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Thoresen Recipro-Register

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Today I wrapped up work on a Thoresen Recipro-Register Chronograph.  Sounds like an exciting piece doesn't it?

The Thoresen Recipro-Register is a Landeron 48 calibre chronograph.  The one I'm servicing here was sold in about 1953.  The watches were acquired back in the day via mail order for a bargain price of $29.95 USD.  This is another "everyman" chronograph much like the Chronograph Suisse of the same period.  I picked this one up from the Goodwill for a fair price as as it kept poor time and had a broken Speidel bracelet. 


This is quite a small watch compared to the chronographs of today.  Diameter, including crown, is 37mm and the space between the lugs is only 16mm- that's quite a narrow strap.  It's a men's watch but today would be quite at home on a woman's wrist as well.


I knew it was running fast before I even put it on the timegrapher but I was pleased with the amplitude.


The normal dirt and grime had accumulated around the caseback but the inside was immaculate!  Only a tiny bit of rust staining at the top where water had entered at the pusher.  The movement is marked Orator Watch Co. as is the caseback.  Under the microscope a bit more dirt is visible but the screws look like they may have only been turned once in their lifetime.  It's here that I get a lump in my throat.  I almost feel bad putting my amateur hands on this one!


I start breaking the watch down.  The hands and dial come off first.  The dial is in wonderful condition as well.  The lime is radium based so extra care is taken.


Dial side of the movement is utilitarian but clean.


After snapping some reference pictures of the front and back I'm called to dinner.  The movement goes under the glass for the next day...


And the camera batteries go dead!  No pics of the breakdown I'm afraid!  There wasn't much to discover though.  The movement looked quite good and there were no obvious issues noted.  Probably just a cleaning and lubrication will do the thing.  I put the movement though the L & R and start reassembly.  Despite the nice amplitude registered before, the mainspring looks spent.


Luckily I have a replacement at the ready.


The gear train goes together simply enough.  There's some rust staining on this plate as well.  I tried rubbing it out with pegwood but let it be when elbow grease wasn't enough.


The pallet fork (installed above) is a bit different from those I have seen before- clear rubies.  It's not really a big deal but something different.  Clear cap jewels are something I loath.  They are very easy to lose.  Luckily this watch only has clear jewels on the pallet fork!  (Please note that the picture below was taken before cleaning the pallet fork!) 


Dial side is assembled next.  The keyless works is properly greased and reassembled.


So far things are looking good but there is one jewel setting that is bothering me.  I take a better look at it under the microscope.  


If it looks funny that's because it's chipped.  The chip is on the oil reservoir side.  The pivot hole is still properly rounded however.  I have a Seitz tool for replacing the jewel but no replacement jewel readily available.  Seeing as I own this one and just want to get it off my desk, I continue with assembly while making a note to the fix the jewel later.  On the timing machine I discover that there appears to be no impact.  With the basic works back together i start on the chronograph.


I've taken to returning the screws to the plate after disassembly so that they are readily available for reassembly.  This has saved me a lot of time hunting for screws.  Despite this, I still managed to mix up two pair of screws!

The movement is reassembled and re-cased- how did I forget to take a picture of the reassembled chronograph movement?  It took quite a bit of effort to get the chronograph to work flawlessly; there are three eccentrics that needed adjustment to get the gears to mesh just right.  The flyback lever was also an issue until I realized I had mixed up a screw and needed to swap it with another longer shouldered screw.  Lastly the sweep second hand had a tendency to reset a few degrees to either side of 12 o'clock when operating the flyback button.  I fixed this by removing the hand and giving the tube a light tap with a stake to tighten up the post.  Now tightened it always returns true.


A new crystal completed the effort.  What a darling!


Now for the bad news, and hopefully the community can help me out here.  Despite my best efforts I could not eradicate the beat error.  I figured anything 1.0ms or less would be acceptable considering the age of the watch and in one position I can get that but the rest of the positions are not great.  

Screenshot 2016-04-27 23.26.01.png

The cracked jewel is the lower pallet jewel- I'm sure that could have an impact on the timing of the watch and that will be the first thing I fix.  Otherwise I'll be checking the balance pivot and the shake of each gear in the wheel train.  If there are any other ideas I'm open to hearing them too.  I wish I had caught this a little earlier but didn't check the watch in several positions before service or even after assembling the base movement.  I can attest that the pivots and gears are in good order though.

All in all, it is keeping good time sitting on my desk and I have to admit I'm smitten by it's appearance!

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That's a lovely looking watch and good write up Ry, very well done.  The first chronograph I worked on was a Landeron 48, so I have a bit of a soft spot fir them.

I do hope you get around to replacing the cracked jewel, it may well sort out the slight issues you have as well as prolonging the life of the watch.  I'm assuming you turned a few eccentrics by mistake during disassembly, I bet you don't turn them the next time you strip the movement.

keep up the good work!

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