strange timegrapher results

[Crockpot]

Hello everyone. I’ve recently serviced this Elgin grade 347 and it runs well but after a few minutes the rate jumps up to a few minutes fast per day for a few seconds and then back down to 0 seconds per day runs fine for awhile and every now and then sporadically jumps up again. Hairspring sits between regulator pins not hitting anywhere and all seems fine. In 24 hours it’s usually 30 seconds fast per day. I think it does worse right after winding.any help is appreciated.

[Nucejoe]

How far apart is " sporatic"    perhaps your observation on TG hadn't been long enough to see a period of occurance. 

I make a habbit of checking how the movement runs on TG before and after  installing the dial and hands. 

Regs 

[Crockpot]

It was the regulator pins. They were too short. Making the hairspring slip out from between them and pop back in place hence the weird results. I luckily had a spare regulator that worked perfectly in this movement. 

[Nucejoe]

Great,

Pretty movement 

[Crockpot]

Thanks, Nucejoe. I rechecked the movement on timegrapher and realized that every 5 minutes it was still jumping minutes fast per day. So I decided to take a better look at the train and found some slightly damaged teeth on third wheel and fourth wheel pinion where they meet. I counted teeth and pinion and luckily had spare parts so I went ahead and changed all train wheels except for center wheel and now the watch is staying running steady and strong. This time I left it on timegrapher for 20 minutes and no problems.amplitude also improved some. I figured this information may help someone else with this.

[Nibbler]

Great looking movement.

[JohnR725]

On 2/20/2022 at 10:45 AM, Crockpot said:

runs well but after a few minutes the rate jumps up to a few minutes fast per day for a few seconds and then back down to 0 seconds per day runs fine for awhile and every now and then sporadically jumps up again. Hairspring sits between regulator pins not hitting anywhere and all seems fine. In 24 hours it’s usually 30 seconds fast per day. I think it does worse right after winding.

Even though you fixed all your problems I'm still going to comment a few things. So initially you're describing something that looks exactly like Rebanking. I have a link to a video which explains basically of too much energy when the watches fully wound up. This can sometimes happen with variety reasons or if the mainspring is too strong which can happen on American pocket watches because we don't have the choice of mainsprings that we once had. Typically today one size fits all but one time you would had several different strengths for your pocket watch.

https://youtu.be/Rcqrb3_vin8

On 2/20/2022 at 12:30 PM, Crockpot said:

It was the regulator pins. They were too short. Making the hairspring slip out from between them and pop back in place hence the weird results.

There's nothing that says that you can't move the stud up a little so that the hairspring stays between the regulator pins.

On 2/20/2022 at 11:44 AM, Nucejoe said:

I make a habbit of checking how the movement runs on TG before and after  installing the dial and hands. 

I always thought this was standard watch repair practice? In other words once the watches running you verify it's running on the timing machine without the dial and hands. But typically on this group and other places the enthusiastic repair person will case up the watch and only then put on a timing machine and discover perhaps there's a problem.

1 hour ago, Crockpot said:

I rechecked the movement on timegrapher and realized that every 5 minutes it was still jumping minutes fast per day.

This is where either a different timing machine which is very expensive or the old days of the paper tape machine was better. Because of the paper tape machine you can run enough paper tape to try to find a pattern. It's harder to find patterns on a liquid crystal screen when you of a limited amount of time. But you do watch the numbers go up and down and see if you can find a pattern.

1 hour ago, Crockpot said:

changed all train wheels except for center wheel and now the watch is staying running steady and strong.

I assume you change the escape wheel? Even though it has a happy ending did you notice the pocket watches serial numbers on all the plates? Typically the watches were made in batches the plates roll made for each watch. You can swap a lot of components on a pocket watch but you want to be careful about swapping everything. Especially when you get close to the escapement because each escapement was adjusted for each watch. As the pocket watches no manufacturing progressed the ability to make things to tighter tolerances it becomes less of problem. But an earlier watches swapping all the parts out can be an issue. So just a warning for the future you have to be careful when you do this because sometimes the parts are really exactly the same.

Then the timing machine? The microphone rotates you can look at the watch in different positions. Sometimes is nice for diagnostics like dial-up and dial down should basically be identical. Typically with a pocket watch you like to check it crown up as that's a position that the watch might be and if somebody was carrying it.

Then I don't know if you're familiar with the site at the next link? Is looking at your movements and something caught my eye? Notice the ratchet and the crown will both have decorations? They usually don't do that on all of their watches which is why I took the trouble to look up the serial number. You'll notice they made the watch which was typical of the day in batches of 1000 and they made 20,000 of these which is a relatively small run. Also they time the watch and three positions so you can at least rotate your microphone and see what it does in other positions. Basically they're saying this is a little nicer grade watch your standard 17 jewel Elgin watch

https://pocketwatchdatabase.com/search/result/elgin/19093454

 

[Crockpot]

Thanks John I really appreciate you taking the time to explain all that. I just put the original escape wheel back in.and I’m not going to wind fully anymore to try and help with the Rebanking. Good day sir.

[Crockpot]

Well today I measured the mainspring and I’m looking on eBay for a mainspring that’s a little less strong and I can’t figure out how to order the correct one. My mainspring measurements are 2mm tall by 0.15mm thick by 20 inch long. Can someone please help me figure out which one I need? Thanks

[JohnR725]

7 hours ago, Crockpot said:

My mainspring measurements are 2mm tall by 0.15mm thick by 20 inch long.

