Sorna jump hour barrel help

[jameswrx]

Afternoon people. 

Have a quick question, does this barrel assembly split like I assume?  ie part the wheel off the hub and then split the barrel?

Also, how tight should the wheel be on the hub?  It feels extremely tight to spin, assumed it should move with moderate pressure.

 

Edited May 16, 2017 by jameswrx

[noirrac1j]

What's the caliber on this watch? These have no cannon pinion so the direct-drive gear (usually powers the sweep second hand if it has one) is attached to the barrel as one piece. Be careful to avoid oiling  anywhere near that attached gear because the watch will run, but not keep time because of slipping. This is also the gear that engages to set the time, so they are prone to loosening and it is good if it's tight. I'll keep an eye on your post.

JC

Edited May 16, 2017 by noirrac1j

[jameswrx]

Thanks JC. There's not a lot of markings going on, just says sorna watch SA DE on the main bridge and 2889 on the case back.

As you guessed, it has a centre second hand.

The whole thing is literally dripping in oil! 

I wanted to try and clean out the barrel as it's full of oil.

[noirrac1j]

Remove the barrel cover (with the gear attached) and place the entire thing in lighter fluid, then let dry. There should be a good amount of friction between the gear and the barrel cover. Is it a pin pallet? Jeweled? Try to get a picture of the movement if you can and post it. 

 

J

[noirrac1j]

Just to clarify, push on the arbor from the other side with the flat side of tweezers and the entire barrel cover including the gear should come off.

JC

[jameswrx]

That's good, thanks. Glad I don't have to remove the gear wheel. Thanks for the help.

 

yes pin lever pallet fork, it's a massive one jewel movement.

[jameswrx]

Sorted the barrel and train gears all cleaned and sorted but I couldn't see how to split the register side?

It is a very basic movement, it says 21 j on the dial but there's only one jewel on the mvt.  Not sure what the deal is (changed or dial lies) 

Anyway I couldn't see how to split the register side but the issue was the balance was all bunched (which I sorted) and I put the movt back together and it runs ok but the register side seems to show the time has stopped.  I had it on the timegrapher with the sound on for a couple of hours and it didn't miss a beat but the register keeps displaying the time behind.

Is the register side serviceable? I couldn't see an obvious way it splits.  The centre part doesn't have a clip securing.

[noirrac1j]

Hello,

"...but the register keeps displaying the time behind." I am guessing that by register you mean the three dials that comprise the minute, hour and date. OK, first this may be that the barrel cover gear is slipping on its arbor and not transmitting enough power to turn the time dials. That smallest dial with the two oval openings is where you place either 1mm screwdrivers or lever-typr hand removers: one on either side and pry it up carefully. It won't bend or break if you get good placement and press gently upward with increasing pressure. I did a similar watch not too long ago:

 

When you get under there, be very careful with the springs and make a note of the orientation of the plates. There isn't much that will need oil/grease under there except the little hour and date levers that hold the wheels in place after they've rotated.

 

J

[jameswrx]

Thanks again for your help.  If there's not much under there that could cause a slowing issue then I may leave that side.

I think (as you say) the barrel gear may be the issue.  The gear was relatively easy to turn, when I say easy now I originally thought it was stiff and maybe needed to turn in a sort of clutch way for adjusting the time with the crown when I first saw it.  So I now say easy in light of it really needing to be solid (if that makes sense haha)

So it should be completely solid on the arbour.  I'll have to see what I can do to try and fix it tight.

[noirrac1j]

Hello, The gear needs to turn when setting time, but needs to have enough friction (and power) to drive the hour and minute wheels. The seconds (gear) is directly coupled so that will always run. I'm in the lab now, but will follow up soon on how to fix that loose barrel cover drive gear.

 

J

Edited May 19, 2017 by noirrac1j

[jameswrx]

Ah right, so that was correct what I assumed about time setting.  Maybe it isn't that then as I can't imagine the register side would put enough drag on the wheel to slip it on the arbour.