Un-jeweled lever escapement balance woes

JeffG

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Does this look right?
IMG_9283.jpg

This is the balance shaft from the New Haven wind up clock pictured below.
It was included as a freebie in another purchase due to the rust-stained dial, which I scanned, photoshopped, and reprinted (pretty proud of that one). The pivots are good, the hairspring seems ok, the hairspring-side cone could be sharpened, and the cups are poor, but the balance rotation seems jerky, off beat, and only about 45˙ of rotation.
Could the impulse pin and notch being out of alignment be the problem, or is that not as big a deal as the cups needing attention?

IMG_9286.jpg IMG_9288.jpg
 

R. Croswell

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...... the hairspring-side cone could be sharpened, and the cups are poor, but the balance rotation seems jerky, off beat, and only about 45˙ of rotation.
For sure it won't run properly if the pivot cups are "poor" and the balance staff points are worn down. You may have multiple issues, but I would begin by repairing the known defects then reassess the situation. It should have 270 to 360 degrees total rotation if it is in good condition.

RC
 

JeffG

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...I would begin by repairing the known defects then reassess the situation.

RC
I have sharpened and polished the points, polished the cups as best I could (weren't as bad as I thought), polished pivots, smooth-broached holes, cleaned/lubed mainspring, and realigned the pin and notch on the balance shaft while I had it apart. Put it back together hoping for the best, but only got about 90˙ of rotation. The hairspring does not dance back and forth within the regulator, and it seems out of beat.
I will tinker further when I get a chance and report back- possibly with slo-mo video.
 

Dick Feldman

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You cannot expect satisfactory operation of any style escapement without sufficient power.
Could it be you are chasing the symptoms of low power rather than the cause?
More than likely those movements are lacking power due to friction due to wear due to long use.
JMHO
Dick
 

JeffG

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Could it be you are chasing the symptoms of low power rather than the cause?
JMHO
Dick
Yes. That could absolutely be the case.
It has managed to run for 20 hours now, and has increased it’s rotation to closer to 135 degrees.
Is there a general flow chart for how to set up these lever escapements?
 

R. Croswell

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Yes. That could absolutely be the case.
It has managed to run for 20 hours now, and has increased it’s rotation to closer to 135 degrees.
Is there a general flow chart for how to set up these lever escapements?
You have two obvious problems with the escapement, perhaps more, but 135 degrees is better than 45 degrees, so you are getting closer.

1) The inner most coil of the hair spring is attached to a split brass collet that is pressed onto the balance staff. With no power applied the drive pin and lever should be at rest in a "neutral" position. You can adjust this by rotating the split collet. You can place a tiny screwdriver in the split to loosen the tension and rotate the collet. This should be close enough to run. If you get it in perfect beat, it may have trouble self-starting. Once you get 300+ degrees of rotation a slight out of beat won't be noticeable. Obviously, where the hairspring is pinned will affect where the balance rests and the beat. If you find it necessary to pin the tail longer or shorter for regulation, you will need to make a corresponding adjustment in the split collet to bring it back in beat.

2) If the "hairspring does not dance back and forth within the regulator", then the outer coil of the hairspring is shaped incorrectly and is pulling the hairspring off center. The last 1/3 of the outer coil is formed such that it is further away from the next coil. If you unpin the hairspring and rotate the balance wheel, the tail of the hairspring will slip into the regulator slot without help.

3) You didn't say how you repointed the balance staff. If the new point is even slightly off center, the entire balance will be out of balance. You can test this with the hair spring removed and just the balance between the cups (no lever) and look to see if the balance has a heavy side that always stops "down".

4) When the balance staff point is as worn as shown in the picture, it is unusual for the balance screw cup to not be significantly damaged. There are often divots where the point rested, and it is almost impossible to effectively polish out these defects and remove get every bit of debris from the tip of the cone. One really needs a microscope to get a clear view - it can be frightening.

You may indeed still have a power problem, but you can't get satisfaction by overpowering an escapement with problems.

There are several books that explain this type of escapement.

