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Showing content with the highest reputation on 02/10/19 in all areas

  1. Thought it may be worth to share; I received a pretty beaten up, none-running 1890-1900 cylinder-escapement pocket-watch. It had all sorts of problems, a list too long to go into details. Among those problems was a bend/broken minute hand. It inevitably broke off when trying to straighten it. The center-hole diameter of the minute-hand was 0.5mm and the length was 15mm. The hour-hand had a hole diameter of 2.0mm and the length was 10mm. Searching the internet to find an identical set proofed futile. The watch is a heirloom so originality was a priority. The hands turned out the be made of bronze, a copper-tin alloy. Therefor it made sense to attempt soldering but the part that had to be soldered had a thickness of only 0.3mm. Both parts had to be fixed in place with a sort of clamp capable to fixing both parts, being heat resistant and "none-sticking". A soldering iron, even with the smallest tip, would be far too big for the job and to avoid touching the parts, I choose to use a hot-air gun used in electronics for soldering SMD-components to a circuit-board. A few test were made which tin to use and at which temperatures. 300 degrees C with tin used in electronics seemed to work fast and made the tin to flow nicely. I used a soldering flux-paste. The clamp consisted of two metal rails, slightly diverting from each other to give many clamping options, bolted on a plate of gypsum. Pulling over a #1000 grid sand paper, I made two 45 degrees chamfered edges on either end of both parts; The two parts were clamped in; Applied some soldering flux, heated it all up to 300 deg.C and applied a tiny bit of tin. Once cooled down, I removed some excess tin with a small diamond file. Here a picture of the back side of the minute-hand; And here the front; the tin didn't flow further away from the soldered joint or around the edges Most likely not the strongest repair in the world, but when not touched it should be strong enough to do the job. On the picture the hand color looks black, but that's due to the lighting. In reality the hand hasn't lost any of its shiny patina at the front ...... Anyway, I thought to share this repair as one of the many different possibilities
    3 points
  2. You da’real mvp! (I’m English so I probably have the context all wrong but thought it better than typing “Good show old bean!”) Sent from my iPhone using Tapatalk
    1 point
  3. So I had a quick look and with a lathe and some blue steel rods at about 1mm, it is possible to replace the stud on a spring winder.I think you just punch out the old one and then grave the small piece of 1mm blues steel down to size with i minor 3 deg taper, then tap it into the opening. Easy Peasy Sent from my iPhone using Tapatalk Pro
    1 point
  4. I recently decided to attempt to create a video of the disassembly of a Chinese clone of the ETA 7750. In actuality it is a variation of the 7750 platform. The movement does not have an hour recording feature, but instead has a continuous seconds hand in the 6 o'clock position. I also show where the clone design improves upon ETA - namely protection from breaking the date indicator driving wheel if the user attempts to set the date using the rapid corrector during the "forbidden" time range (10pm-2am??) Certainly not anything near the quality of Mark's videos, but I decided to give it a shot! Assembly video will be posted when available. Enjoy.
    1 point
  5. Thank you. I had found that in my grandfather’s Bestfit encyclopedia. He actually had it marked (about 11 rows up from the bottom). Sent from my iPhone using Tapatalk
    1 point
  6. Nice. Let me share a little tip. Solder paste. Specifically "Mechanic" branded Chinese solder paste from ebay. This stuff is used for SMD soldering, particularly small runs and SMD rework, and comes in leaded and unleaded. I would suggest the leaded version is better, as it is easier to use, but obviously, don't go eating it, and wash your hands after use. https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=mechanic+solder+paste&_sop=15 If you buy from ebay, make sure you are buying the solder paste, and not just the flux with the same brand name. The paste has a built in flux, and consists of micro-beads of solder. The advantage of using this, over solder wire, is that you can be very precise, in the amount you use, and the location you put it in. It makes soldering tiny electronic components much simpler, and would probably have been ideal for this job.
    1 point
  7. You can kill it or cure it with electrical spray contact cleaner.spray it into the gears flush out the gunk.let it dry completely.slightest bit of oil on the shaft holes.make sure the cleaner is plastic safe.forget taking the movement apart.
    1 point
  8. Nice technique. You thought outside the cylinder and it looks like you had great success. Fine job. Thanks for sharing. Cheers.
    1 point
  9. The bezel doesn't need to be removed to replace the crystal. You will however have to remove the movement since the glass will need to be pushed from inside the case to remove it. And ideally with a suitable crystal press tool. Since pictures can speak a thousand words I've done a quick search on YouTube for you and https://www.youtube.com/watch?v=T0Zqit4r0wM seems as good a video as any. If you're new at this it might be worth watching the whole video but at approximately minute 8 to 9 is the action shot relating to what you need to do. Hope this helps.
    1 point
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