Restoration Workbench 1970 36mm Ricoh 040121 Medallion

Technical Terms Used in this Article

Balance – The wheel attached to the hairspring that oscillates back and forth as part of the escapement and is responsible for the accuracy of the watch’s time-keeping.

Cannon Pinion – A gear that fits tightly over the center wheel/second wheel axle to transmit power from the movement side to the dial side of the watch. It rotates once per hour like the second/center wheel.

Center Wheel The second wheel in the going train, driven from the barrel and rotates once per hour.

Fourth Wheel – The fourth wheel in the going train. It is driven from the third wheel and in turn drives the escape wheel. It rotates once per minute.

Going Train – The gears that run from the barrel with main spring inside and end in the escapement wheel.

Hour Wheel – A dial-side wheel that rotates the hour hand. Driven by the minute wheel.

Keyless Works – The manual winding, time and date setting mechanism attached to the crown and stem.

Main Plate – The central layer of the movement to which all other components are fixed.

Minute Wheel – A dial-side wheel driven from the cannon pinion that in turn drives the hour wheel.

Motion Works – The gears that rotate the minute and hour hands using power transmitted from the going train.

Post – A short axle extending from the main plate on which a wheel can rotate.

A 1970 Day-Date Copy from A Japanese Camera Maker

I’d forgive you if you thought this was a Rolex 6611 Day-Date after a quick glance. It is not, of course, but the maker’s name does begin with R. This is the Ricoh 040121 Medallion from 1970. A 50-year old blatant copy of the Rolex! And that is why it caught my eye: while it maybe an homage, it has aged and patinated just like Allen’s vintage 1970s Datejust due to the yellowing of the nitrocellulose dial lacquer and other materials. It’s all the slightly different silvery hues that Allen’s watch exhibits that makes that watch so great to my eyes. So when I saw this Ricoh for auction in Japan, with its multi-shade, silvery patina and its day-date looks, I decided to buy it, even though I knew nothing of Ricoh watches, nor whether it was even running. 

Ricoh Medallion
Fresh from a Yahoo Japan auction – the 1970 Ricoh 040121 Medallion

It was not running.

On arrival the condition of the watch was a little disappointing to be honest. The Japanese description translated by Google mentioned that the time could not be set and this was true, but it said nothing about the watch not running at all. Duplicitous ad copy at its best, and in my experience, quite untypical for a Japanese auction.

The Mechanical Problems I Discovered

Any attempt to wind and coax the balance into motion with a puff of air failed to keep it in motion for long…but at least the balance began to swing and move the escapement. Repeated puffs of air even kept the balance moving and advanced the fourth wheel, hidden below the winding mechanism, sending the second hand on its rotational procession dial side. A glimmer of hope. Perhaps the going train was simply gummed up and could not overcome the resultant friction to keep running.

The ineffective keyless works (setting mechanism via the crown and stem), however was a mystery. On initial inspection I had no idea why I could not move the hands. Perusing Japanese auction sites for Ricoh spare parts revealed a large number of setting levers, yokes and springs for sale, making me wonder if these parts frequently failed.

The 040 movement with winding rotor removed. Note the crown seal stuck to the crown tube.

Preserving Patina

As for the cosmetics, the case, bezel and dial exhibited the slightly different shades of silvery-grey that I was after. The crystal was cracked and smashed as the auction photos had shown but the dial was damage-free and the bezel, the only plated part if the case, looked almost new. The bezel and crystal separated with a little persuasion from the case knife revealing no signs of corrosion or water ingress which elevated my mood. The original case finishing was just about visible and appeared identical to the Rolex 6611 ‘inspiration’ with polished sides and brushing on top.

Buried Treasure & Bad Crystals

The crystal would definitely need to be changed, so while pondering the non-functioning keyless works, my thoughts drifted to how I would source a new one. Measuring the crystal gave in inner radius of 29.6mm and an outer radius of 30.9mm. I suspected tracking down a Ricoh replacement was going to be a tricky task. More research would be needed but I wondered if an aftermarket crystal for an actual 6611 would fit. The idea of a vintage Japanese homage being so close that a Rolex crystal would fit amused me. The Ricoh measurements suggested that a Rolex replacement crystal might indeed be a close fit. I did not measure the location of the cyclops but assumed it must be in about the right place if the rest of the crystal fitted. I order a few replacement Rolex crystals calculating that if any fitted, they will have been a lot easier to source than a Ricoh crystal.

