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Miyota Automatic Service - "Three Screws to Rule Them All" Now for something completely different, a Japanese Automatic from Miyota. This is a budget driver's watch from a fashion brand called Scorpion, and I had no idea what I'd find when I removed the caseback :huh: Whatever! I just wanna work on watch movements, increase my knowledge, and the repertoire of movements I've had experience with. It's also a blessing to post these to help people with reference photos and walkthrough of various movements. When put on the timegrapher, it was quickly obvious that this movement was not running well at all. Extremely low amplitude, high beat error, and a graph that looks like the pepper in your mash potatoes :P Well, it happened to be a Miyota Automatic Movement ... I have no idea of the caliber, as there are no stampings on any of the plate ... beside the brand name. Once removed from the case, I pulled the Hands... ...and then the Dial. After that, I flipped it over and removed the oscillating weight to get a better look at the movement itself. Notice anything scary about this already?? There are only 3 screws holding the complete movement together!! :o Ack!! Visions of the Seiko 5J22A Kinetic "Auto Relay" , with it's 9 pivot gear train plate flashed before my eyes!! This was NOT going to be fun putting back together :P But I do so love a challenge. As per usual, I removed the tension from the Mainspring, and removed the Balance and Fork. Note: The red arrow is pointing to a very thin spring which you pull back to disengage the Click. Here's a closer reference photo of it after I'd pulled the plate off So as the title says ... Three Screws to Rule Them All .... Bam! The whole movement has to be located into ONE plate, that's only held by three screws ... this is not Rolex quality gentlemen ^_^ After tipping the movement up-side-down and telling the complete movement fall onto the desk (just kidding), you are left with only the Centre Wheel. Once the Centre Wheel Bridge was removed, the fault with the movement running so badly came to light ... RUST on the lower piviot! Rust also on the Pinion Over to the Calendar and Keyless Work ... looking way over complicated for a simple Date Wheel, as all the springs are there for a day complications as well; minus just the Day Wheel :( ... Gotta love cheap movements. Reference photos of the Keyless Work. One last thing to note with this movement. The setting lever is riveted into the Main Plate, so it's not able to be removed. Well this little gem is in the Watch Cleaner, and I've got a few weekend chores to do, so I'll put it back together tonight and post the results later. Hope you enjoyed this write-up, and got a few giggles out of it as well :)