Equation of Time (RGM)

"22 Standard"

A Homage to Hamilton's classic deck watch

by Matt V.

January 2005

The successful revival of a timeless classic...


Founded in Lancaster, Pennsylvania, in 1892, Hamilton has been producing watches for the general public since 1893. But in 1940,  the Hamilton watch factory focused production on timepieces for the US military and supporting the war efforts. Over one million different watches were produced in their factory during the war and Hamilton continued to develop and produce new timepieces in Pennsylvania for as long as 1969. Ever since, the Hamilton Watch Factory is part of the Swatch Group and over the past few years has released a number of homage watches celebrating some of their past horological successes. But let's go back to the 1940's and World War II. When the US Navy Bureau of Ships was looking for an inexpensive deck chronometer for use on Navy vessels, Hamilton responded. Ships at the time had to rely on accurate timepieces not only for Navigation, but also to synchronize movements with other ships for example in supply convoys, radio discipline and so on.  Hamilton Model 22A mass produced (yet nevertheless accurate) ships chronometer was an important detail to help keep ships moving and supply lines going.

The challenge was nothing new: an English carpenter by the name of John Harrison was the first to build a successful clock that actually worked on a ship moving in all 3 dimensions. In the year 1761, John Harrison's famous "Chronometer #4" was successfully taken along during a sea voyage to use accurate time as a method of navigation (Longitude). Harrison proved that it was possible to create a timepiece that was both accurate enough to be used for navigation aboard a ship and small enough not to interfere with the ship's operation. Harrison’s clock however was extremely complex and difficult, thus expensive to reproduce. So in the 1780s and 1790s two great rivals, John Arnold and Thomas Earnshaw developed a new form of chronometer that could be mass-produced. Earnshaw invented a particular form of escapement with a device called a "spring detent" and a type of balance wheel that compensated for changes in temperature.

The Hamilton Model 22 and inner boxSo how did Hamilton address the issues at hand in the 1940's? How did they come up with ways to keep the watch wound properly, avoid that an operator might setting the time by mistake when winding the watch, keep the movement running accurately in different positions and at different temperatures? 

The new Hamilton deck chronometer was designed and built specifically Movement drawings (1)to meet themovement drawing (2) needs of the U.S. Navy. At a massive 35-size, it was by no means a small watch but nevertheless it was smaller and constructed simpler than the famous model 21, making it perfect for mass production. The movement inside the "Model 22" is a manual wind 21 jewel lever escapement chronometer movement with a Breguet style overcoil hairspring. A 60 inch long mainspring insured a steady amount of power to the gear train and a biaxial thermal expansion balance wheel as well as an Elinvar hairspring are responsible to keep the balance swinging at the same pace, independent of temperature. A power reserve indicator as well as about 48 hours of power reserve helped keep the chronometer running.

Explosion drawing of the watch and boxThe whole package was typically stored either inside a box with gimbals to keep the watch dial-up even during extreme roll and pitch of a ship. However, another version looked more like a pocket watch and was kept inside a padded box without any gimbals, but a glass covered opening that allowed to see the time without opening the box.

An ingenious "pin" on the outside of the watch case at the 11 o'clock position needed to be depressed before the crown could be pulled out in order to set the time; this simple "safety device" prevented accidental time setting or change of time when winding the watch.Instructions for setting time


dial and hands drawingThe dial of the "Model 22" was an off-white color (more of a silver color in the civilian versions produced after the war) with black printing. No luminous material was used on the dial or the large black "spade type" hands. A unique and oversized crown with a groove in the middle placed in between thick crown guards makes the Hamilton model 22 instantly recognizable while making it easy to wind the watch or to set the time, probably even for the large fingers of a rough sailor .  

