Jump to content

AndyHull

Advanced Member
  • Content Count

    2,527
  • Joined

  • Last visited

  • Days Won

    67

Posts posted by AndyHull

  1. The coil from @JohnD arrived in the post and set about modifying the metalwork to allow it to squeeze in place of the original. An hour or so of careful filing and Dremel work and it now fits like a glove.

    I also took care to ensure that the new wiring is double insulated with a few patches of Kapton tape, a nylon bushing to replace one of the original brass nuts and some heat shrink sleeving ensuring that there is little chance of this ancient synchronous motor giving anyone a shock, even if the thing is dropped or the wires are pulled. I can't remember where I got the strange dayglo green cable ties from, but since nobody will see them, who cares about the colour.

    It got a good clean while it was apart as unsurprisingly it was filthy. The worm gears both had a thick pasty gunge on them that probably started life as either grease or oil. All of the bras surfaces were sticky and nasty.  

    Surprisingly it worked first time. After gingerly flicking the brass starter on the rear I let it run for about 10 minutes to see if it would overheat, but it was fine. No shocks, no smoke, no nasty electrical skid marks, no scary surprises.

    I then stripped it all down again and gave everything one more clean to ensure that I had removed all of the dust and filings from the modification and rebuilt it again gave it a proper oiling. This time though when I flicked it into life, it started to click ominously.

    My initial fear that the insulation might be breaking down and the coil arcing were unfunded, I has simply misaligned one of the gears and it was jumping.

    With that remedied I buttoned it all back up again and it is now sitting in my explosion containment test stand (the fire hearth) and whirring away with a low but pleasing hum.

    The patented tick also works. If you look carefully in the pictures of the mechanism you can see that it consists of a small steel blade that rides over some serrations on a brass wheel. Each time it falls off a tooth on the wheel, it clicks.

    The teeth are arranged to it ticks about twice per second. I've switched this off for the time being so I can listen out for any other strange noises it might produce.

    If testing goes well, then I'll case it back up and let it run, so I can see if it keeps good time.

    After that comes the tricky bit. Making a replacement for that wooden decorative trim.

    Here are some pictures of my test fitting of the coil, showing the modified brass top plate, the plastic spacer and some close up shots of the gearing.

     

    RIMG0302.JPG

    RIMG0304.JPG

    RIMG0305.JPG

    RIMG0306.JPG

    RIMG0307.JPG

    RIMG0308.JPG

    RIMG0309.JPG

    RIMG0310.JPG

    RIMG0311.JPG

    RIMG0312.JPG

    RIMG0313.JPG

    RIMG0314.JPG

    RIMG0315.JPG

    RIMG0316.JPG

    RIMG0317.JPG

    RIMG0318.JPG

    RIMG0319.JPG

  2. 6 hours ago, jdm said:
    11 hours ago, AndyHull said:

    ...

    Petroleoum ether is sold on Ebay, so not difficult to get.

    Indeed, however not everybody lives in a country where ebay or Amazon operates, or where suppliers will ship to, or at least ship to at a realistic price, so for those readers, you may need to substitute one of the above suggestions.

  3. On 1/18/2021 at 4:31 PM, jdm said:

    If you had ordered petroleum ether you would have got a proper horological product, and spent less. Lighter fluid is made to burn not to clean, and is not recommended by any manufacturer, professional school, etc.

    Indeed, however if you can't get hold of "petroleum ether" lighter fluid is a reasonable substitute.
    If you are doing things professionally I would stick to quality products, but for the hobbyist, lighter fluid works.

    You could also use "white gas" Coleman stove fuel or similar.

    https://en.wikipedia.org/wiki/Petroleum_ether
    https://en.wikipedia.org/wiki/Naphtha
     

     

    • Like 1
  4. 4 minutes ago, JohnD said:

    I'd be tempted to file the two sides of the top plate Andy........

