Amplitude numbers

[nickpeh]

Hi, 

may i know what's the main factor causing the amplitude numbers on time grapher to lower or went up over 200? Sometimes when regulate to a certain point, amplitude will rise and beat error will shift, checked but no clues, shed some lights? 

[jdm]

Amplitude is the combination of the efficiency of the mainspring, train, balance and hairspring efficiency. One imperfect element will make it decrease, a combination of defects will make it decrease even more.

Which movement are you working on?

 

[nickpeh]

orient 46941

[nickpeh]

when mount watch on time grapher, all except the seconds loss/gain per day showed dash. I tried moving the shorter arm ( hairspring mount stud lever) clockwise and counter clock to see if there's a reading but nil avail. 

[JohnR725]

To be nice to have a picture of the timegrapher as sometimes pictures will show thing is that your description does not. Then it depends upon the timing machine but usually if it can't pick up what it perceives be a valid signal it will display dashes or no numbers or no display giving you a clue that it's having a problem. Then this wouldn't be the same watch described in this link would it?

http://www.watchrepairtalk.com/topic/5657-orient-46941-regulating/

[nickpeh]

Yeah, but i tried several methods fto om cleaning to hairspring replaced with adjustment, cant get it right!  I took that as learning phase, will tackle next movement after this , next is st6 from a replica datejust. Sometimes the loss gain show plus sign , at time minus, am i right to say if show dash means loss?

[rogart63]

27 minutes ago, nickpeh said:

Yeah, but i tried several methods fto om cleaning to hairspring replaced with adjustment, cant get it right!  I took that as learning phase, will tackle next movement after this , next is st6 from a replica datejust. Sometimes the loss gain show plus sign , at time minus, am i right to say if show dash means loss?

Doesn't look like right? Not sure what it is? But you don't have a very high amplitud? And by the look of it? A very strange curve on the timegrapher? 

Have you cleaned the pallet fork? 

The beat error is alright as far as i can see? There should be a thread in here at the forum about timegrapher readings? Somewhere? 

[JohnR725]

Simplistic answer if the amplitude is right then everything else flies out the window until you get the amplitude at least 200°. This is where having a timing machine and/or software that would let you look at a oscilloscope display is sometimes useful to look at the waveform. So simplistically you have a major problem the timing machine is telling you that and you have to fix that before you can put it back on timing machine it's not a regulation issue.

So it would be helpful for background on the watch? So I assume it's the one at the link that you had hairspring issues with. Hopefully when you changed the hairspring you got a balance completes because you can't swap hairsprings.So other link you did a partial disassembly did you clean the rest of the watch lubricate etc.? We can make all kinds of wild guesses but we need to know what the condition of the entire watch.

Note the beat is not correct look at the graphical display it is not 0.4 those lines are really far apart. I've seen on the Chinese machine they can actually go over the 9.9 so conceivably you are grossly out of beat but with amplitude that low everything gets magnified anyway so worry about the amplitude first.

 

[nickpeh]

John thx for point out, 

I didn't overhauled the entire watch, just parts removed and replaced were cleaned, watch bought over from ebay and lying around until I decide to use it , found not keeping to time, decide to open up for a check. I thought it was the hairspring issues and indeed after removing saw kinked, I replaced hairspring together with balance, but hairspring was reassemble to align with the pallet fork when mount onto balance cock.

Now since u said not running right , probably need time to remove all parts and check one by one. I am not experienced in overhauling, will update if I manage to or else just leave to the professional. 

[Ado213]

Hairsprings clashing, try your reading in PD 

[rodabod]

Maybe take some more photos of the balance and hairspring while it is resting. 

[nickpeh]

so u suspect hairspring, I did several adjustment on that..I can get near to perpendicular between them but not 100%. will that actually affect? I dont have microscope to snapshot a close up..

[rodabod]

There are so many questions we could ask which would be answered by one photo. See the attached photo of a phone microscope. They cost around £1. 

If you think the hairspring looks ok, then I would check that the impulse jewel on the balance is sitting approximately between the banking pins when it is resting*. 

*It will actually be slightly to one side of the the centre if the pallets (lever) are hugging the banking pins which will happen if there is any main spring tension. 

