Hi all,
I'm wondering if people here have timing machines at home? How much do they cost? any recommendations? Do the timing machines also measure amplitidue?
ta
daniel

calling Archer!

 

In particular, I've seen this on the bay for less than $200: http://www.ebay.com.au/itm/New-Mech...26?pt=LH_DefaultDomain_15&hash=item35b9c3caf6Purchases made through these links may earn this site a commission from the eBay Partner Network

 

I've got one, came from Ace Timer in the US. Check eBay for their prices or their site.

http://www.acetimer.com/Timing-Machine/

It does a fairly good job for a watch tinkerer like me and as long as you know the lift angle you can get nice accurate results.

 

same machine! good to know.

 

We did this once in another thread when someone bought a timing machine. I'll just caution you that having a machine like this and checking your watches with it may lead to more questions, concerns, and frustrations than just not knowing. Now is your chance to take the blue pill...

The machines linked to are inexpensive (read cheap) Chinese made machines. They do the job, but are not something any professional I know would use on a daily basis. I have one as a back-up in case my Witschi goes down, but it has several drawbacks, and these may apply to the machines in the links in this thread also:

1 - Flimsy - on mine where you plug the microphone stand in, the board it plugs into is not supported well in the case of the machine - plugging in the cord or moving the stand around too much could cause damage to the board.

2 - Features - the features of these machines are very basic - they won't do a lot of things that a newer professional grade machine can, but they will tell you something about the watch for sure. To get accurate balance amplitude readings you need to know the lift angle of each movement you check.

3 - Sensitivity - these machines tend to need a quiet room to get good readings, as they can pick up stray noises from the surrounding area. This is particularly important on the very base model machines where the gain can't be adjusted for the microphone stand. A professional machine is not really affected by most noises in the room.

4 - Accuracy - the quality of the quartz crystal used in these machines is marginal compared to a professional level machine. In a high end machine the crystal is aged and stable when it's put into the machine, and these cheaper machines can drift quite a lot. Probably not terribly significant for a hobbyist/collector, but when people are paying you for accuracy it's important.

I'm all for people learning more about the technical side of watches, but depending on your personality type, this might not be a good purchase. It's like people who but a brand new watch and then look at the hands and dial with a 20X loupe - you will find things you don't like.

I can basically predict with certainty that you will put a watch on this machine that you think is running well, and it isn't. Some people would welcome that, and some would not.

Hope this helps.

Cheers, Al

 

Especially if, because it's a cheap machine, you really don't know if it's the timer or your precious watch which is wrong

 

While in with a watchmaker in HK, I said, shall I get one?
his reply was it would cost me a fortune.
why I asked, is it expensive?
No, he replied, you will think most of your watches will need servicing - and that I would not be able to interpret it.

i bought one anyway.

 

You're as crazy as I am ;-) Why not: It's only paper!

 

In many ways this is a continuation of the 'when should I get my watch servied' thread recently. Al convinced me that just asking my watchmaker to look at some of the cap jewels was insufficient, so I also looked at power reserve and juding timing accuracy against my tablet's stopwatch. Then the issue of amplitude was raised....

What is 'lift angle'?

 

Got one some time back. It can not be read as some would read holy scriptures, but it gives a decent indication if the movement is ok or way out.
I always check my new purchases when they arrive, and then decide if i will send the watch to my watchmaker for a more thorough assessment.
Warmly recommend it for the technically oriented!

 

and I guess that is exactly what I'm planning

 

The total lift angle is the number of degrees where the impulse pin (roller jewel) is in contact with the pallet fork. The balance amplitude of the watch displayed on a timing machine is a calculated value based on some sound measurements the machine takes, and the lift angle.

If you have the lift angle incorrect on the machine the amplitude readings will be incorrect. The rule of thumb is that for every 1 degree error in lift angle, the balance amplitude will be in error by about 6 degrees. This can be important when determining if a movement meets the minimum balance amplitude requirements set out by the brands.

Lift angles can vary from 36 degrees on the lower end, to 56 degrees on the upper - off the top of my head I think that is the lowest and highest I recall.

In the modern Omega world, the Cal. 2500 co-axial escapement watches are 38 degrees lift angle, and the Cal. 1120 are 51 degrees - same base movement in the ETA 2892....

Cheers, Al

 

I started with one of the cheap Chinese ones. It was fun to play around with and ultimately was the impetus for a whole new phase of research and learning. Additional knowledge can indeed be quite costly, as I decided to send some complicated pieces off for servicing after noting their poor performance.

When I'd sell a watch, I found myself including timing details or a quick snapshot of the time grapher to counter the healthy buyer skepticism whenever a seller says, "recently serviced." The more I did that, the more I realized I needed to have confidence in the results that I was essentially warranting. So I upgraded to a Witschi Watch Expert II at 15x the price.

I sold the Chinese one, but before boxing it up, I compared the Chinese and recently calibrated Witschi results. The Chinese one was surprisingly accurate... like within a few seconds per day.

As Al says, they are extremely finicky to get good results. The room has to be absolutely silent and you can't even let your shirt sleeve graze the countertop while the mic is on. They are also more likely to report "out of range" at the extremes, where the Witschi will still give a reading.
For someone debating the purchase, I'd say go for it. AceTimer sold me mine, and I have no complaints. Do take care to check the electrical plug and voltage/frequency rating of the unit depending on where you're located.

If you do pick one up and want to learn how to interpret different timing results, pick up a vintage copy of "Better Watch Repairing Faster" by Lewis and Lee. It's written for the old Watch Master machines, but the content is still relevant. They go through all of the mechanical basics that can effect the timing, then they spend 250 pages showing specific results on the Watch Master and explaining the fault, whether it's a dirty jewel or a poising error or a rough overcoil. You won't sit down and read it. But when you put your watch on and it's wonky, it's pretty cool to have it as a reference to figure out what's going on. Copies are hard to find, but keep checking ebay and Amazon and eventually a copy will show up.

 

Again, echoing Al, it's important to make sure you have the right lift angle set on the machine to correspond with the movement that you're timing.

The Alliance Horlogere website, here has a good database of many of these lift angles. If what you want isn't on there, send me a PM. I've got a PDF with some of the missing ones and can send it to you.

 

A fine example of watch masochism

 

Just to clarify, this procedure is used primarily when you have a watch with an unknown lift angle, and is not typically done on every watch you check. While there are circumstances where the lift angle can change on a watch, these are rare, at least on modern watches.

Most manufacturers publish a list of lift angles for their movements.

Cheers, Al

 

Quadrophenic-Schizophrenia

Great clip, Jim
Thanks!

 

Thanks Al,
Where would one find this information for older Omega movements ?

 

I've got some old Omega lift angle tables somewhere, I'll dig them up.

It's an Excel spreadsheet compiled by John Davis (2-10-08, 7-14-03, 12-14-08) from materials supplied by Vibrograph and Witschi as well as a list compiled by Hal Herman, April 1993.

Can I attach a spreadsheet to this thread or do I need to email it?