RC
 

Dick Feldman

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Let us approach this situation from a little different slant.
Most of those alarm clock type movements were not meant to be repaired. When those movements failed, there was usually more than one cause. Because of the low initial cost of that type movement, proper repairs were/are out of the realm of financial reasonableness. Clocks are complicated machines and the series of "happenings" must happen in the same order every time. That is the first set of realities you face.
Clock repair is not meant to be a game of guessing. There are specific procedures for trouble shooting clock movements. Trying to trouble shoot a clock over the distance of a thousand miles or so (or the Internet) is difficult, if not almost impossible. Here is a second set of realities.
If you would like to be a competent clock repair person, you must study and a good deal of experience will help. A good approach to repair the clock you have would be to find a mentor that has experience and willingness to help you along. The NAWCC chapters throughout the world are a good place to find a mentor. A good publication for general clock repair is This Old Clock, by David S. Goodman. That should be available through your local library or can be purchased on eBay or Amazon.
That is how I feel,
Dick
 

RJSoftware

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The roller pin is not aligned with the notch for the safety dart. Needs to be center. See first pic. Hold roller that has safety dart slot, firmly with pliers. Twist balance wheel by rim till roller pin is centered to safety dart slot. The lever fork has a safety dart that prevents fork from flopping over to wrong side, causing a lockout. This normally doesn't happen unless clock is jarred or sometimes when winding. The only time lever fork can pass to opposite side is when balance wheel is in correct position and safety dart notch allows passage.

Being not centered like that the dart will bump the edge, slowing down impulse.
 
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JeffG

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R. Croswell said:
1)If you find it necessary to pin the tail longer or shorter for regulation, you will need to make a corresponding adjustment in the split collet to bring it back in beat.

Thank you! This is exactly the kid of instruction I was hoping for.

2) If you unpin the hairspring and rotate the balance wheel, the tail of the hairspring will slip into the regulator slot without help.

It does not currently. Uh oh. It passes a bit outside of the regulator.

3) You didn't say how you repointed the balance staff.

I put it in a lathe and polished it with 2K and 3K grit sandpaper on popsicle sticks. Watched the wear marks in the paper through a microscope to be sure I was keeping the paper mostly flat to the cone.

4) One really needs a microscope to get a clear view...

The cups were not as bad as I thought after a good cleaning. This is after cleaning, before polishing, through a 20x stereoscope
IMG_9297.jpg
I jammed a Dremel polishing tip with rouge in there and got it well shiny, if not sharp.

You may indeed still have a power problem, but you can't get satisfaction by overpowering an escapement with problems.

Hear, hear!

There are several books that explain this type of escapement.

RC

IMG_9297.jpg
 

JeffG

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-Most of those alarm clock type movements were not meant to be repaired.
-If you would like to be a competent clock repair person, you must study and a good deal of experience will help.
-A good approach to repair the clock you have would be to find a mentor...
Thank you for your reply and reality check.
As I said, this clock was added in to another purchase for free due to it's rusty dial. In true cart-before-the-horse fashion, I worked on the dial first. I think it came out rather well.

IMG_9318.jpg
The case is also in pretty good shape with the gilding only really worn on Cupid's rear- presumably from a previous owner's wishes for luck. Given the dial and case, I decided to see about getting the movement running just to gain a little more experience. I have read a few books: Conover, Penman, Goodman (only 1 page on lever escapements), et al but nothing beats hands on experience. Which is why I'm working on and learning from this movement.

Unfortunately, in my case, a mentorship and NAWCC chapters are at a minimum a 3 1/2 hour flight away. I am literally on an island unto myself, which makes the fine gentlemen and women on these forums my de facto mentors. So thank you and I appreciate every bit of advice and instruction given to me and others within these posts.
-Jeff
 

JeffG

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The roller pin is not aligned with the notch for the safety dart. Needs to be center.

Being not centered like that the dart will bump the edge, slowing down impulse.
Thank you! That is what I suspected, but this is the first lever escapement I've really bothered with and wasn't sure if this was a non-issue or not. I suspect that the safety dart was bumping and causing the jerky rotation. I straightened it out while I had it apart initially and found an improvement. Hopefully some attention to the hairspring will lead to more robust rotation.
30+ hours now and still ticking away.
-Jeff
 

RJSoftware

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The hairspring looks ok.

Looks like if pinned at the terminal, keeping coils flat/even and no coil touching other coil, your good.

Next step is to make sure beat is correct.

So, imagine a raight line between the balance arbor/pivot tip to the lever arbor. When the balance is correct (in-beat) the roller pin will travel same distance on both sides of the imaginary line.