An acrylic (plastic) crystal in a coin edge bezel that is simply screwed onto the watch case covers the dial, making it a breeze to replace the crystal even without special tools should the need ever arise. The back is easily unscrewed as well and a soft iron cover protects the movement from magnetic fields.My Hamilton Model 22The movement

The movement itself is nicely decorated with Geneva stripes. Its designation is engraved and states "Hamilton Watch Co. Model 22,  21 jewels,  Adjusted to Temp & 8 positions, Made in U.S.A." and in my case " US NAVY - BU Ships 1942" as well as the individual serial number. A fine regulation (that reminds me a little of a swan neck regulator somehow) helps adjust the regulator lever in small increments to regulate the movement to perform to chronometer specs even today.

The Hamilton "Model 22" is a classic Marine Chronometer and Deck Watch that certainly played a significant role in American horology, so it was only a matter of time before someone decided to pay homage to this watch and to come out with a wristwatch in the tradition of the Hamilton Model 22.

continue to Part II

Founded in Mount Joy (Lancaster County), Pennsylvania around 1991, Roland Murphy's "RGM" watch company has long been an insider's tip for great quality American watchmaking. Roland Murphy originally went to school for clock making in Lancaster, PA at the Bowman Technical school. In the clockmaking course, he also covered pocket watches, which is how he discovered his interest in watchmaking. Roland ended up going to school at WOSTEP in Switzerland in 1986 and returned to the US to work  in the watch industry in product development for a watch group and for one of their brands. He worked on the design of new watches, placing orders for sample components like dials, hands and cases and discovered that he had a talent for putting together new designs and watches. So in the early 1990's, that talent turned into a business that today not only produces some of the finest custom timepieces, but is also well known amongst watch enthusiasts for quality service work. Besides the RGM line of watches, Roland started an endeavor to offer more affordable watches under the "Equation of Time" label, also known for a watch and dive watch forum with the same name on the Internet.

I don't recall when I first heard about the idea for the EOT model 22 on the watch forum. However I do remember seeing the first drawings and hearing about some of the ideas for the homage watch during a get-together of watch enthusiasts in Lancaster, PA at the "Convergence" event in 2003. At the time, a watch under at least 40mm in diameter didn't appeal to me at all and my requests to consider a larger case size went unheard. The following year, at the "Convergence" meeting in Lancaster in 2004, Roland officially introduced the model 22 and I finally had a chance to check it out "in the flesh" and to strap it on my wrist for a personal "test ride".

Well, I shouldn't have done that. This is the second time something like that has happened to me (the first time was trying on a Panerai "just for size" during a vacation in London in 2003 causing me to start saving my watch funds for a few months until I was finally able to buy my first Panerai) so what can I say: I fell in love with the watch right there and than.

Roland and Rich really tried everything to stay true to the spirit of the Hamilton Model 22. From the look of the dial on their homage watch, the hands, the crown and crown guards to the packaging with a rich wooden box with a thick leather strap just like on the original deck watch box, part of the "Limited Edition" package (see photo on the left, photo courtesy of EOT).

The "Limited Edition" sells at US$ 2,200.00 and offers the watch on an alligator strap with an inscribed case back and individual serial number (one of only 50 pieces). Furthermore it comes inside the wooden presentation box in the tradition of the Hamilton Model 22. The other version offered by EOT is the "Standard Edition". For US$ 1,800.00, it comes on a regular leather strap (with quick change spring bars), a steel case back without inscription / individual serial number and a pouch and outer box. An additional US$ 145.00 you can get a sapphire crystal case back and US$ 75.00 will buy you a different bezel (smooth) to change the looks of the watch.

Well, I went with the "Standard 22" plus the crystal case back and received it as a Christmas present from my wife this past Christmas. Since than, it has changed my views on non-black dial watches as well as watches that are less than 40mm in diameter and the EOT model 22 found its way onto my wrist surprisingly often even against some serious competition (see photo on the right, photo courtesy of EOT) .

