GruenWristwatches . com 

Dedicated 100% to Vintage Gruen Watches... "All Gruen, All the Time"

Feb 2018

The latest Gruen movement serial numbers to fall, the 440 AND the 295 Curvex movements...  The lookup table is located below and on the Serial Number page.
Serial   Year
0        1940
2000     1941
3000     1942
6000     1943
9000     1944
A 0000   1945
A 4000   1946
A 7000   1947
B 0000   1948
B 6000   1949
C 0000   1950
C 2000   1951
C 5000   1952
C 9000   1953
Happy New Year 2018!

Another year, another new Gruen research tool.

The Gruen Movement Catalog Caliber-Date Table.

There's something in this table for everyone as it applies to every Gruen watch you'll encounter*    More info about this table in the Movement Catalog section. TEXT version now online!

*up to about 1955

New Gruen Movement Map

Browse information about Gruen movements like never before using the new Gruen Movement Map.  Learn the approx age of your movement by looking up the movement's start of production date. Visually locate your movement on the map.

Great for eBay sellers that need to quickly find movement Caliber Numbers for their movement listings!

Shortcut-dating of Your Gruen Watch

Don't want to take the time to get a really accurate answer on the tutorial page?  OK, let's ease you into it.

1. Find the Style Number Date of your watch using the calculator below. Write it down.

2. Find the movement caliber number on your movement. Use it to find the date on the Caliber-Date Table.  Write it down.

3. Find the date your Case was manufactured. Look up the serial number on the Serial Number Page.  This is THE most important of the dates as it's really your watch's "birthday". Write it down.

4. Bonus points.  Find the serial number on your movement.  Look it up on the same serial number page as #3. Write it down.

Now you want to 'weight' your dates. The most weight goes to the Case date, #3. It's pretty much your answer if you found it.

If no Case Date, then the other 3 become your best guess.  The movement can be swapped, so careful with the date.  The Style Number and the Caliber-Date tell you the OLDEST your watch can be.  It will never be older than the Style Number.

Awesome... you're now a Gruen researcher!  

Online Style Number Date Calculator

Date your Gruen using Style Numbers, described in the article below. 

The Style Number Date tells you the MAXIMUM age of your watch. Your watch was NOT made before the Style Number Date... period.

Enter your Style Number in the box below to find your watch's date and additional Style Number information. You are encouraged to read the article for important information about using Style Numbers.

If your case has 2 numbers, verify that your watch's movement caliber matches one from the list of calibers the tool provides.
(2) In some cases, the Caliber and Style Numbers are reversed

Online Universal Case Serial Number Decoder!

Play stump the decoder... enter your Gruen's case serial number
See if it can guess the manufacturer date manufactured
HIGHLY Experimental
  Use with CAUTION

Ligne <---> mm Conversion Tool
Calculate the value of your Gruen in today's dollars using this
Search our site to find stuff quicker!

If you find something in these pages that both excites and motivates you, please share it with others!

Mobile and tablet users - This site best viewed in  "Desktop mode". The fonts are fairly large and the galleries work better in this mode.

Gruen Movement Finder - Quick reference tool that tells you basic info and where to find more info.  Expect better things soon as this is just a portal into the data....
BOOKS to help with identifying and repairing your Gruen watch are now available on Amazon as well as Lulu!  Lulu has the entire list of Gruen books while Amazon is a subset.  See coupons further down this page or on Lulu's homepage for more savings!

A new lower cost, soft cover version of The Gruen Watch Catalog is now available.  

The Front Page... highlights

Nov 2017 - Since it's been a few months since the last major update, the addition of the Gruen Map of Movements, part of the larger Gruen Movement Catalog project.  This Cataloging project is a significant on, as each movement much be located, photographed, had the data collected from it, and much more research about when it was made, etc.  I'm also working on some sophisticated identification tools.

What this all means is that the site may feel a little scattered.  Where there is plenty to discover here, no everyone wants to spend the time 'discovering' and wants to get on with getting their questions answered.  I totally understand if there is some frustration along the way. I appreciate hearing from anyone with feedback.  It helps me make a better site for you. I will work to get a couple of smaller tutorials or posts of historical material between now and the opening of the larger projects areas.

Recommendation for a watchmaker for your broken or poorly running Gruen :-)  Added to the "links" page was my favorite watchmaker Time Restoration. I have no trouble nor hesitation in recommending you give him a try.

New movement serial number logging form! Want to help out with the current caliber 440 + Wadsworth case effort?  Then fill out the form on the serial number page and your data will get merged into the graph on that page.

Announcement of HUGE watch/clock material auction!

Addition of a handy Inflation Calculator makes it easy to understand the dollar figures found in old ads and price lists.

RARE treat! The family of Gruen designer Richard G. Gersch has been SO amazingly generous in their submission of photographs of materials saved by Richard after he left Gruen in 1954. The new homepage graphics come from these materials. Watch for more!

NEW tool - Gruen Case Serial Number Decoder tool launched on homepage and on Serial Number page.  Use with caution, but use!  Provide feedback on the about page if you want to help!  Please be hyper-careful when submitting data.

Movement Information Finder tool now operational!  Check it out in the new Movement Catalog.

Ligne conversion tool! Want to know how many Lignes your movement is? Just use the new handy tool on the homepage and in new Movement Catalog

The Caliber 440 Curvex movements' serial numbers have been [maybe] [partially] decoded!!  Exciting news that we can finally determine the date a cal 440 movement was manufactured.

More research and digging into the high res photos. Matching them against the book "Worthy Company". Read about it here.