You adjust by inserting small flat head screwdriver blade into hair spring collet slot. With other finger roll carefully bale wheel while keeping collet stationary. The collet is friction fit to balance arbor so it will give. Try to be gentle and only move a tiny bit at a time. The brass collets are.delicate. Rest the hand with screwdriver inserted in collet gap on movement, on table. Roll balance with finger from other hand.

This may also improve balance motion some. Some say there should be slightly favored one side which helps facilitate starting balance rotation but this is not a watch or jeweled palettes.

The next is a trick with cone pivots like these. First only clean, do not remove metal from cup. The cone pivots can be lightly filed/burnished if need be The trick is to tighten the threaded cup till the point where balance won't turn freely Roll balance back and forth with finger a few times, then loosen cup till you feel just tiny hairs worth of slack, no oil.

Another issue with some fork levers is that some are two piece construction. The fork can be angled independently from pin pallets section. Make fork centered with line and one pin palette engaged.
Both pieces are friction fit to arbor.

If all conditions above are met and motion is still to slow, then yep, you probably got power loss.

You know you got power loss if it's real finicky, prone to stop. 2 test, Slow speed test and high speed.

For both test you will have to remove balance and lever. HST wind fully and listen/watch. If you hear a pop/click at regular intervals, try to visually sink sound to specific gear rotating. You can add excess oil to protect pivots during test. Also watch for deceleration/acceleration. A bent arbor/pivot will do that because it causes a gear mesh to tighten then loosen. The SST just wind a couple clic, let slowly unwind, then mark gears. Repeat. If SST same spot, check gear teeth there.
 
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JeffG

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Well, this is embarrassing.
Had some time to shoot a couple of vids and wow! The hairspring is conical, not at all concentric to the arbor, and the front escape wheel pivot is bouncing and robbing the impulse face of its impulse. I have some work to do, but I don't have broaches nor bushings small enough for the EW, so it'll have to wait.
P.S. the blob of solder on the lever is due to seeing a tiny crack beginning on its waist.
Humble pie videos to follow-




-Jeff
 

R. Croswell

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The important thing is that you identified the problems with the balance and escapement. Get that part fixed and it should run a lot better. Until you have experience with tiny bushings, you may be better to leave that well enough along. It is easy to make a bad situation worse! That outer hairspring loop isn't just pulled out - it should have a "crook" or dog leg at about 1/2 to 1/3 of the last loop to set it away from the other coils while maintaining the same curve.

RC
 

Mike Mall

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I've been trying to gain experience with lever escapements every chance I get. (mostly cheap alarm clocks)
Hairsprings can be a PITA to work with. But I've been getting much better at getting them back into proper position, and beat.
When the spring is conical like that, my experience is, it's the way the pin is slid in. I have been able to straighten them out by reinstalling it.
I can see your spring is a little malformed near the collet.
I really admire (envy) the watch guys' abilities to repair hairsprings.
 

JeffG

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When the spring is conical like that, my experience is, it's the way the pin is slid in.
Thank you for that!
I've been scratching my head on how to fix that. I know I got real close in returning the collet back onto the shaft exactly as it was. I assume it must have happened when I gave the pin a last nudge to seat it.

The important thing is that you identified the problems with the balance...
RC
I intend to attempt adjustment of the balance as soon as I can, but as discussed previously, will getting the balance in order give good results considering the loss of power from that wobbly EW pivot?
-Jeff
 

Thomas Sanguigni

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As RC mentions, take a step at a time. Get the coils to lay perfectly flat. Once you identify that, go after the dog leg. Right down the list. Once you get that laundry list done, let down the power, and put it in the best balance you can. You will probably surprise yourself.
 

RJSoftware

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ok, progress. I believe I see healthy oscillation. The slow-mo video effect was distracting for me.

What I look for is a coil body that seems to breathe like a lung. But, that's more for watch hair springs as small clocks tend to be a tiny bit more bouncy. The more bouncy, the poorer the oscillation, the worse.

People get the oscillation backwards. Also some interpretation of termi gets mixed up.

First, the farther the balance rotates, the slower time keeping, but the faster the balance spins. The less a balance rotates, the faster the time keeping, but the slower the balance spins.

This is because the balance pin rotates out of the levers range farther when rotation is healthy and piforspends more time away from the lever interaction which advances the escapement.

A weak rotation tick tacks back and forth more rapidly, the coil body doesn't have much of the appearance of breathing. So very little time is spent out of pin-lever engagement. The escapement speeds up and the timekeeping is too fast.