    I'm tempted too, since I've nothing to loose. Let me sleep on it, I still haven't entirely given up on the idea of unwinding and re-winding the existing coil. I suspect that wont work, but I'll look at it tomorrow.

    Would there be any possibility of filing some notches in the coil you have, or is there not enough "spare" plastic?

  5. 1 hour ago, JohnD said:

    Hi Andy, overall length of the plastic former is 29.89mm, width 18mm x 19.6mm, with 17.5mm x 20mm over the thickest part of the coil windings. The rectangular slot through the former is nominally 8mm x 6.5mm

    Nope. Just too tight. The maximum that you could squeeze in is 28.34mm without filing the plates Close, but no cigar. 🥴


    The other dimensions would not be a problem, but unless I could loose 1.5mm over the length, then it wouldn't work.

    Here are a couple of additional pictures, showing the rest of the mech. and the coil gap.

     

    RIMG0298.JPG

    RIMG0299.JPG

    RIMG0300.JPG

    RIMG0301.JPG

  6. 3 minutes ago, JohnD said:

    Hi Andy, overall length of the plastic former is 29.89mm, width 18mm x 19.6mm, with 17.5mm x 20mm over the thickest part of the coil windings. The rectangular slot through the former is nominally 8mm x 6.5mm

    Let me check if that might just squeeze in to the space.

  7. 56 minutes ago, JohnD said:

    For a second or two I thought that you were going to be in luck Andy, as that looked identical to two of my unidentified coils, but on measuring one of them I find that it was just under a couple of millimetres bigger all round...😪. If it is any use though, I measured the DC resistance of the coil and it was 6.1K ohms....

    What are the dimensions of the ones you have?

    If the iron core would fit through the hole, and the coil would squeeze between the ends of the plate, it might just work.


    6.1K sounds about right, I was going to guess about 10K Ohms as coils on similar items (washing machine solenoid valves for example) draw about 24ma consuming about 5W roughly, which means the coil DC resistance is probably of the order of 10K.

     

    image.png.85739b446ba0e44a63845fc993d347dc.png

    I might explore using one of these, if I have a scrap one lying about, either as is, or winding its turns on to the metamec former.

  8. 18 hours ago, JohnD said:

    What does the coil look like Andy?

    A good question. It looks like trouble. 😋

    RIMG0279.thumb.JPG.3eb9f41d490ddda8931d912179a0d6d9.JPG

    I pulled the coil out and unpeeled the top layer to see whether I could simply resolder the feed wires to the coil, but as you can see, despite my best efforts this was not successful. Initially I was hopeful, as the original feed wire had broken from the tab due to corrosion caused by the ancient rubber insulation decomposing and absorbing moisture. The problem is though, that this corrosion may also have affected the inaccessible inner feed wire.  It appears therefore that the break lies either on the bottom attachment (which would necessitate unwinding the entire coil) or it lies somewhere in the middle.

    I've attached some pictures of the mechanism and my failed attempts to fix the coil. The dimensions of the coil are in the sketch in the last picture. You can see from these images that the dimensions of the coil are fairly precise as it just manages to squeeze in to the space. Since I don't have any idea what the original resistance was, I'm a little reluctant to attempt to wind the coil with fresh wire (which I could probably do using the seweing machine), since getting this wrong runs the risk of winding a coil that runs hot which might be a little exciting,  or one that has insufficient oomph to turn the motor.

    I guess I could un-spool a meter of the wire and measure its gauge and resistance, then simply count the number of turns on the coil, but frankly that does sound like a lot of work. By the same token I'd rather get it working with the original mechanism than take the easy route and fit a quartz mech.

    I've put the mechanism back together for the time being, to ensure that I don't loose anything,  while I ponder what I'm going to do next.

