Having trouble removing the barrel on this old 1Mchz movement

[DoctoralHermit]

Hello again! I'm having trouble removing this barrel from the plate (is it called a barrel plate?) of this old Mockba 1mchz russian movement. The screw on the top is just for winding the watch... it doesn't seem to loosen the barrel from the plate. Any thoughts?

[Nucejoe]

It is called barrel lid. 

Just keep the ratchet wheel from turning as you undo the screw.

Best would be to soak the whole parts you show in first pic, in naphta overnight, naphta penetrates the thread of barrel arbor, this would reduce the risk of the head popping of the screw.

Regards joe

[Nucejoe]

Just to make clear, putting penetrating oil on top of the screw would do little or no good as the oil is unlikely to seep into the barrel arbor thread.

Submerge the whole barrel- bridge in naphta or coca cola for hours, this will greately  reduce the risk of the braking the screw. 

Be funny if it unscrews easy, no need for any of my lecture.

Best wishes 

[watchweasol]

Hi Just make sure its not a Left had thread.

[nickelsilver]

That's the ratchet wheel. You will need to remove the screw, block the wheel with a piece of pegwood or toothpick so you can unscrew it. 9 times out of 10 they are regular right hand thread, but as watchweasol said it could be left hand. Try gently both directions, increasing your force till it goes. They upside of doing it like that is if the thread is a little stuck, often tightening it slightly will help it loosen. Seems odd but it works.

[DoctoralHermit]

On 7/22/2019 at 11:51 PM, Nucejoe said:

It is called barrel lid. 

Just keep the ratchet wheel from turning as you undo the screw.

Best would be to soak the whole parts you show in first pic, in naphta overnight, naphta penetrates the thread of barrel arbor, this would reduce the risk of the head popping of the screw.

Regards joe

Thank you! Before, I was holding the barrel in place and turning the screw, but I think it was still turning the ratchet wheel. When I held the ratchet wheel in place instead, it worked!

[MrRoundel]

While it might not have made any difference here, I generally loosen both the crown wheel and the winding wheel screws while both are in place. If I need to, I can place a piece of pointed pegwood where the two wheels meet, in order to get good hold. I then remove them. Good luck on the watch.