The following is my review of the watch and features after a few weeks with the timepiece.

continue to Part III

Equation of Time (RGM) "22 Standard"

Watch Brand: Equation Of Time
Watch Model: "22 Standard" 
Serial No.: none
Date Purchased: 12/23/04
List Price: $1,800.00
Date of Review: 1/23/2005

Matt's Watch Rating
Movement 20/20
Case, Crystal and Crown 20/20
Dial and Hands 10/15
Accuracy 15/15
Strap, Buckle or Bracelet 5/10
User Manual and Packaging 1/5
Comfort 5/5
Value 10/10
Overall Rating 86/100


The original and the homage






EOT Model 22


I have only had the model 22 since last Christmas and am still in the "honeymoon phase" with this watch. The model 22 means more to me than just a unique new timepiece as it will forever remind me of two "Convergence" gatherings with fellow WIS in Lancaster, PA and the friendships that were struck during these weekends. Nevertheless, here are some of my impressions about the watch.

EOT Model 22


Case, Crystal and Crown

Dial and Hands

    Hamilton's original used black spade hands and the hands on the EOT model 22 look very similar to the original. One of the first things I noticed was that the minute hand of the EOT is a tiny bit longer than the minute track and extends over the edge. I am not sure if this is deliberate or a result of a missed tolerance and to be honest, I wasn't quite certain initially if this was going to bother me long term. However it seems that close-up photography exaggerates the issue and during regular use, I haven't even noticed it at all.  The dial itself is an interesting silver gray color with a texture that sometimes looks bead-blasted, sometimes looks like it has been brushed in one direction. It seems to change color depending on the light, from a silver white to a warm off-white which contributes to its beauty. Under a loupe it almost looks like the dial printing is actually etched into the dial. No logo or manufacturers name adorns the face, just the "Lancaster, PA, U.S.A." and "Chronometer" designation as well as the "Up / Down" indications on the wind indicator. I did notice a small irregularity in the close-up shots of the number "20" in the sub seconds dial; not sure if this is an issue with just my watch or if the top of the number "2" is meant to be thinly printed on all dials. The hands are painted black with some sort of powder coating, which allows them to keep a classic matte black (anthracite), sometimes slightly brown appearing look rather than a modern shiny and more reflective "flashy" plastic look. A detail that I really appreciate on this watch!

    Closeup Dial and Hands


    The 21-jewel, hand-wound "SO 7001RM" came to me running 5 seconds fast per day on the wrist with a beat error of 0.3ms and a 326 degree amplitude. After about 4 weeks it is running now about +2s/24h on the wrist and still has the same beat error and amplitude. I am very happy with the performance so far, well within COSC chronometer specs and I can live with the fact that the movement doesn't "hack".


Strap, Buckle or Bracelet

    In spite of its smaller size, the EOT model 22 has a 24mm lug width, just like the 44mm Panerai models and thus allows me to take advantage of all the 24mm straps that I have already collected for my Panerai (and all the interesting, often exotic 24mm straps that are being offered on the market in 24mm). The generic leather strap that came with the EOT "Standard 22" was nothing to rave about. While the "Special Edition" comes with a genuine alligator strap, this one simply comes with a padded leather strap (choice brown or black) with a quick-change springbar. The buckle is generic as well. While a nicer strap IMHO would have probably been fit for a watch at this price level, I understand the need to differentiate the "Limited Edition" from the "Standard Edition" and luckily have a few nice straps to wear the watch on. Currently I am switching back and forth between a padded alligator strap with large scales in tan color with white stitching (Breitling style, see below) and a thick alligator strap (Panerai style, see at the top) with large scales in black with matching black stitching.  

    Gator Strap

User Manual and Packaging

    The EOT model 22 came inside a black EOT leather pouch and outer box. No manual or additional warranty papers were included  (but I believe that EOT/RGM has no problem tracking these watches to their respective owners for their 1 year warranty). The Packaging for the "Standard Version"  is nothing fancy, but than again I didn't want to spend an additional US$ 400 for the "Limited Edition" with the nice wooden box, so I have nothing to complain about in regards to the basic packaging.


    Really not much to say about that one; the low and nicely down curving lugs set the watch low and comfortably on the wrist. All edges and corners are smooth, nothing that feels in the way. A note though: I am wearing my watches on the right wrist and have never been bothered by the large crown and crown guards, so I can't say with certainty if these could potentially be an issue and dig into the wrist/hand when the watch is worn on the left.  


Dial Closeup



This watch review was written by  Matt V.

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