Accuracy?

[pugwash]

What tools do you guys use to measure the variance? Is it an online atomic clock? Any other software that helps?

I use my Mac, synchronised to a time server, or I use a digital watch.

 

[drachen]

I am using http://www.time.gov, the official federal government time site.

This is typically accurate to less than .3 seconds in a browser, occasionally around .9 seconds off. It self-sychronizes by measuring the time for a network round-trip between the time server and your browser and interpolates the difference.

I am down to around 12 seconds per 24 hrs at this point (interpolating based on 8 hrs since I last calibrated and am only 4 seconds off), and will let it go for a while.

Now the question is what will happen over time.

Yes, I am wearing it. Not much point in a rep unless you are going to wear it. Yes, I would probably tear my hair out if I had spent S5K on a gen and then accidentally scrape it across my kitchen granite countertop... !!

The point of a rep (for me) is to be able to wear it daily and not feel bad if I accidentally damage it.

 

[gaspot]

I just turned the regulation screw a few notches anti-clockwise on my ETA 2836-2. It seems to have sped-up instead of slowing down.. Did I do something wrong?

 

[MartyUtah]

This is a great thread. I'm a complete noob who's taken advantage of my first cheapo PAM rep (exactreplicas, before I got schooled) to open it up and dive into regulating the hairspring. The Seagull ST-25 was running two minutes a day slow, so I cracked that sucker open like an oyster using some vicegrips (the duct tape thing wasn't working for me). The vicegrips I wouldn't recommend since I scratched up the caseback, but that's what the cheapo rep is for.

I managed to sync the small seconds on the rep PAM using the hack function to the digital readout on a radio controlled Seiko, had a brew to steady the nerves and started moving the regulating arm away from "lever 35" with a tiny screwdriver . I felt like I was defusing a nuke, but it's a thrill to see the accuracy improve. With just two adjustments I've got it so the movement is running only 10 seconds fast a day. Quitting while I'm ahead.

Thanks guys for all the advice, now it's back to the poormanswatch website to buy their caseback opener, since I won't be so stupid as to use vicegrips to the caseback of my expected Trusty rep. I recommend some relaxing music and a Polygamy Porter ale to steady the hand when poking a micro screwdriver into your jewel like movement, but boy, it's fun.

 

[fakemaster]

Accuracy hehe.

 

[swissaddict]

In my relatively limited experience, Swiss ETA-powered reps have had the best accuracy out of the box at around +10 to +13 seconds per day. Asian 7750's have given me around +18 to +24 seconds/day. Only had two Asian 21J's so far and one ran about -40 seconds/day, the other was almost a minute fast per day. Just my experiences, for what it's worth.