Here is another thought. The clock worked when it left the factory. The balance wheel and hair spring are a mated pair. The term is cd vibrated. So some factory worker spent time selecting just the right hair spring for that specific balance wheel cut the and shaped the coil to just the right amount so that the balance wheel would rotate the precise amount to keep good time.

So most likely you have a good hair spring.
 

RJSoftware

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ok, progress. I believe I see healthy oscillation. The slow-mo video effect was distracting for me.

What I look for is a coil body that seems to breathe like a lung. But, that's more for watch hair springs as small clocks tend to be a tiny bit more bouncy. The more bouncy, the poorer the oscillation, the worse.

People get the oscillation backwards. Also some interpretation of termi gets mixed up.

First, the farther the balance rotates, the slower time keeping, but the faster the balance spins. The less a balance rotates, the faster the time keeping, but the slower the balance spins.

This is because the balance pin rotates out of the levers range farther when rotation is healthy and piforspends more time away from the lever interaction which advances the escapement.

A weak rotation tick tacks back and forth more rapidly, the coil body doesn't have much of the appearance of breathing. So very little time is spent out of pin
 

RJSoftware

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ok, I see aother problem. Your hair spring has distortion pressure. Which is basically same as tightening up the hair spring.

True in the round and True in the flat.

True in the round:

The coils of the coil body, in a relaxed state, should have basically even distance between each coil. They should not touch or be closer together on one side.

The last coil has the dog leg. 2 bends, a 45 degree out and a 45 degree back. This is to create a section that the regulator loop controls.

Coil distortion, from error in the round, can happen from incorrect dog leg. By pushing or pulling hair spring body. Causing loops to bunch at one side, distortion = pressure = resistance.

Getting the dog leg right is critical. Infact, the hair spring in the regulator loop should bounce back and forth both sides of the loop when balance is rotating. Meaning, at rest in theoretical middle. But definitely not pushing/pulling.

Another issue about dog leg is that they should be constructed so the users full range of regulator adjustment doesnt distort spring. So if they mess around and full + or full -, it doesn't bend spring. A dog leg that poorly follows the regulator arc/sweep can get caught and mangled.

The terminal pin insertion can also effect true in the round. Basically this is common mistake from over insertion pressure. Put piece of toilet paper ball under balance. Pull the pin and tickle hair spring end to relax it's inclined position. Assuming you have no drastic bends the coils will relax. Turn the balance and tickle spring to pin at original pinned location if you can see evidence where original location was. If not do close to end.Th

Sometimes a simple bend at termination solves problem. Make microscopic adjustment.
 

RJSoftware

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True in the flat.

From the side view all coils should be on same vertical plane Flat.
Once again the terminal or the regulator loop can be the issue.

Out of flat is bad, but generally not as bad as out of round. Depends on amount of tension created. A coil can operate just fine with a small cone distortion. Just depends. But it's not neat, clean, proper.

So now we go where some fear to tread. Restoration of bent hairsprings.

Assuming we have deduced all possible dog leg, terminal pinning error the first step is to remove balance and spring. Make a mark on balance wheel where end of hair spring is. Use marker or tiny scratch like I do. I find marker is easily removed by accident.

Remove hairspringpzinzing up collet. This is your first major hurtle and many a hair spring can get destroyed here. The collet is friction fit, so it slides off. But you have to get reliably underneath and lverage something that wont bend the spring. Especially where the spring is inserted in the collet. On tiny watch balances a razorblade blde works alternating sides. Eventually giving room for tweezers. On yours you may initially have room for tweezers or even small needle nose.The

There are staking tools for this for watches but I don't think for clocks.

Dont try to twist off or use collet slot to turn off. The collet breaks easy.

Now with hair spring off placed on white sheet of paper, observe the following rules.

Is any coil touching or too far away? All coils shoould be evenly separate.

The rule for correcting out of round errors is to go 90 degrees before the error and correct there.

So you start from inner coil working outward. So, a coil is touching other coil, you go 90 in and bend coil slightly out. Many times having a small flat of tweezers is just enough to spread by simple squeeze. Conversely, for a coil too far out, you can grab at 90 point with tweezer and use pin to bend inward.

So, you get the body sweeter. Now you got the dog leg.