Added an online index for all of the movements that can be found in the Gruen Repairer's Reference.

Gruen Parts Requests If you're having a hard time finding a part, maybe we can help.

Movement Catalog additions. It's growing... slowly.  Looking at making a WALL CHART of Gruen movements. Fun!  Since I've got these high-resolution photos, why not blow them up and put something useful on them??  It's likely I can have a choice of several backgrounds.

Fred Gruen's watchmaking school notes... all 97 pages worth are posted and readable online.

Added caliber 510 mainspring size on the mainspring reference page and updated the reference PDF to version 5. The 510 mainspring was only sold as a barrel and mainspring sub-assembly. Gruen never published the size of the spring nor could you buy it separately from the barrel.  Weird.  Spoiler... the 510 uses a Dennison 2.5 x 10 x 14 inches.

Site cleanup.... a number of old webpages that should have been removed remained in the sitemap are now password protected to stop the search engines from crawling them. No great conspiracy here to see.

Advertising... yes, ads have been added here and there on the site recently.  
I know some people are furious when they see ads. If you're one of those people and prefer to help keep this site running, then I've added a convenient Donate button on the About page. My goal has always been to provide people with as MUCH Gruen information that I can either buy, beg, or research, for as long as I can.

It's already been a BUSY NEW YEAR!

NEW tools for dating your Gruen watch!

Serial numbers for cases made by Gruen, Keystone, Star have just been released. You'll find them on the Serial Numbers page.

More Gruen Annual reports. A generous reader has located and provided to me the "missing years" and in the process almost doubled the number of pages to 342 pages!

And, a new "series".... 

"Fred's Big Adventure!"

In this series of PDF posts contains pages from Fred's hand-written diary chronicling the train trip he took with George Gruen in Aug of 1934 (I think). The trip was from Chicago to Yellowstone and was over a week. There are 200 small hand-written pages. The handwriting is difficult to read, so I'm having this document transcribed.

We will all learn together what kind of writer Fred Gruen was as the pages are being transcribed and released a few at a time.

Keep checking back as more pages are added every day or two! 

More free stuff! An early version of the Gruen Horological Text

I'm making available another newly discovered Gruen document. For the price of $0.00 you can download or read online the Gruen Watchmaking Institute's course materials. You'll find the 88 page document on the page titled FREE Watchmaking Course.  Enjoy and happy watchmaking!

Former Employees' Relatives....

Did your parent work for Gruen???

Have you discovered a box of Gruen stuff from a former employee and want to get more information about what you have???

Then CONTACT ME!  Please!

I've helped several families figure out not only something about the items they own, but I can sometimes point them to employee newsletters that described what life inside the company.  Head over to the "About" page and leave feedback with your contact info.  You would be surprised at how one small bit of info can help solve some very big questions, longstanding questions.

A plea to eBay sellers....

You can help Gruen research GREATLY with your ebay Gruen watch listing.  PLEASE consider taking clear pictures of the case interior & movement and embedding them into the listing itself.  This is critical so that researchers can save your listing in PDF format and pull it up in the future for studying.  

Also, if you can include the serial numbers for the movement and case it will be of GREAT USE to Gruen researchers trying to do things like, oh, decode the serial numbers.  In fact, the recent publication of serial numbers for 4 case manufacturers couldn't have been completed without the help of ebay listings. Please check out the Serial Numbers page so that you can learn the location of the serial numbers AND their PREFIXES! PLEASE check closely for a prefix letter or number.  It may be unpainted, faint, and positioned AWAY from the main serial number itself.  

The Caliber 440 Curvex's movement serial numbers were recently decoded entirely through the use of ebay listings.

Yes, these numbers sometimes don't mean anything, right now, but they most certainly will in the future!  These sequences will be decoded so that more accurate dating of Gruen watches can be completed.  Thank you to all the wonderful ebay sellers that have been providing this information in their listings! 

Remember to check your serial numbers against the movement AND case serial number databases!  You may be able to quite accurately pinpoint when your specific watch was made!  

New discoveries are published every few months (if not every few weeks) so keep checking back!

Gruen Curvex Comet 1947 440 544
What's your first Gruen?

For me the watch to the left changed my life.  I restored it and put it up for sale on eBay.  But something about this watch spoke to me and I thought it was one of the most beautiful watches I've seen.  The dial is really creamy and deep.  The curved crystal that continued down the lugs that meet an equally curved and elegant case back.  I was hooked. 

Check out the "before" picture. International Dial did a phenomenal job. The results from restoration efforts are incredible, and I say that in an generalized way. Almost any watch can be brought back.

Then the real magic took hold when I started researching this new-to-me brand, Gruen.  What did I find?  Almost nothing... that's what :-(  That meant there was pretty much nothing but improvement ahead!!  Gruen was WIDE OPEN to be researched, discovered, decoded, and deducted. What a rare thing to us all to share.

This father and son family were brilliant and seemed to attract really good people to work with them, to see their collective visions through to reality. As you become more educated and read the details of what this Gruen family accomplished, it doesn't take long to see that these were geniuses at work.  

I hope you enjoy this site. Explore the many different facets that make Gruen unique among all other watches. It's an attempt to be a repository and library, tools and tutorials. Call it what you want... I call it fun!

All photographs, digital documents, movies, and any other digital material ( galleries, etc ) are copyright ©  2013 by  Second Hand Press.  
Permission for re-use or distribution, in any format, is not implied nor granted. Information contained here was purchased, collected, created and assembled for personal consumption.

If information here was obtained from other sources, explicit permission was obtained. Please treat their information with great care.