    RIMG0284.thumb.JPG.56e54a42f5e00b4fa913660b4c670af6.JPG

    Wrapping the enamel wire on to the new feed wire. The core copper wire is approximately 0.04 mm in diameter, or roughly half the thickness of an average human hair. 46 awg wire for comparison is 0.039mm in diameter, so I think it would be safe to conclude this is 46 awg. However your guess is as good as mine regarding the number of turns on that coil.

    RIMG0285.thumb.JPG.c43d65d6e00113a92323071fab1025a2.JPGRIMG0286.thumb.JPG.f3e695a81fff09e5c90026a8f2070887.JPG

    Soldering the enamelled wire on to a replacement feed wire. 

    RIMG0287.thumb.JPG.2fdb3637184aebf43a64bc05c828cc23.JPG

    The rear of the front plate showing some of the gears.

    RIMG0289.thumb.JPG.61961ad0a0ba5f8cf632906a963ae32a.JPG

    The failed repair re-fitted to show the clearances.

    RIMG0291.thumb.JPG.ed370235083c773461018e7fb3c7c14b.JPG

    Those two pins at the bottom are where the feed wires would attach with tabs and the mains cable would attach from the outside.

    RIMG0292.thumb.JPG.901299aff5f93e8b73bb0910dbae0957.JPG

    The "bearing". I'm not sure what exactly this is made of, but it may be graphite. It is not an electrical contact and brush, as you might think. The only electrical part of the clock is the coil.  The motor needs to be spun in the correct direction following loss of power by a mechanical contrivance operated from the back of the case.

    RIMG0293.thumb.JPG.4d17ed00d0cbdda8ebd06dd3f02587fa.JPG

    The spring and bushing refitted. There is a similar bushing on the other end of the motor shaft which can be accessed using the wide brass grubscrew like widget on the rear of the case with the screw slot in it.

    RIMG0294.thumb.JPG.97c13c4b2a29f957e400e2b8f0c1e9a8.JPG

    That strange window lets you see if the motor is turning. Presumably this was used in the factory when testing.

    RIMG0295.thumb.JPG.0c4ddda9c4ab1355693844320aaf3112.JPG

    The "control panel". On the left the "kick start", followed by the adjuster for the hands and the "tick/silent" control.
    The bushing on this side is behind that wide brass screw. It looks exactly like the other one.

    RIMG0296.thumb.JPG.2820eb5a6b6b846ce7f5f8d29063c970.JPG

    The mains wires were originally fed in to the lower left and right holes and clamped in place by grub screws accessed from the top two holes. There was no earth. That middle hole in the bottom was for a cable clamp screw. The top two holes are therefore where you poke your screwdriver into the live terminals when the power is connected if you want to entertain your audience by connecting yourself accidentally to 240 V AC and blowing yourself across the room, with much foul language. Elf and Safety 1950s style.

    RIMG0297.thumb.JPG.ce044442877fdb327d3a9fed20c5a782.JPG

    The dimensions of the coil including the sizes of the hole for the iron core.


    There is a corner missing from the plastic former. This may have broken off, or may perhaps have been  removed in the manufacturing process to ensure the coil is orientated correctly while assembling.

    However since the motor is not self starting, and needs to be spun in the correct direction by that knob on the back every time the power is lost, I suspect the direction of the field is not important, so fitting the coil back to front probably wouldn't make any difference.

    RIMG0288.JPG

    RIMG0290.JPG

    • Like 1
  9. Metamec becomes radio active.

    RIMG0244.thumb.JPG.f0f8ab443ba6ea1e2c3ad192b85155ec.JPG

    The electric mechanism on the second Metamec has a blown coil, so while I figure out if I am willing to try stripping the motor down and repairing the coil (unlikely, but I may give it a bash), I thought I'd see if I had any quartz mechanism in case I need a plan B.

    After much rummaging through spares and a quick trawl through the junk in the attic I found what I was looking for. An "Atomic" (Radio controlled) quartz module with the correct reach to fit in place of the old workings.

