Which way to turn out ratchet wheel screw?

[szbalogh]

I have a broken screw in this Stowa pocket watch. Bought alumn today to dissolve it but its in the barrel arbor.

Will make a screw cut in the end and try to turn it out but which way to turn?

Edited April 26, 2016 by szbalogh

[Marc]

My guess would be that it is a normal right handed screw, so turn anti-clockwise to remove.

 

[matabog]

+1

[Tiktok]

I would also guess anti clockwise, I presume the screw head only has one slot in it and not any other lines across the head to indicate it is the other way?

Have you tried sitting the screw head back on top of it and pressing down with a screwdriver to try and unscrew it, sometimes it will bite and unscrew, make sure you check and correct the barrel arbor end shake in the barrel though afterwards and the end shake between the jewels because both could be altered a bit messing about with it.

[szbalogh]

Thank You mates!

I dont have the screwhead. This movement is similar and has normal screw here. I will try ccw then 

 

[vinn3]

some of those are left handed thread,   which  means you  turn to the right to loosen it.  if the  head is snapped off,  it  was turned the wrong way.  best cosult a jeweler.

[Geo]

32 minutes ago, vinn3 said:

if the  head is snapped off,  it  was turned the wrong way.  best cosult a jeweler.

It may have been turned the wrong way, but it might also have been over tightened to the point where the screw had been stretched beyond its elastic limit and the head snapped off.  It may also have been rusted in and the head broken off when attempting to unscrew it.

If you do take it anywhere for advice, take it to a watchmaker not a jeweller.

If you study the break with a high power loupe, you might just see what direction the thread is.

My money is on it being a right hand thread because there is no need whatsoever for it to be left hand.  I say this because the ratchet wheel is fitted onto a square and therefor cannot rotate in any direction relative to the arbour to impart a slackening effect to the screw.

[vinn3]

ill  stick with my guess  the spring barrel screw is left hand thread  and was turned to the right.  cheers

[szbalogh]

Thank You guys! 

I will look at it under the microscope tonight. 

[szbalogh]

Ok, here is my best picture of the screw:

Seems a normal thread to me.

I was drilling and grinding all day long and my Frankenstein lathe is born

Now i can mount the barrel arbor for turning:

First i will try to turn out the remaining screw with my graver. If it wont work i can make a center hole for drilling. Or sgould i make a 0.2mm cut in the arbor head and with that in the screw and try to screw it out? What method would You choose?

 

[szbalogh]

Managed to drill through the screw with a 0.8mm microdrill. Surprisingly, it had only 1-1.5mm long broken piece and many empty threads under it. 

Now, how can i get the remains of the screw out from the first 3-4 threads?

 

[jdm]

20 minutes ago, szbalogh said:

Now, how can i get the remains of the screw out from the first 3-4 threads?

Try a dental tool with a curved tip.

[szbalogh]

1 minute ago, jdm said:

Try a dental tool with a curved tip.

I dont have such but try to make one from a needle. Thank You! 

[ro63rto]

Jewellers tap and die set?

[szbalogh]

6 minutes ago, ro63rto said:

Jewellers tap and die set?

Unfortunately, i dont have a tap and die set. Only a M1.2 die. 

[ro63rto]

Got mine for £5 from ebay.

[szbalogh]

9 hours ago, ro63rto said:

Got mine for £5 from ebay.

I found only for 16 GBP. Can You please give me a link for a cheaper? 

[bobm12]

How about dipping in some oil (3 in 1 or something) and later scraping with the needle? Would it work? Any way to use the lathe (the new awesome one you just created?) while scraping with the needle? Just a though...

[szbalogh]

1 hour ago, bobm12 said:

How about dipping in some oil (3 in 1 or something) and later scraping with the needle? Would it work? Any way to use the lathe (the new awesome one you just created?) while scraping with the needle? Just a though...

I did it just like that  Unfortunately it didnt came out. Finally one size bigger microdrill (0.9mm) did the job. However, the first 3-4 threads are now about half hight. Bu who cares, there are a lot more under it, i just need a longer crew. 

[bobm12]

And Loctite!