With the movement removed from the case, the dial looked in even better shape. A perfect dial under a terrible crystal is what I look for when buying vintage watches at auction, and while I can never be 100% sure based on the often-fuzzy photos, this time I definitely rode my luck. I always get a thrill whenever I remove a beat up crystal and find a pristine dial and hands underneath. It always feels like finding buried treasure.

Ricoh Medallion dial
The dial was in good condition beneath the scratched up crystal

Releasing the movement from the case, revealed some crud and damage around the the outside of the dial but nothing that will be visible once the watch was reassembled.

Disassembling The Movement (Cal. R.040)

The movement Cal. R 040 automatic, has 21 jewels with a quick set date (but not day). The date is changed by pulling out the crown to the second click and pulling again to change the next day. But on this example that feature definitely did not work.

I started disassembling the movement side first. Everything was pretty shiny and the seals were still soft so perhaps this watch had even seen a service in its recent history. However, I quickly found the jewels were dry, confirming this was not the case.

Ricoh Watch Disassembly

The automatic winding mechanism comprises quite a complex bridge with two wheels plus a reversing mechanism. With that removed, the movement is absolutely conventional requiring a standard strip down. With the second, third, fourth and escape wheels removed, I switched to the dial side.

The dial side also proved to be fairly conventional. The expected springs were there and none escaped the workbench as I progressed – Hurrah – I must be getting better! However, removal of the date disk cover revealed a true horror below which explained both the non running condition and the inability to set the time.

The badly corroded minute wheel

The hour wheel of the motion works was totally corroded onto the cannon pinion below it. The minute wheel to the side was covered in brown rust and frozen to its post. Moreover, some of the teeth that originally meshed with the intermediate setting wheel were now completely missing, broken away by trying to drive that corroded hour wheel and cannon pinion from the winding stem. The state of these wheels completely explained why I could not move the hands when I pulled the crown and turned it – the setting wheel was rotating with the crown but there were no teeth left on the next wheel to turn the minute and hour wheels.

This level of corrosion deep in the center of the movement was completely unexpected. There was no sign of it on the movement side but from the opposite dial side I could see that the water had traveled along stem and sat on the minute wheel where it seems to have wicked underneath the hour wheel and up onto the cannon pinion. Where it must have sat for a very long time to cause this level of damage. 

The hour wheel was stuck fast and could not be moved and upon closer inspection the movement side did contain a single clue to the disaster a couple of millimeters away. The center wheel was no longer tight on its pinion, and was rotating freely, forced loose by a mainspring trying to turn the center wheel against the seized motion work on the other side. 

In a vain attempt to salvage something from the remains of the movement, I soaked the remains in automotive penetrating oil for 24 hours! This is common practice on vintage cars and on this particular vintage watch, the problem was the same, only the scale was different. The soak did remove a lot of the corrosion and freed the minute wheel but the hour wheel, cannon pinion and center wheel pinion were firmly stuck. In the end I had to cut through the cannon pinion and center wheel axle to remove them from the main plate. However, the damage did not end there. Once the remains of the cannon pinion were removed, there was no center jewel. I found it, broken in pieces, encrusted and embedded in the rusted remains of the cannon pinion.

Rusty Watch Movement

Admitting Defeat And Starting Again

It was time to take stock and admit that this movement, or at least its core, was junk beyond saving. I could replace the center jewel but I’d still have to source a replacement center wheel, cannon pinion, minute wheel and hour wheel. I was not able to find anywhere that sold spares for these movements, but there did seem to be plenty of movements available inside other Ricoh watches.

The 040 caliber in this watch is related to a large family of Ricoh movements that were produced from the late 60s on. I assumed that many parts were shared across them all as this is what tends to happen in these families of movements. Small changes are made in the design from one series to the other but most components remain the same. For example, the 041 movement appeared to be a 040 with a conventional horizontal date window at 3 instead of the sector window at 12. I thought there was a good chance that the only component of the movement different between the 040 and 041 would be the date disk itself. With no spares on hand, I had little choice but to bid on a small selection of potential donor watches and hope for the the best.

Donor number 1

One week later, donor watch 1 arrived from Japan. The serial number indicated that the movement was a 041 which I suspected (hoped?) had the same basic movement inside. While the dial of the donor was trashed the movement was spotless upon opening – a good sign. Stripping down the donor watch confirmed the 041 movement was identical to the 040 bar the day disk. Most importantly, the base plate was complete with its center jewel and a pristine canon pinion. So good was the donor movement, that I decided to use it to restore the watch instead.

