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Thread: TD Clock Restoration
Posted 14 September 2017 at 05:09:48 UK time
P Hehir, New South Wales, Australia

I've checked the threads in the archive on the TD clock & gained some useful info. The location of the feed, colour & gauge of wire, the push method to trigger the clock plus also confirmed that there is no mention of the clock in the original wiring diagrams. However the method of earthing the clock was not mentioned anywhere, which leads me to ask the question. There may have been a black wire attached to one of the screws at the rear of the clock or the earth may have been via the tacho drive cable. Obviously there has to be a path to earth as the instrument sits in the wooden dash & as such is electrically isolated, except of course for the tacho cable which is earthed at the genny via the block.

Also as a confirmed DIY type can anybody provide details, hints, tips on maintenance & also of a simple & reversible mod to improve performance of the original clock? Diodes & transistors were mentioned in the archive but no detail on 'how to'. I'm unwilling to send my clock anywhere overseas as I've lost items this way in the past & original TD clocks are almost impossible to replace. Besides I'd much rather do it myself. Cheers
Peter TD 5801

Posted 14 September 2017 at 09:13:05 UK time
Dave Hill, St Neots, UK

See clocks4classics.com and buy the kit.
Dave H

Posted 14 September 2017 at 09:36:57 UK time
Declan Burns, Düsseldorf Germany, declan_burns@web.de

There is a replacement battery run clock and replacement dials available and it looks pretty good-not cheap though.
Regards
Declan

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Posted 14 September 2017 at 10:24:25 UK time
Tim Wilkinson, St Albans, UK

Peter

The Clocks 4 Classics kit seems your best bet for a close-to-original solution. The major advantage is that it eliminates the whisker contact which remains a potential flaw in the transistor modification.

I built a transistor mod some years ago so I can help with circuit details if you do opt for that solution.

The natural route for an earth wire would be from one of the mounting screws to an earthing point provided by the dash harness.

Tim
TD1580

Posted 14 September 2017 at 10:40:34 UK time
Bud Krueger, Marietta GA USA, budkrueger@comcast.net

Peter, see http://www.ttalk.info/TDWiringDiagrams.htm and note that the tachometer has its own black ground wire. That provides the ground for the clock. The path is from terminal E of the regulator to the instrument panel to the tachometer.
Hal Kramer wrote an article in the June, 1991 TSO giving detailed directions for transistorizing the clock. I had him do mine and it's still going fine. Bud

Posted 14 September 2017 at 19:36:09 UK time
LC Laurent31, France

One may ask what is "to improve performance of the clock" ?
A minute will always be a minute.

No electronic in mine (this is my job yet). I managed to clean the contact, bend it. Cleaned every gear with the help of a magnifier.
The coil was open. I reeled off the wire until the open circuit was visible, solder and reeled it on. Took a week but it is now a great pleasure to hear it ticking whith the original mechanism.

About reliability ? I've got a battery cut-off switch. My clock is off most of the time and it is on when I drive. It will probably last for years.


Laurent.



Posted 14 September 2017 at 20:02:38 UK time
Dave Hill, St Neots, UK

Actually it is about reliability. Not everyone uses a cut-off switch, and some people do use their T types quite a lot. The clocks4classics conversion retain almost all of the original mechanism and still ticks
Dave H

Posted 17 September 2017 at 18:31:23 UK time
W_Mueller, Germany

A watchmaker told me that idle clocks will run in problems that running watches will not have.

Posted 17 September 2017 at 19:14:47 UK time
LC Laurent31, France

That's probably correct for dust, grit. But the main problem with our clock is the little spark that gnaw the contact each second. You can see that spark in darkness. I can't make up my mind for running or idling the clock...
To cope with the spark, I added a free wheel diode in parallel with the coil.

Laurent.


Posted 19 September 2017 at 10:45:53 UK time
P Hehir, New South Wales, Australia

My hard drive rolled over & died not long after posting this thread & I've only just now got my computer back. I'll need time to digest the info above & I'll then respond. The clock is now sitting on the bench & when connected to a 12 V battery it runs for a few seconds & then seems to jam on the whisker. I'd love to try & clean the whisker but it appears to be incredibly delicate. Be really great to see some pics & sketches of the clock & a brief rundown on how it works. I figure I'll need a 10 power eyeglass to even see what the issue is. The fact that it does tick is reassuring & suggests that a good clean may solve the problem. Thanks for responding. Gotter love the T Type fraternity, especially those who use this site! Cheers
Peter TD 5801

Posted 19 September 2017 at 11:27:00 UK time
J Scragg, France

Peter,

Copy paste from the archives.

John



Posted 16 February 2016 at 19:56:38 UK time
J Scragg, France
Bela,

I used this document to repair my clock, it is the best that I could find at the time. It contains a diagram of the complete electric circuit.

http://www.sa.hillman.org.au/TT_SmithsClock.htm

There may be others, if you want to search for them, try using the key words: "smiths pin car clock repair".

John

52 TD

Posted 19 September 2017 at 14:34:03 UK time
P Hehir, New South Wales, Australia

Laurent as Dave says it's about reliability. By this I mean to simply attempt to ensure a reasonable degree of reliability & functionality. Not interested in 'altering time' (except to adjust the clock once I get it running so that it is reasonably accurate).

