can usually get the screw out in the correct direction without shearing off the screw head.

[Lc130]

Watchfixr,

Thanks very much.  I'm still waiting for the larger screwdrivers I've ordered to arrive.  I'll let you know how it works out.

 

[Lc130]

Yes, crown wheel is reverse thread.