Member postings for Roger Jelbert

Jubilee clock is now reserved.. R

It's great to see that enginners are still experimenting with the idea of making a "free pendulum" clock using modern electronics. My two clocks are still going well after about 6 years and I find the best way to live with them is to ignore the day to day variations in seconds. I decided that unless perfect correction for temp, pressure, humidity and even perhaps gravity (tides !) is incorporated once a well built clock is regulated as best as is possible it will average out to be a good timekeeper. A friend who has kept records of the going of a Synchronome clock by computer comparison with NTC reckons he can see the changes through the seasons of the year. It seems to me pressure variations are the greatest issue.
On the question of Post Office clocks, although the exchanges are (were?) powered by 50v batteries only the contact making circuits were connected directly from that voltage (50v relays and series loop clock circuits). The circuit for driving the Hipp controlled drive magnet were electrically separate in the clocks and were fed from 50v via a high value resistance. The drive EMs of a PO clock are about 9ohms and will work happily from 4.5 volts.

My interest in clocks electrial clocks has waned. Austin7's now largely figure. A few years ago I aquired the main works of the Jubille clock. In a burst of entheusiasm I made a case and bought (eBay) what appears to be an engineer made 30 second stepper movement. But now I want to sell this (and others in my collection) I'b be looking for around £50 for it. message me for details, photos etc. I'm near Penzance and won't post it but will keep until the summer if anyone is planning a trip down this way Roger

Thank you Vic..

In fact, I phoned, then drove pover to a model making mate who had a 8 x 1 tap and tapped a short legth of silver steel. Job done..Spur gear now fitted to the Toyota windscreen motor..Now I don't think I'll ever forget that there is more than one pitch for Metric Fine..Thanks you.

Thanks for that old mart...I'm stuck in the world of metric Coarse and thought Metric fine was 0.75mm pitch anyway..But a quick search soon showed me that other option...That must be the answer..Thanks again..Another adapter will be ordered immediately..Roger

Re previous...The adapters I bought were 5/16 x 24 UNF...I can no longer work out how to add photos..Still thinking about that !.

Hi..I've posted in this section because I think I will always be a beginner in spite of dabbling for years..I'm slowly making a coil (solenoid) winding rig to make a neat replaceplacent for a Syncronome master clock.
It makes use of several bits from the scrap/junk box and includes a motor from a 12v motor apparently from a Toyota.
My problem is the thread on the spindle which I jumped to the conclusion looked like 8mm metric. It wasn't - an M8 nut won't even start.
I used a thread gauge but as there is only 6mm worth of thread, 24tpi seemed a fit so I ordered a "ready to weld" threaded adapter to turn down to make a spindle for my spur gear. It arrived but that also only went down half way. I tried the other end which went 5mm down befor jamming...I thought maybe the thread machining wasn't to good so ordered another from a different supplier, but that also won't go down more than about 3mm before jamming..
The thread gauge may in fact be telling me it's 25 tpi (or 1mm pitch?) and the OD of the cut thread crests is close to 7.86mm.
So..What thread can this be ? Any help greatly appreciated..Roger (Cornwall)

Michael..
Thanks for the light hearted reply I wasn't sure if it was an acceptable post,,,or exactly where to post it..If everyone pushed their eBay listings to the forum things would become messy..
However, the A frame casting is now a rare item - I search ebay frequently for "synchronome" and I've never seen one come up..There' are probably only a couple of people in the country that would be interested anyway and to them this might be manna from heaven !
I spent far too much on the lot I bought that included it, just to get a case for a Gensign (Magneta) master clock refurb and the sale of this even at the starting price will help put things in a better light..
No further clues coming ... Roger

yes...Obvious when you know how ! I just didn't notice that..Thanks

Thank you to moderator JasonB for fixing the link..
@ Emgee: There doesn't seem to be a way o f withdrawing"/deleting an old one either. nI fact, is it not a bit odd that the format of the classifieds is different from the general forum posts where an "edit" button shows in the tile bar and you can link (as I now know!) to an album.
@Michael - the cHipp toggle clock is still running perfectly and plans for a new, tidier, version are formulating..In the eBay purchase I recntly made I got a spare Gensign chassis, drive magnets and pendulum rod (like GPO 36 clock) and intend using them as the basis..Sadly I'm still not much of a mechanic
Rogerj.co.uk

I recently posted an item in Classified (unfinished clock) and made a mistake in the web link (I omitted .htm at the end of the address) I'm getting emails telling me the link doesn't work but I can't find any way to edit the posting to correct it..Is it possible ?