Declan I can't change the clock for one that doesn't look correct, so I'm keen to get mine up & running.

Bud I see the earth on both the tacho & speedo on Dave's diagrams. Neither instrument was earthed on mine so I'll add both to the earth circuit.

Checked out both articles John & it seems the likely culprit is carbonisation of the offset & contact pins. (Glad I took the precaution of wiring up the battery with + earth to the case else I would have fried the 'rectifier bridge and other items rendering the clock inoperative'.) Nothing though on cleaning the balance wheel assembly, including the 'whisker'. I'll examine these components tomorrow using the best magnification I can find. I'll also try & take some close up pics & post them here. Cheers
Peter TD 5801

Posted 19 September 2017 at 16:21:16 UK time
Bud Krueger, Marietta GA USA, budkrueger@comcast.net

Peter, the tachometer and speedometer cables will also provide a path to ground. Adequate for the lamps, but questionable for the clock's well-being. Bud

Posted 19 September 2017 at 16:48:42 UK time
J Scragg, France

Peter,

Copy paste from the archives (again)



John Scragg, Antibes France, john dot scragg at wanadoo dot fr

This may or may not help, but just thought I’ll let you know how I got my clock to work.

I cleaned the contact tip, cleaned and oiled the movement, tested it on the bench, powered by the battery charger, ran fine for days. Put in the car, Nothing! back on the bench ran fine.

I supposed that it was a voltage drop problem, I changed the feed wire to a larger diameter and placed star washers under the two clock fixing screws and the speedometer earth wire.

It has been running now for 4 years.


John

52 TD

Posted 19 September 2017 at 20:55:54 UK time
Rod Jones, S W Florida USA

Both Greg Howell and I have the Clocks4clasics electronic fix in our TD clocks and so far No problems encountered. Clock looks the same as original and works just fine. They have good videos and instructions on what to do to clean and install the required PCB and decal. Only use clock oil and not too much at that. Been several months now and running like a champ.
Rod

Posted 21 September 2017 at 22:44:59 UK time
P Hehir, New South Wales, Australia

A couple of emails offline suggested a mechanical clean. While still assembled I carefully scraped away at the balance wheel pin & retested. Last evening she ran for 3 hours before stopping. I'll have another go at cleaning off the carbon today. Yet to take any pics. Cheers
Peter TD 5801

Posted 22 September 2017 at 18:54:31 UK time
P Hehir, New South Wales, Australia

It seems a combination of the clean & the addition of some surgical spirit to the top bearing on the balance wheel shaft has done the trick. I have the still assembled mechanism supported face down so that I could easily apply a drop of the surgical spirit to the shaft bearing & she's been running non stop for 16 hours now & counting!

On the first couple of attempts after cleaning the contacts, the balance wheel would bind in exactly the same position suggesting that one or both of the bearings needed cleaning. I'll leave it run for another 8 hours or so then with the clock inverted I'll also treat the more difficult to reach bottom bearing. The idea being that gravity will assist the surgical spirit in cleaning out the bearing while the mechanism is operating. The spirit contains a small percentage of castor oil. I've also applied a drop to each end of the worm drive. I intend to repeat the procedure with the clock in both of the horizontal positions - the normal orientation as well as upside down with 6 o'clock at the top - applying a tiny drop to any bearings I can easily reach. Not sure whether to apply clock oil as well or just rely on the castor oil in the surgical spirit? Looks promising though. Thanks to John S & John CF. Cheers
Peter TD 5801

Posted 23 September 2017 at 20:05:47 UK time
LC Laurent31, France

Not too much oil. Only on the balance wheel bearing.
Just dip a needle eye in very thin oil and touch the bearing with the needle eye.

I bout this especially to fix my clock.
http://www.ebay.fr/itm/Lunettes-loupes-dhorloger-a-leds-eclairantes-bijoutier-bijouterie-de-precision-/142109395156?hash=item21166148d4:g:GNAAAOSwzgRWzKY9
Really worth it.

Laurent.

Posted 24 September 2017 at 11:25:53 UK time
P Hehir, New South Wales, Australia

Interesting test results. The clock functioned perfectly running for over 24 hours in the vertical position, both with the face up & face down. However when placed horizontally it would only run for a matter of seconds. After studying this for some time I became aware that the transverse escape assembly appeared to have a considerable degree of end play which I estimated at about .060". This appeared to cause the mechanism to jam almost immediately. One of the posts seemed to be bent slightly which I carefully straightened, reducing the end play of the transverse shaft to about .015". I again tried the clock in the horizontal position & she now appears to be operating normally. (Obviously when vertical, gravity ensured that the transverse escape assembly remained engaged with its escape gear). I also applied methylated spirits to the bearings I could reach to remove any traces of the castor oil from the surgical spirit, thinking that may have added to the problem.

Couple of odd things though. Although the hands move & keep reasonable time there is no audible ticking. Also there is a whisker mounted on the side of the mechanism dangling down towards the balance wheel but not making contact with anything. This seems to have no purpose whatsoever. This whisker is visible on the left of the pic, which shows the clock in operation, hence the blur below the balance wheel. Cheers
Peter TD 5801

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