First step you've already done which is measuring the old spring

Then typically I would go right to one of the mainspring list I used for ordering the mainsprings but because you're new to all this I'm going to expand upon that considerably.

Then typical with American pocket watches getting a spring isn't always a straightforward process.  some of the manufacturers will give you a part number and their variations a need to know which thickness you need. Or it could be other variations.

One of the nice things about the pocket watch database especially with Elgin is parts listings. Notice on the left-hand side the reference to parts then you go to Springs and I snipped out the image for you. And noticed two separate numbers and one of the Springs gives you the thickness in inches which will need a little bit.

Than the Elgin parts catalog 1915. I snipped out the image of what the various ends look like. If you have an early enough Elgin but typically this will be a key wind watch you couldn't have separate Types of ends as they actually change their barrels in the middle of production and you can have either or and the old style is no longer available at all.

From the third image we narrow things down really fast. We knew from the image of end styles that they're both the same then you go up to lists to see why there was a difference. It depended upon the type of mainspring barrel you have. The width as you call it how tall it is is supposed to be 2.05 mm but 2 mm is close enough. Then on the pocket watch database is supposed to be a strength of 0.0075 inches so now we know which spring you're supposed to have perhaps? Yes you thought it was that simple.

If you have a watch that has too much energy because the spring is too strong Elgin at the factory used to solve the problem by swapping mainspring barrels. When the watch reached quality control or at some point in time there looking at how much amplitude the balance had if it had too much you would go back to the spring department where they would swap for different mainspring barrel that had less energy. If it hadn't lack of amplitude it would go back to the escapement adjusting department. Which becomes a problem for us because we can't do that and you also go the next page the catalog represents the other problem back she had weaker springs. Although for your watch even though they had extralight spring is it looks like your spring is still as light as it came. But I'm still do a show you the image.

Then I'm attaching a PDF which is what I usually look at when I'm ordering mainspring is because it seems that corresponds most closely to what is available brand-new. This is where there are no extralight Springs number choices shrink considerably but typically for purchasing new spring is these are usually available.

Then to help you out with the confusion of what is it Dennison I'm attaching the  cross reference chart. American pocket watch mainsprings use the following measurements possibly all of the same time inches, metric and Dennison. A lot of times the packages will be marked with variations of those to do have to know which numbers you're looking at and how confused you want to be

7 hours ago, Crockpot said:

I’m looking on eBay for a mainspring that’s a little less strong

Looking at the  PDF mainspring listing we see that the 2339 came in three separate strengths.

Then how did you measure the strength or the thickness of the mainspring? Typically veneer calipers may be off by a little bit a micrometer is usually the best.

It's now brings up an interesting problem here mainspring if you measured correctly as weaker than any of the other mainsprings available? So basically want to go for the thinnest spring you can find I usually prefer to get original springs even from Elgin a lot of the original springs are still in really good condition really catch is because their steel they can't rust. It's really important to never hold a steel mainspring with your bare hands. Elgin once had a really nice multipage hand out on why mainsprings break and that's because people hold them in their hands and the fingerprints you leave behind and cause rusting or micro fractures and that's why the mainsprings will shatter. Usually will shatter into whole bunch of little pieces but that's not just unique to old mainsprings I've seen it happen to newer springs for a variety of reasons

Now the question that you have what does your picture mean? You looked up mainsprings by looking for 12 size Elgin didn't you? But if you look at the Elgin catalog or even the security PDF notice there's a lot of different 12 size mainsprings. Then those numbers where we seen those numbers before? They look like Dennis and numbers.

Looking at the security PDF looks like were looking and Dennison for 12 – 6– 20.

I think a better way to do this would be go to back the eBay search for Elgin 2339 he don't even need to specify it's a mainspring. Then you get a listing sin brings up another problem? Another problem is there's a new number that indicates it is for the watch in fact the listing is like this Elgin Factory DuraPower Mainspring for 12s No. 6093 / 2339 - Alloy. That's because Elgin had in addition to steel spring as they had their own alloy Springs which should be a better spring but it is a different part numbers that requires snipping out a different book image to show you wanted us.

So now you should have all the information you need to go back to eBay do a different search and see if You can find a mainspring.

 

 

Mainspring - DennisonChart.pdf Mainsprings security American pocket watch.PDF

[Crockpot]

Thanks a lot man. I never understood all those charts until you explained it to me like that. I ended up finding my better set of calipers to recheck my measurements and somehow the calipers that I used yesterday were off. Measurements were actually 2.05mm by .19mm by 20 inches. So I ended having a choice between a dura power mainspring .0073 thick.#6093 & Elgin steel mainspring . 00725 thick.#2339 so I went with Elgin that’s a tad smaller. But thanks again for the charts they were a lifesaver. Have a good day.

[JohnR725]

Yes measuring mainsprings calipers can be or have issues with the thickness. It's hard to hold the thing absolutely parallel to the jaws you end up getting wrong measurements. The length you don't have to measure exactly just need the grasp what it corresponds to. The web use it helps if you measure the center part of the spring we have several coils.

Then unfortunately with pocket watch data it seems to be the best place to find it is on eBay. Which is largely where the stuff I have came from. One of the reasons it may not be available out in the wild is that some of the files are really really big greater than tens of megabytes. So while you can download all kinds of stuff including some pocket watch material if you know where to look usually eBay is the best place to buy a disk with a whole bunch a technical stuff.