Donor main plate and pristine center jewel

Once the donor movement was cleaned, I started on the rebuild. However the thought of tackling the keyless works was worrying me. I had now taken apart two of these Ricoh movements and it was still not obvious to me how the day and date quickset worked. There were some levers, some pivots and some springs but both times I had disassembled the quickset, it had felt more like a collection of loose parts rather than a precise mechanism. Therefore, I uncharacteristically started with the dial side of the movement.

After a bit of trial and error and a measure of common sense, I worked out what went where and the slightly complicated quickset mechanism went together slowly but surely. Moving on to the motion works, however, led to a small disaster. The extremely small screw that secured the date finger to the date disk driving wheel snapped, leaving the threaded body in the top of the post. Rather than trying to drill out the remains of the screw that were much less than 1mm in diameter I chose to re-use the post from the original watch, pushing it out of the old rusty movement and into the donor movement with my jewelling press.

Restaking the post for the date disk driving wheel

The rest of the reassembly went smoothly without any issues and, as is my normal practice, I put the bare movement on the timegrapher. The initial numbers looked great… +/- 7s with 285 degrees of amplitude and almost no beat error. Excellent results even if I do say so myself, so I left the movement to run in on the timegrapher overnight.

The movement  stopped overnight.

Diagnosing My Own Repair Work

I ran through my mental checklist of possible faults. Was it out of power? It wasn’t. Could the balance be cajoled into oscillating with a little airflow. It couldn’t. Clearly something had blocked the going train somewhere. I pulled the crown and moved the hands backwards – the watch started running again. I adjusted the hands forwards again and the movement bound up. However, this time looking at the dial side, I could see why. The day wheel finger was jamming against the end of the lobe of the day wheel rather than contacting the side of the lobe and pushing the day wheel around. It seemed to happen about one time in four because the lobe was occasionally being knocked by the date driving wheel and not just the finger. Changing the date driving wheel and the lobed wheel seemed to fix the issue but in testing I suspect this is a bit of a design fault with the movement… the slightest interference between the finger wheel and the lobed day wheel would be enough to completely lock up the movement requiring a partial strip down to reset. The solution I think would be an additional spring to ensure the same rotation of the lobed wheel each time.

Dial side with potential date finger – lobe interference issue.

I concluded  that with the replacement parts, the movement was now reliable enough to continue with reassembly and I put on the cleaned dial. Into the final stretch now and it really looked good coming together. The dial and hands were always in good condition on this watch and so it was a delight to see them fitted back to a working movement.  

Ricoh 040 movement
All back together apart from the winding rotor

Now About That Crystal

So back to the issue of a replacement crystal. As expected, the correct Ricoh crystal could not be found anywhere so I contemplated using a Rolex replacement crystal. After some trial and error, I did find a Rolex crystal which fit but it ended up being the slightly larger 25-135 for the 16000 models rather than the smaller 25-118 for the 1603/6611. The result was a little taller than the original Ricoh crystal. I will have to live with that… while smiling to myself that this vintage Rolex homage watch has a Rolex replacement crystal.

With the watch fully back together I realized that the stem seemed to be a millimeter too long. As it was, the seal inside the crown would never seal against the crown tube effectively. Could this be the reason for the initial state of the watch? Remember the center wheel, cannon pinion, minute wheel and center jewel were all rusted into one giant lump because water had seeped down the stem and sat at the very center of the watch. Apparently, here was the root cause of the watches initial failure: either a bad stem from the factory or a misjudged replacement during service. Removing the crown, trimming the stem, replacing the seal and refitting the crown fixed the sealing issue and finally the watch was complete.

Ricoh 040411 Medallion
All back together but with an ill fitting crown


In conclusion, the Ricoh 040 movement impressed me with its efficient sophistication even though the movement was devoid of any hand finishing and somewhat industrial. The workmanship on display was all in the movement design rather than the manufacturing. The day wheel and the keyless work appear to be the only exceptions to this effective approach both proving to be a little unreliable. Ricoh is a watch maker almost unknown outside of Japan, and one that I had no prior experience of so it was gratifying to see just how well made these watches were in 1970 and how well they can be made to run today.