    I fitted the radio quartz module to a piece of clear plastic sheet, cut to match the outline of the original module which allows me to re-use the original brass screws to centre it and avoid drilling any more holes in the woodwork.

    Naturally the original hands don't fit, and since they are what gives the thing the majority of its character I'm going to see if my 3d printer can produce something sufficiently similar to the originals to make it look the way the designer intended. 

    If that fails I guess I could attempt to etch some from brass sheet paint them the correct shade of off white.

    Until I get some traction with either the coil rewind or replacement hands, I've put replacing the missing piece of woodwork on hold.

    RIMG0276.thumb.JPG.08864c0789ae555d3e946c852d67433c.JPG

    So now I have an even less complete Metamec that is accurate to the second (but not the hour or minute). Nobody is perfect I guess but I'm willing to chalk that down as progress... of sorts.

  10. Reading about the Timex Hopalong Cassidy watch, sent me down a rabbit hole via Kelton watches, the French Timex arm to these articles, which you may find interesting.

    https://translate.google.com/translate?sl=fr&tl=en&u=https://fr.wikipedia.org/wiki/Histoire_de_l%27horlogerie_%C3%A0_Besan%C3%A7on

    https://nhujzchxszmfjwodqweptl7jha--fr-m-wikipedia-org.translate.goog/wiki/Lip

    https://nhujzchxszmfjwodqweptl7jha--fr-m-wikipedia-org.translate.goog/wiki/Revenu_(métallurgie)

    https://translate.google.com/translate?sl=fr&tl=en&u=https://fr.wikipedia.org/wiki/Histoire_de_l%27horlogerie_%C3%A0_Besan%C3%A7on

     

    Allow a few seconds for the translations to appear as initially they may show up in your browser in French. Depending on which browser you use, you may need to click through the "Translating.." link. Google translate has a few quirks.

     

  11. 7 hours ago, HectorLooi said:

    I discovered the reason for the loss of power in this watch. The teeth of the winding ratchet assembly are worn off to the point that it slips when the spring is wound to a certain tension

    Are you sure this is the cause?

    image.png.acde71f4baa414cb5ba87b06de8c238a.png


    I think if it looses power it is more likely to be the click spring. If this is badly worn, it will release or slip when the power in the mainspring increases.
    Does it manually wind without slipping? If not, the click is worn.

  12. One other thing to check. It is possible to fit the plate that holds the oscillating weight two different ways. In other words, the plate is not symmetrical.

    If you screw it on in the wrong position, then the pawls will be in the wrong position and the weight will not work correctly. I have done this a couple of times, however in my case the weight wouldn't turn correctly either when the movement was cased. If the case has more space though, then it might be possible to case the movement and still have the plate on back to front.

    Also check that the spring for the pawls is correctly fitted and the pawls turn the winder when you engage them manually. If not, then you will need to swap parts from a donor.

     

    image.png.f4c91a5b18c529bf1d5a514e1e78af14.png

    Also there is a manual available on line which explains how it all fits together much better than I have.
    I've attached it here in case you do not already have it. It also details where to oil.


     

    From memory, the pawls that drive the winding wheel should sit more like this picture. 

    109.pdf

    • Thanks 1
  13. You may be surprised to know that one of your watches is featured in the collection of the V&A museum.

    HopalongTimex.jpeg.d2caa6c8fdcce81605c74e54cbaf69bc.jpeg

    Source:- http://collections.vam.ac.uk/item/O1160743/hopalong-cassidy-watch-timex

    That's some pretty creative cardboard engineering going on there.

    The one in the V&A pictures is described as being located in the collection of the V&A Museum of Childhood.

    https://www.vam.ac.uk/info/transforming-the-va-museum-of-childhood


    This is presumably not directly related to the Museum of Childhood in Edinburgh which I visited many times when I was young.

    https://www.edinburghmuseums.org.uk/venue/museum-childhood

    https://duckduckgo.com/?q=Collection++Museum+of+Childhood&t=newext&atb=v124-1&ia=web&iaxm=places

    If you want a trip down memory lane, or have some youngsters to amuse and you happen to be near Edinburgh, this too  is well worth a visit.