On a watch you have whats called the balance cock. It comes off and with it the regulator. So you can place on table upside down ad insert terminal pin. inserted in regulator loop. You can adjust the dog leg till the collet floats over center of bushing for balance. So this creates perfect dog leg that hair spring will relax in.

But on a clock you have to do your best to measure. Try not to do hard sharp bends. Only soft

, what if you got a massive cone, not true in the flat.

A trick. For a simple cone distortion, sometimes you can reverse it. Insert broach or tooth pick into collet at cone pointed side. Hold upright. With two fingers both sides of coil push downward to stretch coil cone in opposite direction. Use small incrementing to advance reverse action farther and farther till you get flatter resting state results.In essence the cone is a distortion that spread out over many coils. Often caused by a balance falling and terminal stuck. The weight of balance stretches spring forming a cone. This method attempts to reverse.

Other out of flat, say an individual coil. Apply 180 rule. Only now you need two tweezers. Hold one at the 180 before the apex of error and twist/bend so coil lays flat with other.
 
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JeffG

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The last coil has the dog leg. 2 bends, a 45 degree out and a 45 degree back. This is to create a section that the regulator loop controls.
Sometimes a simple bend at termination solves problem.
Thank you so much for taking the time to explain all of this!

Way back in post #1 there is a picture of the balance and spring as it was removed from the clock. There is a slight dogleg at about 6 o'clock on the outer coil, but the coil beyond the bends seems to go wide. If I'm understanding correctly, that end part of the spring (terminal piece?) needs to be coaxed back to being more concentric to the rest of the coils?

Geez, I'm so intimidated by this spring. I'm more confident with the tiny bushing than the tiny spring.
 

RJSoftware

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Concentrate on the hs body, the coil body. If you think something is causing distortion, then address that. Go soft use small increments.

Steady the arm by placing elbow on table, steady the wrist/hands on movement or work platform.

Use good light and magnification.
 

JeffG

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Thank you again!
Your posts #22 and #23 should be made sticky under the Hints & How-to's heading!
-Jeff
 

JeffG

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If you think something is causing distortion, then address that.
Here we go...

IMG_9366.jpg

I think, since there is no sign of an original dogleg, that my first attempt will be to flatten that kink at the bottom to see if that will bring the terminal bit back inline with the regulator and pin slot (represented here by a needle hole for reference).
I suspect that my own carelessness in disassembly may have introduced that kink, because the slight bend near the top seems to keep the coil more evenly spaced while making room for the regulator.
-Jeff
 

RJSoftware

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You know the expression "work hardened" , where metal becomes stiff and brittle. Anyway, just a heads up not to overwork (too many bends back and forth), repeatedly bending in one spot can break. Just a warning. Not saying you're doing that.

A good thing to do at this point is to establish (on the paper) the distance of the regulator loop from center a mark that on paper as a guide to bend your dog leg. A compass could help.

The regulation loop has an arch that normally doesn't match the hair spring curve. What you do is examine what arch path the regulation loop expects to travel from full + to full - and back. So the dog leg should extend past both extremes (full + and full -).

The dog leg can start 1/4 turn or more from termination. Make soft bend out then soft bend in. Use the pencilled mark of regulator loop from compass to determine where to bend back in.

The net result should be, the dog leg lays on line in perfectly relaxed state. With the dog leg portion the rides inside regulation loop being extended beyond full + and full -, no future owner can damage your work by tinkering with the regulator.

The re-install, making sure coil is correct direction, adjust coil end to balance wheel mark. You can turn the collet by inserting screwdriver in tiny slit, but be advised the collets do stretch and crack.

Then when you re-pin the termination, check regulator action, full+, full -, looking to see if any tension/distortion occurs. Do slowly as sometimes the loop can grab and bend spring.

Wind and test the motion. Looking at balance wheel pin travel on both sides of the imaginary line between balance arbor and the fork arbor.
(In beat). Adjust with screwdriver inserted in the tiny collet slit, using other finger to roll collet, as explained previous.

When you do first termination, do near end, unless you really have good memory/evidence where it was originally pinned. If it runs too fast and you pinned at end as far out as possible, you might have other problems, like weak power.

But if time keeping runs too slow your in luck. You can then in small advancements pin termination point further towards body. In effect shortening the spring (but never cut).

