AS 1187 pallet fork sticking.

[markr]

After cleaning balance worked fine. Removed and assembled watch.  VERY low amp.  Balance counter clock was fine but move balance clockwise and wood stick after about 90 degrees.  Balance buy itself good.  Balance with fork bridge no fork good.  Add fork and sticks again.  Any Ideas? Sorry for bad photos.

[ifibrin]

28 minutes ago, markr said:

After cleaning balance worked fine. Removed and assembled watch.  VERY low amp.  Balance counter clock was fine but move balance clockwise and wood stick after about 90 degrees.  Balance buy itself good.  Balance with fork bridge no fork good.  Add fork and sticks again.  Any Ideas? Sorry for bad photos.

Do you mean that without the pallet fork, but with the pallet bridge, the amplitude is fine? If so maybe the guard pin is rubbing against the crescent, or the shock block?

[Klassiker]

Is the central arm of the pallet fork slightly bent and / or twisted? I suspect interference between the guard pin and safety roller, or the impulse jewel and one of the horns. Do you have equal amounts of lock on the pallet stones?

[Nucejoe]

 I concur with Klassiker, fork horn looks bent.

I would try streightening it and hope for the best.

Regs

 

[watchweasol]

I would agree the whole pallet horn is not straight, I have had this before and managed to straighten it out.  Made a little jig to hold the fork and gently re aligned the head.  be careful do it by degrees and re try after any adjustment.

[markr]

Thank everyone.  I'll try to tweak the horns tonight after work.  I'll let you know how it turns out.

[markr]

It's alive.  After straightening the pallet fork the exit jewel would not release the escape wheel so a tweak of a pin and it's up and running.  I'll let it run tonight and adjust tomorrow Thanks for all the help.