    • Like 1
  14. image.thumb.png.5ca626ff1253cf776ba25c44143cc425.pngSadly this is missing its balance, dial, minute wheel, hands, bezel and glass.

    It should look like this example. 

    image.png.55c10a71d37166f356ef8824ddaea34c.png

    image.png.087d0960d2519bc85381739b2b3b344d.png

    (Image source https://www.catawiki.com/l/5306421-bulia-depose-old-clock-ca-1930 )

    Possibly a forlorn hope that I'll be able to make it run, but nothing ventured... Well actually £3.75 ventured, including postage, but at that price, I won't be crying in to my beer if it never runs.  

    The inverted dial and long stem suggests this was possibly from one of those new-fangled automobile thingies.
    It might even possibly be from a heavier than air flying machine!
    Does anybody remember travelling in one of those ;~) 

    • Like 1
  15. It seems "yon loons and quines fae Balmoral" had a soft spot for Metamec clocks. 

    ByAppointmentEnhanced.thumb.jpeg.1931fa5a3278518a09400b0d9e4d22af.jpeg

    Actually, come to think of it she spent more of her time at Scone, but that's neither here nor there. However the company was still producing some "Horological Products" of quality in 1990 it appears.

  16.  

    image.thumb.png.48872fb9c84727c16777f25883784e57.png

    Today, something a little different as a lunchtime project.

    RIMG0250.thumb.JPG.4994fa530118eee5861d23302c550ef9.JPG

    Not a watch, but somewhat similar in that is has hands and a hairspring.

    RIMG0253.thumb.JPG.74471eeef7867da3ff99257a09351dfb.JPG

    This is the mechanism from a Taylor "Stormguide" banjo style aneroid barometer and thermometer. Needless to say, owing to its condition when I purchased it, it also qualifies for the 404 club. 

    I have a couple of other barometers, one of which I've had for many years, which I fixed up as a kid, and another that we got as a wedding anniversary gift.

    This one has obviously been dropped. The shaft for the hand was bent, and the hand was damaged, with the collar missing.

    Straightening the shaft was a delicate operation, as I was sure it would snap, but with a little care it is now unbent.

    RIMG0257.thumb.JPG.686d40a55b1d0f66e8b6d22899de0385.JPG

    RIMG0258.thumb.JPG.7c44de092af39885efbb12400a027e21.JPG

    RIMG0259.thumb.JPG.08f5d95926a614f764c5f03570f4ec24.JPG

     

    With that taken care of, I fabricated a new collar from the straw from an air duster can, and glued it in place on the hand with a spot of GS cement.

    RIMG0260.thumb.JPG.7a8e980f8651b3506bd6cca60cf50e91.JPG

    RIMG0261.thumb.JPG.47553f462070655f1089d543a9e3ec1b.JPG

    Next the dial was re-fitted with some double sided tape. This isn't a very expensive mechanism as you can see. The better ones use screws or clips to hold things in place.

    RIMG0263.thumb.JPG.8388df4bbdeff3ed2dce44c9cd351136.JPG

    RIMG0264.thumb.JPG.1912dc0c95e432081ed91626f393f825.JPG

    RIMG0265.thumb.JPG.ab12e708a86b027398684cb079bb0498.JPG

    Finally I popped the hand back on, with another tiny drop of GS cement, and left things to set up with a cardboard shim to ensure the hand remained flat and parallel to the dial.

    RIMG0269.thumb.JPG.bf296e4086cbb70ab7a368d16051ac97.JPG

    The hand was set to match the reading from one of the other barometers, and now all that remained to do was check that it worked, pop the plexiglass back on, put it back in the "banjo" and hang it on the wall.