As you move termination point in either direction, you will need to adjust beat. But, I recommend after a few time checking intervals so you reduce collet fiddling/breaking. The clock can run fine enough out of beat to give you an idea of your progress. Once your happy. A couple minutes off a day, then set the beat.

The ideal conditions when terminating is to leave regulation loop in center and establish good time keeping with precise termination. Then regulator can be adjusted for things like temperature change..But hey, clocks are for fun too. So I don't expect perfection.

An old gal can run for hundreds of years. Long after we are dust.
 
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RJSoftware

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On the bends of hs in pic above, I would grip at top with tweezer tip and use needle to push inward just left side of hs to tuck curl in, to match other coil distance. Roll coil right 90 degrees and repeat at top again.

The idea being to get outer perimeter down to have clean even body so I could bend dog leg for the r-loop.

But if the loop is way out of the way, I might do with as is. The more you fiddle the closer it gets to breaking.

Looking at collet, just after the insert, I can see there could be more of a bend made there. To center it more with the body. But, it looks like "as is" is probably best, so I'd leave it alone.
 
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R. Croswell

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RJ offered a great explanation. Here's my attempt to illustrate it. Jeff, your "dog leg" starts out pretty good, but it needs to maintain a constant radius through the arc the regulator takes from fast to slow. At no point is the regulator allowed to pull the hairspring off center.

RC

hs1.jpg
 
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JeffG

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Here's my attempt to illustrate it.

RC
Thank you!
Here's my progress.
IMG_9368.jpg

I gave this a shot and pinned it according to pre-disassembly photos. I must have nailed it because the end snapped off right at the pin hole. (There's that work hardening, I guess)
It seems improved, but still a little tight to the outside of the regulator.
There is another issue at hand.
One of the lever pins is landing on the impulse face of the escape wheel teeth. The other pin is landing on the locking face nicely, but is losing much of its impulse due to EW pivot slop as shown in the first video of post #15 .
The most obvious ways I can see to solve this would be to either set the beat to favor the incorrect pin (tried it, did not bear good results), or try to nudge the pin a bit south so that it engages the locking face. I highly doubt that this is the recommended solution.

-Jeff
 

RJSoftware

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The pins should be perpendicular. Don't bend. Sounds like slop from worn escape wheel bushing.

One of the best test for pivot/bushing wear, is to let down main spring power. Grab main spring wheel make small twist back and forth. What this does is allows you to see pivot/bushing wear in the whole gear trane.

Pivots eat bushing holes eventually causing an oval shape as they eat in the direction to escape pressure. Jiggling the main wheel back and forth makes pivot tips jiggle side to side, showing how much slop exist.

The general rule is 1/3rd of pivot diameter or greater is too much slop.
It's just a guideline.

When gears mesh (gear to pinion), they slide across surfaces. To slide they must not be fully engaged. Otherwise at 100% engagement there is power robbing friction. The ideal engagement (depth) is 90%. You should be able to see daylight between a gear mesh under magnification. Bushing/pivot wear causes tight mesh.

The ideal tool to posses is a depthing tool. But, not often needed by clock repairing. In fact I believe the majority of clock repair people dont own one. Basically you take 2 gears at a time, insert into tool, adjust the depth, roll gears with fingers till it feels right. The tool then has scribes to then transfer that distance to plate. A form of triangulation using sweeping arches.

But in the common everyday repair, examining the existing bushing hole has enough remnant of the original factory hole to accurately locate the original position. Unless it was bushed poorly before.

So it is important, when you repair bushing/pivot location to first establish a precise X marks the spot. I use a razor knife, the kind like a pencil, to make a slight scratch under loupe magnification. I hate using marker or pencil, tape, etc. as my fingers tend to accidentally rub off mark. The razor is thin so the slight scratch is accurate. I free hand the scratch as using straight edge can often offset. If I miss, I rescratch making the correct one more prominent.

Consider the issue of how critical depthing is. The measures are soo small that they almost seem imaginary. Can you see light between 2 gears held in front of bright light? No, well then your mesh is too deep, start over. Btw, too loose is frictional too.

On smaller clocks, like yours, and watches, you have one advantage over the larger clocks, and that is the ratio of pivot and plate thickness. On larger clocks the pivots are fatter and plates thinner (ratio wise).

On larger clocks typically would employ KWM bushing install and fine tuned by broaching after dressing pivots.

Pivots should always be dressed before broaching (You cant make a pivot fatter). That is also why I purchase bushings with smallest hole available.