Thanks for those picture instructions. Sorry I didn't find them myself.
No one seems to have recognised the design the constructor was using but maybe they were published somewhere else. I'm putting them in the classified section for a tenner in case anyone fancies finishing it..

Thank you Robbo for adding that working link..I'm afraid I just couldn't work out how to add an image using the two available options..For dum dums like me a walk thru "sticky" on posting images would be brilliant

I've recently bought an electrical master clock from an eBay seller. It came bundled with a box of misc parts, some of which appears to be the start of a project. Not all of the parts may be associated with the build but the escape wheel and anchor look likely parts. I've put together some bits that seem to fit. The frame stands 7" high.
Pictures here on an external link:
http://www.rogerj.co.uk/clock project.htm

In the stuff I inherited from my father was a pair of v blocks with no clamps. I occasionally search e\bay fro replacements but never found any - until I came close today...but they are the wrong size. And I don't quite get the way the sizes are quoted.
Mine are L=50.11mm, H=34.83mm, W=44.18..Any ideas on a pair of source of suitable clamps would be welcome !

I remarked on the ball bearing pendulum suspension in the example I have.
Westbury deals with that topic in his original article, mentioniing the alternatives to springs that have been tried. He comes down in favour of the conventional spring - and copied his from the Synchronome. My clock builder seems to like them as he has used several where clock makers would use pinions.

The Jubilee clock was reviseted again in 1965 by H.H.Knie who picks up on a subject dear to Hope-Jones - positive contact making. He reckons the original Hipp Toggle trailer is a superior system. Anyone who has seen a PO No36 clock working could not but agree. The action is so snappy and positive.

I had assumed that the upcoming new electo-mechanical escapement mentioned by Michael was to appear in ME. I don't see the Horological Journal so maybe won't see that after all.

Thanks for all the input....I have enough food for thought on how to make use of the parts I've got..Roger.

That sounds intriguing..I'm in no rush and can finish the case I've been working on..

I've read the articles and see that the impulse method is an improvement suggested by Wilding at a later date. I won't be building the ME clock but will use the chassis and pendulum in some new form..Possibly in the forthcoming "game changing" way" if the mechanical construction methods are within my ability. Otherwise it will be entirely electrical as the one I've already made...Roger

Thanks for those replies. Fancy the answer being right here in the ME archives !.

I am about to print out the articles linked to by Jason to see how my example .compares. Will reply again when I've done it.

If impulsing like that ever worked it must have been very tricky to set up.. I agree with Michael...HJ would indeed be turning in his grave. Several features smack of reinventing the wheel...A ball race in place of a suspension spring being another..

I have five Synchronomes so I knew it wasn't one of them !...Roger

This is my first post ! I have been given a part built clock that can either be canabalised as a basis for a new clock or perhaps finished as it was intended if I can get some more details of it. The clock was given to me by someone who in turn had aquired it from the estate of a model engineer. It is incomplete.

I'm wondering if anyone recognises the design ? Of course it may be an original design by the maker..The gathering arm (4) is short and places a significant drag on the pendulum.
The Hipp toggle is a version invented (according to F Hope-Jones) by Herbert Scott of Bradford. The count wheel (3) has small secondary notches on the crest of the teeth into which the gathering arm (4) drops when the arc has fallen sufficiently. there is no sign of a contact assemble present.

The impulse arm (1) is a puzzle as it seems very light to be a gravity arm. I can only guess it was supposed to connect with the lower face of the pallet (2) upwards, under the direct force of the electro magnet.

Any thoughts ?

Edited By Roger Jelbert on 03/11/2016 12:53:31

Edited By Roger Jelbert on 03/11/2016 12:55:17