Koma Diana

[Tony3900]

My Kundo is running great, now for my Koma Diana. I have taken the movement apart replaced the mainspring cleaned and oiled the movement and a new suspension spring. But I just cannot get the movement to run longer then about 10 minutes. I read in the Horolovar 400 Day Clock book that they had put a 14x25 spring in the later movements and had to increase the barrel and arbor lengths. Is there a stronger 12x spring that would fit in my barrel. Any suggestions on how to get this clock running? ThANKS

 

[KurtinSA]

Not running for longer than 10 minutes points to an escapement issue or too much friction in the going train. I think you have to sit back and check all the usual suspects. Throwing more power at it isn't really the way to go, although that's what Koma did. As for another main spring besides the 12x25 you're running, nothing seems to be suitable. There's a 12x24 meant for a 24mm diameter barrel...if you used that, the barrel would be too open although the spring length is quite a bit short. It is thicker which might mean more power but would the spring fit? There's a 12x32 meant for a 32mm barrel and nearly double the length of the current spring. So, it probably wouldn't fit in the barrel...it is thinner which usually means less power. Any of these springs probably means it wouldn't run for anywhere close to a year. Best to figure out what's wrong with your current set up.

Fork to tine clearance? Position of fork on suspension spring? Locks/drops OK? In beat?

I've found miniature/midget clocks to be finicky. Also, yours in pin-pallet...another tough one to crack. IMO.

Kurt

 

[Tony3900]

Not running for longer than 10 minutes points to an escapement issue or too much friction in the going train. I think you have to sit back and check all the usual suspects. Throwing more power at it isn't really the way to go, although that's what Koma did. As for another main spring besides the 12x25 you're running, nothing seems to be suitable. There's a 12x24 meant for a 24mm diameter barrel...if you used that, the barrel would be too open although the spring length is quite a bit short. It is thicker which might mean more power but would the spring fit? There's a 12x32 meant for a 32mm barrel and nearly double the length of the current spring. So, it probably wouldn't fit in the barrel...it is thinner which usually means less power. Any of these springs probably means it wouldn't run for anywhere close to a year. Best to figure out what's wrong with your current set up.

Fork to tine clearance? Position of fork on suspension spring? Locks/drops OK? In beat?

I've found miniature/midget clocks to be finicky. Also, yours in pin-pallet...another tough one to crack. IMO.

Kurt

Thanks Kurt shall continue to investigate. I will get it eventually.

 

[Schatznut]

All the usual suspects in 400-day clocks are there with a vengeance in the miniature movements, and I think you're stuck with the mainspring you have. Did you polish the pivots? This is particularly important when dealing with a movement such as this one that has minimal excess power. Is the beat set correctly? With minimum supplemental arc, the beat has to be spot on to get maximum running time from it. There's really nothing magical about the pin pallet escapement; it's just a bit different than the Graham. I agree with Kurt - go back to the basics and make it absolutely perfect. I have one like yours that runs well - I wind it during daylight savings time changes, so I know it will run at least six months on a winding.

After polishing the pivots, I find that installing one wheel at a time and checking for friction, straightness and end float is a worthwhile exercise, followed by two at a time looking for any binding or interference, and so on, until the whole movement is built up minus the anchor. Then the two-click test is a good indicator of how well the movement is set up. If it goes into motion with no more than two or three clicks, then you are assured the works is set up well and has minimum friction. If, after installing the anchor, the clock still stalls, that's indicative of a problem in the escapement, such as beat, position of the fork, clearance between the fork and anchor pin, or a damaged suspension spring.

One final thing - from my experience, all Komas are really sensitive to the tightness of the hand nut. Too tight and they stall. Too loose and the minute hand just drops uselessly to the "6" position. And the range between the two extremes is small. You might start by just loosening the hand nut and see if the clock runs, even if the hands are not advancing.

Good luck - this is a cute little clock that is enjoyable to watch running alongside its bigger cousins.

 

[Wayne A]

These miniature pin pallet clocks are marginal on power so everything needs to be about as good as you can get for them to run well. So thats polish the pivots, smooth broach the piviot holes, clean and lube the mainspring.
Pin pallets have one anchor adjustment and its usually not enough to get the entrance and exit pallets the way I'd like them to be. On mine I have the entrance set to drop as close to the edge of the EW tooth without overriding, the exit ended up a little deeper but its good enough. I like to remove the rough surface of the impulse faces of the EW and coat them with dry film teflon, and for the pins apply a very tiny bit of synthetic oil that's just enough to coat them. Here is a VIDEO of what my escapement looks like. Setting the beat is important and do the setup with about 1 turn on the mainspring having at least 20deg overswing. I did brush a few pivots, don't like to see any slop. The higher than average 15bpm is interesting to watch.


Wayne

 

[Tony3900]

All the usual suspects in 400-day clocks are there with a vengeance in the miniature movements, and I think you're stuck with the mainspring you have. Did you polish the pivots? This is particularly important when dealing with a movement such as this one that has minimal excess power. Is the beat set correctly? With minimum supplemental arc, the beat has to be spot on to get maximum running time from it. There's really nothing magical about the pin pallet escapement; it's just a bit different than the Graham. I agree with Kurt - go back to the basics and make it absolutely perfect. I have one like yours that runs well - I wind it during daylight savings time changes, so I know it will run at least six months on a winding.

After polishing the pivots, I find that installing one wheel at a time and checking for friction, straightness and end float is a worthwhile exercise, followed by two at a time looking for any binding or interference, and so on, until the whole movement is built up minus the anchor. Then the two-click test is a good indicator of how well the movement is set up. If it goes into motion with no more than two or three clicks, then you are assured the works is set up well and has minimum friction. If, after installing the anchor, the clock still stalls, that's indicative of a problem in the escapement, such as beat, position of the fork, clearance between the fork and anchor pin, or a damaged suspension spring.

One final thing - from my experience, all Komas are really sensitive to the tightness of the hand nut. Too tight and they stall. Too loose and the minute hand just drops uselessly to the "6" position. And the range between the two extremes is small. You might start by just loosening the hand nut and see if the clock runs, even if the hands are not advancing.

Good luck - this is a cute little clock that is enjoyable to watch running alongside its bigger cousins.

Thank you, in the process of doing just that with each wheel. Did find a slightly bent pivot. Hopefully that was it. Again thank you.

 

[Tony3900]

These miniature pin pallet clocks are marginal on power so everything needs to be about as good as you can get for them to run well. So thats polish the pivots, smooth broach the piviot holes, clean and lube the mainspring.
Pin pallets have one anchor adjustment and its usually not enough to get the entrance and exit pallets the way I'd like them to be. On mine I have the entrance set to drop as close to the edge of the EW tooth without overriding, the exit ended up a little deeper but its good enough. I like to remove the rough surface of the impulse faces of the EW and coat them with dry film teflon, and for the pins apply a very tiny bit of synthetic oil that's just enough to coat them. Here is a VIDEO of what my escapement looks like. Setting the beat is important and do the setup with about 1 turn on the mainspring having at least 20deg overswing. I did brush a few pivots, don't like to see any slop. The higher than average 15bpm is interesting to watch.


Wayne

Thank you Wayne the video is very helpful. Did as you suggested and smooth broach the pivot holes.

 

[MartinM]

All of the above is great advice. Also make sure the tension spring for the motion works is installed correctly.

 

[Tony3900]

I think I might have it. Fingers crossed.

 

[Schatznut]

That's a cute one! Hope you've got it sorted!