But, for your escape wheel slop you can do something entirely different.

After doing the X, to the best of your ability.
After dressing the problem escape pivot, filed if needed, burnished.
Mic out the dressed ew pivot and find compatible drill bit or pivot wire.

Then with a round nose punch, with tip approximately size of a bb (bb gun), you can grind any punch to conform. Peen the hole dead center so it slightly closes.

Many many times, you can just poke through with original pivot and the results will be fine, but be careful.

The drill bit, broach, pivot wire are just options to re-open hole. What you are doing is sacrificing a tiny fraction of bushing thickess for more snug fit. The ideal snug fit has about 3 to 5 degrees slop, so if you stand gear in bushing hole, the gear should only lean 5degrees. Using an identical sized pivot wire or plug gauges is a better approach than a tapered broach. But pivot wire is cheaper than a plug guage set.

The big taboo on peening bushings is mostly from larger clock butchering. This is where some would take a punch to surrounding area of the bushing hole and basically kneed the area towards the hole.
 
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JeffG

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Thank you!
I'm reasonably comfortable with installing bushings, though the smallest I've worked with thus far has been about .9~1mm. If I remember correctly this EW pivot is .6mm. That's probably like a telephone pole to the watch guys, but it's new territory for me. I like the idea of using a punch it as it would negate the run out in my bushing tool, but again, new territory. I have not plug gauged the hole to check for roundness. Do I need to make the hole round around the original center before peening it? Also, the amount of movement I'm seeing is more than 1/3 of pivot diameter. Would peening it closed be effective without doing damage?
I'll try to get a close-up video later today.

p.s.- the pins on the lever are not perpendicular, but are symmetrical. I wonder if the heat from repairing a small crack(post #15) was enough to change the geometry between the balance and the pins.

-Jeff
 

R. Croswell

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I gave this a shot and pinned it according to pre-disassembly photos. I must have nailed it because the end snapped off right at the pin hole. (There's that work hardening, I guess)
It seems improved, but still a little tight to the outside of the regulator.....
Are you saying that the hairspring actually broke off at the point where it is pinned? If the hairspring is now shorter you will need to readjust the beat for it to run, but it may run faster that can be compensated for by the rate adjuster.

RC
 

JeffG

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Are you saying that the hairspring actually broke off at the point where it is pinned?

RC
Yes. It broke off right where it is pinched by the pin in the slot. The spring formerly stood about 3/32" proud of that point. Now I will have to pin it with no extra spring sticking through the hole, and accept that it may run a little fast.
-Jeff
 

RJSoftware

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The punch is done on outside face of plate, oil sink side. Sometimes you can loosen up plate screws/pins just enough to remove the specific gear.

You can cut/grind off one claw of a disposable hammer head. Insert hammer head in bench vice so that the one hammer claw acts like a shelf/anvil. You can then rest inside surface of bushing so to peen. The hammer claw can reach in movement while assembled minus the gear you're working on. The trick is really for more complex movement. It can save you time from disassembling and reassembling.
 
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shutterbug

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You could probably use a heat sink of some sort and solder a short piece onto the end of your spring to get the length you need for regulation.
 

JeffG

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You could probably use a heat sink of some sort and solder a short piece onto the end of your spring to get the length you need for regulation.
Oh wow!
That delicate work sounds well beyond my soldering skills!
I'm reasonably sure that only the excess length broke off. Time will tell (ha!) if I can get this balance swinging better.
Currently working to tease the end out a little because the coil was being pulled off center by my previous molestation (post #32).
-Jeff
 

JeffG

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I am declaring my hairspring manipulation a success!
Still a touch off-center, but moving within the regulator and threading through the termination slot without assistance.
The clock is almost up to 270˙ of rotation. A slight nudge on the great wheel spins it up to 360˙, so until I address the EW and lever bushings, I don't think I will find further improvement.
I have put it all together to see how it runs.

IMG_9399.jpg

If I was to sell it, I could probably recoup some of my time at $2,245.83.
Continuing to learn and receiving so much help and guidance is priceless.
Thank you all!

p.s.- it's starting out slow! Woohoo!

-Jeff
 
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nawccmatt

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This thread was super helpful! I've been working on a Sessions clock with a very similar movement to the one shown here and using these tips was able to get it working again (after replacing the mainspring).

2022-05-13 007.JPG
 
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