I have not got that much experience in watch repair but the ones that I have done, run good. My problem is now that the last few all seem to come up with the same malfunction. They run slow or sluggish and or stop at different positions. Face up or face down and vertical at different positions. I can see that the hairspring is rubbing on the cross brace of the balance wheel on some. What am I doing wrong that causes the hairspring to get catty wampus? Could letting the balance wheel hang from the bridge be part or all of the problem? Some times the Mainspring seems not to have enough power to turn the train, yet it is wound good and has lots of tension. If I pull the barrel out and use a screwdriver or my finger to create the needed tension on the Minute wheel it will run.
All answers are appreciated.
Patrick 1616

Almost all problems of this nature are going to be in one of two areas...the balance or the train, sometimes both, IMO. I use isolation as a means of determining where problems lie. Once apart and everything has been cleaned and examined, I focus on the balance. The upper and lower cap and hole jewels have to come apart and be cleaned, oiled and examined carefully for cracks or breaks or severe divots in the cap. The staff pivots have to be mirror shiny and smooth and straight. The roller jewel has to checked for tightness and straight. The hairspring should not have any corrosion and not have unusual kinks in it. Once all that is done, I assembly the balance cock and balance wheel, making sure I get the outer coil between the regulator pins. If you put the stud in place and then try to put the hairspring between the pins you will probably knock the hairspring out of whack. Next I put the balance assembly on the watch by itself...remember isolation and set the balance in motion with a twist of the wrist. The balance wheel should swing smoothly in all positions and come to a gradual stop with no jerky motion. I like to see the balance oscillate for at least a minute before it stops. A very small movement of the plates should rock the balance freely. While stopped look between the banking pins in a line thru the pallet hole and check that the roller jewel is centered between the pins. If not turn the hairspring collet on the staff till it is centered. This puts the watch very close to being in beat. Once you are happy with the balance assembly, remove it from the plates and set it aside under a glass cover for protection. Next move on to the train. With all the holes cleaned (jeweled or otherwise) and any additional cap/hole jewels disassembled and cleaned and all the pivots and wheels carefully cleaned and examined, assembly the train. Assuming you have already removed the mainspring from the barrel and cleaned and lubed it, put it back in with the train...leaving the pallet out. Now with one click of winding watch the escape wheel for smooth turning and if the mainspring is new or in very good shape, the escape wheel should stop and run backwards just a bit. Check your pallet stones for chips on the faces and that they are tight in their settings, check the pivots and put it back in. Wind the watch a few turns and with a pin, gently move the pallet fork back and forth and look for a nice snap in both directions. Put the balance back on and the watch should take off. After a short dry test, lube the rest of the pivots. Please note...this post is meant to address balance and train problems only, not a tutorial on cleaning and servicing.

For that you can't find anything better than Chris Abell's checklist here.

Roger, Thanks. There are two things you mentioned that I am guilty of. One stems from a advanced case of CRS and the other is a new lesson and a welcome one. I totally forgot the back spin and I have been putting in the stud before I inserted the spring between the pins. I can imeadiently picture how this would force (Bend) the spring in a position to rub on the balance cross bars and where it would bend it. I'll have to look see if perhaps I can fix some of them now.
Thank you for the lesson.
Patrick 1616

Some good lessons here.
I just cleaned a Hamilton 18s that didn't run. All I could find wrong was that the mainspring was wound up tighter than a banjo string. So I figured it was just dirty.
Well, I just completed it and reassembled, only to find that it still won't run. Upon closer examination I see that the hairspring is cocked and rubbing the crossarm on the balance wheel on one side.
So, next step, check the hairspring collet and see if it is seated properly?

Listen to Roger, gentlemen. He's fixed the problem(s) of every watch I've ever sent him, and even discovered a few that I was unaware of.

He is careful and patient, misses very little, and checks everything on the way out of the watch.

Still have the hairspring problem. I've had this apart now a couple of times. If I puff some air on the balance wheel it runs. The overcoil on the hairspring about half way round from the stud appears to be pushing down on the rest of the hairspring coil and applying pressure on the cross arm of the balance wheel. It doesn't appear to be bent in any way but I can't figure out how to correct it.
Any thoughts or ideas greatly appreciated.

Dave,
Look at where the hairspring is pinned to the collet..Make sure it is level and not bent up or down..

Also have a look at the hairspring stud to see if it is still at right angles to the hairspring.

I have had a few that aren't and when you replace the balance it forces the spring down towards the balance arms.

Not getting the spring through the curb pins before fixing the stud on the cock, and perhaps removing the cock with the spring attached could do this. Don't ask me how I know...

Regards

Peter in Oz

Thanks Guys,
Third time's a charm. I didn't really find any problem with either end of the hairspring attachment. But, I do think the problem was that the alignment pins were fairly tight and the hairspring was caught at the very bottom and needed to go a little deeper between the pins. The outer end of the hairspring was pushing down on the outer turns of the rest of the spring.
Problem solved and she's running!

Did I say I love this forum? It's times like these that make you really appreciate the wisdom of the group.

Learned another lesson on this watch too. Ready to put the dial back on and all of the dial screws are missing! (Found them in the jar of watch cleaning solution). The ultrasonic cleaner vibrates the screws out unless you tighten them up or remove them before cleaning!
This is the best picture I can get with my phone camera. My digital camera was stolen! Camera recommendations? I need a new one.
By the way this a Hampden not Hamilton as I previously stated.
It's a 3 Ball Hampden with original Dueber case.