Movement Accuracy Question

[mlfloyd]

I purchased a Steinhart Ocean 1 Green last month and it uses a 2824-2 movement. After setting and synchronizing the time to the second, I checked it 24 hours later and it was spot on. 24 hours after it was 5 seconds fast. 24 hours after that it was 10 seconds fast and each 24 hour cycle after it increased by 5 seconds.

 

Does this mean that the movement is accurate to +5 seconds a day?

 

My thought when I would hear this statement concerning movement accuracy was that time would consistently be 5 seconds fast and increments of 5 seconds as each day goes by.

 

Can someone explain how movement accuracy is to be understood?

 

Thanks.

 

-Mark

 

 

Sent from my iPhone using Tapatalk

[ceejay]

Movement accuracy is largely dependant on 2 factors. Position & environmental conditions. This is after you have taken mechanical inaccuracies out of the equation.

 

The goal is to have the least amount of variance in time keeping, no matter what orientation the watch is in or whether it's freezing cold or piping hot.

 

I will write up a more detailed explanation when I have time. If your watch (whilst being worn) is at + 5 seconds per day, then it is fairly accurate.

[mlfloyd]

I found that giving it about 20 winds twice a day will maintain the accuracy to about 3-5 seconds a day while wearing.

[automatico]

"I found that giving it about 20 winds twice a day will maintain the accuracy to about 3-5 seconds a day while wearing."

 

In my experience...Eta 28xx automatics do not take kindly to hand winding other than 20 or 25 turns to get a movement going.  They have a somewhat fragile autowind assembly (finicky reversers) and the crown wheel post made on the movement plate can wear rapidly if not lubricated properly because of the added friction of the autowind assembly when hand winding.  When the reversers get dry or dirty, hand winding friction markedly increases causing more wear on winding parts.  The 2801 series manual wind movements have no autowind parts so this reduces friction and wear when hand winding.

 

I have worn a lot of Eta 28xx automatics and most will keep time within 10 or 12 sec/day when worn, many may be better.  If they are laid down or put on a winder the rate may change.  Most tend to become a bit erratic when not worn enough to keep them wound up or when getting close to running down.

 

Imho...

Quartz watches, accuracy claims, and screw down crowns have spoiled today's mech watch wearers (including me).

Quartz watches because they are accurate, rugged, and basically trouble free.

Accuracy claims by 'COSC' etc. tested watches.

Screw down crowns because they make time correction more of a hassle.   

 

Trivia...

In the old days Hamilton Watch Company used to brag about their RR Approved watches having 'Railroad Accuracy'.

What was 'Railroad Accuracy'?

Officially it was plus or minus 15 seconds a day...with a catch.

The catch...All crew member watches had to be within 15 seconds of each other and within 15 seconds of the 'Official Time' when checked against the 'Chief Train Dispatcher's Official Time' when going on duty.

Who must have a 'RR Approved' watch?  All Transportation Department company officials, all train crew members, all dispatchers, all station agents, all Trainmasters/Road Foremen, and anyone in track maintenance management positions and/or anyone that worked where trains were running or were affected by train movements.

Division Superintendent = the person in charge of a certain RR Division.

Assistant Division Superintendent = assistant to the Div Supt (usually more than one).

Division Engineer = the top official over the T&S of a division.  T&S = all track and structures (all tracks, company land, and buildings).  'T&S' could also mean 'Track and Surface' if you were in the track/surface department etc.  'Surface' = land close to where the track was including the 'ballast' (rock). crossties, tie plates, spikes switches etc.

Master Mechanic = the official over rolling stock, but not locomotives.

Chief Electrician = over diesel/electric locomotives.

Chief Dispatcher = the Train Dispatcher in charge of all train movements on their division.  It was usually also an Assistant Division Superintendent position.

Trainmaster = an official in charge of train crews on the division.  Usually the division was split up with different Trainmasters being in charge of certain parts of it.

Road Foreman = an official in charge of locomotive engineers and engineer trainees.  They also had authority over other crew members, but mainly engineers and trainees.

Trainmasters and Road Foremen were on duty 24/7 and had company cars and expense accounts.  Many burned out, a few had to be 'reprogrammed' and some were 'retired' early for 'stress related issues'.

Then there was the Mechanical Department over locomotives and rolling stock and the Signal Department over stationary train signals, electric switches etc.

Etc, etc.

 

[Nanuq]

[mlfloyd]

I’ll give it a try.

 Thanks Nanuq.