After my last post of a Thin-o-matic with a micro rotor movement I decided to take it easy on myself so I could recover. I have a couple of manual-winding projects to get to but they're waiting on new crystals. The best I could do was come up with a more traditional automatic, but it's an interesting model nonetheless.
The 1964 Accumatic A-602 is a nice looking model, so nice looking that it's hard to believe it was a one-year wonder and only made for a single year.
You can't really tell from the catalog depiction what makes the A-602 so interesting. It has a three-tone dial with a parchment-colored field and a two-part silver chapter ring outfitted with gold hour markers. There is a lot of sparkle to this watch, so much so that I would be tempted to put one of those faceted crystals on the watch, just so I could see what it looked like.
Tucked inside the case is a 17 jewel 689 movement made by ETA.
My project watch arrived in average condition. It could stand a new crystal and the Speidel bracelet looked nice but it has to go, as the expansion ends that are designed to accommodate various lug widths and are spring loaded. They will wear grooves into the lugs over time.
The case back has a deep pie-pan shape - a sure sign there's an ETA movement inside.
Like a lot of Accumatics, the A-602 opens through the crystal. "The Claw" is my go-to tool for this type of application and even though the last watchmaker glued the crystal on, I was still able to break it loose. The things people will do to avoid buying the right part... this crystal is about 0.5mm too small for a proper fit. That's okay though, I was planning on replacing it anyway.
The gaskets in the crown aren't very good so some moisture has gotten into the stem tube and rusted the stem slightly. Otherwise the movement looks good.
However, it sure was dirty... check out how cloudy the cleaning solution got after 6 minutes in the ultrasonic. It's rare that one movement will make a baby food jar of cleaning solution this dirty. This is why it's always a good idea to get any new project watch overhauled before wearing it.
Everything is cleaned and then rinsed twice before being thoroughly dried. Now it's time for reassembly with fresh lubricants. This movement uses two types of oil and two types of grease in various places.
The partially reassembled movement is purring away so it's off to the timer to see how well it's running.
The amplitude of 230 is great, the beat rate is a little fast and the beat error of 1.7ms is acceptable in most situations but this watch is very easy to adjust so I can really fine tune it.
First I'll tackle the beat error. That's adjusted by moving the position of the hair spring stud on the balance cock one direction or the other. If it gets worse, I need to go the other direction.
There - it doesn't get much better than 0.1ms, although 0.0 is obtainable. It takes such a small adjustment that it's just as likely that I make it worse. So I'll stop here and move on to adjusting the regulator . By moving the regulator I can make the hair spring ever so slightly longer and slow the beat rate down.
The two lines look like one line since the beat error is so low and they are almost horizontal so I'll stop here. Four seconds fast per day is a totally acceptable beat rate for a watch from this era, in my opinion.
The oscillating weight goes back on the reverse of the movement and the dial goes back on the front. Then the assembly can go back into the case so I can use the crown to position the hands at 12:00 when I install them.
A new 29.3mm GS PHD crystal will do nicely to seal the watch and protect the dial and hands.
A new lizard strap completes the watch's restoration and this A-602 is a true beauty.
And best of all, it came with its original box and paperwork. Thats always a nice addition.
Thanks for visiting my vintage Hamilton watch blog. I like to restore US-made Hamilton wrist watches back to their original glory and share my experiences with other enthusiasts. Use the "Search" space below if you know what model you're looking for. Feel free to leave polite comments or questions in the spaces provided. Also check out my "watches for sale" on my Etsy site - the link is on the right, just below.