[rodabod]

[nickpeh]

5 hours ago, rodabod said:

 

Thank u for the input, I am aware of the  roller jewel position. I didn't managed to peep in there, am I right to say if the balance assembly with balance cock mounted on, if roller jewel in the right position, it should swing to and fro freely when given a slight push? This is of course without the mainspring winded.  I read somewhere in other forum, someone said that japanese movt usually have low amplitude, is it true? 

[rodabod]

Japanese (well, Seiko) tend to have lower amplitude. 

You are correct to say that if the impulse jewel is in the right position then then it should swing to-and-fro easily. In fact, it will automatically start swinging if it is set up correctly - that's part of the Swiss lever design. 

[JohnR725]

So watch companies publish all sorts of interesting specifications for watches. We can freeload off of other companies to get an idea of what we should be looking at. So some companies will specify the freshly serviced watch fully wound up should have an amplitude between various degrees. Omega publishes what the watch should be doing at the end of 24 hours. After all you want the watch to be able to run at least one day. They do care about timing specifications fully wound up and And at the end of 24 hours but They only care about amplitude being a certain minimum at 24 hours.

So as I have the specifications looking through the very lowest acceptable amplitude is 160°. The numbers vary with the various watches.So the most common at the end of 24 hours is 200° the difference is based on the running time of the watch. Modern watches can run at least 48 hours they're going to have a higher amplitude at the end. So the watches at 160° tend to be watches it have much shorter running times like in the 30 hour range. So anything modern should be better than this and it still has to keep time within their specifications.

So you're 160° as a guess is not at the end of 24 hours it's probably fully wound up?

So basically amplitude is an efficiency test. Other ways to test the balance wheel without power on the watch supply energy to the balance wheel the started to rotate and it should oscillate back-and-forth over quite a few seconds before it comes to a stop. Then a lot of times we turn it upside down because sometimes the problem only occurs in one position. But basically the balance wheel has to have very little friction or you're going to have timing and running problems.

So problems for newbies with watch repair is there's a lot of places where you can have problems that you're not going to recognize. They hairspring has to be absolutely flat and not touch anything other than at each end and where the regulator pins are.Depending upon the watch a lot of times this is a really hard to see even by us seasons people that know what were looking for. So simplistically a lot of places for newbies to have problems. Then we rely upon your description to help you diagnose as a newbie you can't necessarily give us what we need which is why we need a photograph.

[Ado213]

8 hours ago, rodabod said:

Japanese (well, Seiko) tend to have lower amplitude. 

You are correct to say that if the impulse jewel is in the right position then then it should swing to-and-fro easily. In fact, it will automatically start swinging if it is set up correctly - that's part of the Swiss lever design. 

Agree, japs have lower amplitude which isn't always deregoritery as poise doesent theroctically exists under 220 deg. But I suggest 190'is well under a positional rate

beat error can self start a watch at 9.9m/secs if the escapement is wrong

[nickpeh]

I removed hairspring to inspect again , took some pics ..

 

[rodabod]

Can you photograph the spring when it is fitted in the balance cock and within the index pins (regulator pins)? The collet should line up with the jewel hole. 

[nickpeh]

hairspring with balance assembled to balance cock

 

 

[nickpeh]

Even i get beat error closed, still loss and gain far from target, whenever regulating lever moved the beat error shifted and mostly on high loss side..

[nickpeh]

[rodabod]

Are you sure that the beat rate is 21600? Can you check since I don't recognise the movement. 

[rodabod]

On 26 February 2017 at 5:35 AM, nickpeh said:

orient 46941

I missed this earlier. Ok, so it is 21600bph. 

Assuming that the balance looks like it is actually swinging around 180 degrees, then my first guesses would be:

The index pins are not contacting the hairspring (but it looks like you managed to adjust the rate, so maybe it's ok

The balance wheel is wrong (too heavy).

The hairspring is wrong.

I would still check that the balance impulse jewel is centred between the banking pins like I suggested. Just use an eye glass and lots of light. When I look at your photo of the balance, I would assume the impulse jewel sits between two of the three balance arms.......