    • Like 1
  17. RIMG0242.thumb.JPG.9eee1a5dd4abb6d3cc77c16b5f8c4c58.JPG

    I stripped and cleaned the 1950s Metamec Electric clock today. It had been lying in "covid quarantine" since its arrival a few days back. 

    RIMG0243.thumb.JPG.daf2278dec1751c579eb9bfe7e052bd2.JPG

    As well as the missing wooden detail, it also has a slight fault. The original cable was held in place by two recessed grub screws and a cable clamp of some description. The clamp is missing as is one of the grub screws, which is not a huge issue as I can probably replace those with something modern relatively easily.

    However the second grub screw is stuck in place and its head has been stripped off, so I will need to figure out whether I want to try to extract it, or fill the holes and make some alternative arrangement to fit the mains flex. I'll probably go for the second option as it will be a lot more secure and less of an electrical safety risk. The idea of recessed live terminals is a little too 1950s for my liking.

    RIMG0246.thumb.JPG.b2fe91348919bc5297784477d149cfeb.JPG

    The more obvious chips and dings in the finish were touched up with shellac, which will probably need a couple of additional coats with a light sanding between them, and I still need to figure out what to do about the missing left hand wooden edge piece.

    Looking at the small remaining  broken piece of it that I have removed, my best guess is that it is oak, so I can either find a bit from the log pile, or maybe take a trip to B&Q and see if they have any hardwood mouldings that could be knocked in to shape and stained. The most tricky part I suspect is not going to be shaping the replacement piece, but colour matching it.

    • Like 3
  18. 6 hours ago, Poljot said:

    Who does not love Timex watches, eh?..

    Love 'em or hate 'em, you gotta admit, they are "interesing". 😋

    The manufacturing tolerances are not as fine as a quality mechanism, but that is part of their appeal from an engineering perspective.

    They do have some clever shortcuts in order to keep the price down. Furthermore despite their built to a price nature, they also seem to have passed the test of time remarkably well.

    I'm not sure the same can be said for some of the more modern offerings. Cheap quartz mechanisms tend to be a lot lest robust than clunky "clockwork toy" Timexes.

  19. image.png.02cd6aa920fe6dc0fa85b7d158231eb8.png

    Wot?! No backup.... Snifff....

    Been there.

    Lots.

    Many years ago I worked as a field engineer installing and maintaining multi user accounting systems.

    One customer had a flood, or to be more accurate a large part of Glasgow got flooded, so they had no computer, no backup tapes.

    The real killer though was that he bank vault in the bank at the other end of the street, where they stored their off site backup... was also flooded.

    Just goes to prove, you can never have too many backups. They eventually resorted to keying in all of their customer details from old reams of paper printouts (which shows how long ago this was). But first they had to dry out the printouts by hanging them across lots of string hung up in a big hallway in their temporary premises. Their insurer paid for new computer equipment which we installed, and for the cost of hiring a bunch of people to re-key all of the data they could. The computer was expensive, but the cost of the data entry probably twice that, and they still had to rely to some extent on some of their customers to tell them what they owed. 

  20. On 12/10/2018 at 9:25 AM, AndyHull said:

    When I get back from my holidays, I'll order up a crystal for it.

    RIMG0213.thumb.JPG.b75777580914059b7c9413b042ea5642.JPG

    Well I guess I forgot to order a crystal for it, partly because it has one of the most ravenous arm hair eating band I've ever encountered, which kind of spoils the fun of wearing it. The monster hair puller is the original Seiko steel strap I might add. 

    RIMG0217.thumb.JPG.0d4a852b21e655d4a252baca67c98dc4.JPG

    However it is a classic Sekio 5 design (from 1981), and it seems a waste to have it just sitting around unworn, so I put a leather strap on it and I'll measure the crystal this evening and order one... probably.. if I don't get distracted by something else. 

    Who knows, I might even have a crystal in stock, and be able to strike another ancient item from the todo list. 

    • Like 1
×
×
  • Create New...