Here is a list of all the postings Dick H has made in our forums. Click on a thread name to jump to the thread.
|Thread: Building a Congreve clock.|
Many thanks for the replies, I was looking for a project for the winter. A Congreve clock now appears a bit ambitious. Any suggestions in the direction clocks or things that do absolutely nothing?
I was thinking in this direction **LINK** and thinking of a Jaeger LeCoutre Atmos clock.
I know, I think I was in Richmond in the early seventies.
I was born in the NE and went to school in the NW. We were up there either to see the aunts & uncles or to take my gran back to the NW. In any case I have a memory of a Congreve clock in a (corner) jeweller´s window on the edge of the market place. This was the first time I saw one of these clocks and long before I developed an interest in clocks.
Some time ago I obtained John Wilding's book on building a Congreve rolling ball clock. I know they are lousy timekeepers but ..
Jusr reading the book I'm struck by the size of the thing. Has anybody come across plans for a smaller version? Has anybody got experience of building one?
They seem to pop up in The Model Engineer in the past (1947!) but I haven't found any plans.
Any comments appreciated.
|Thread: Why do we never have great documentaries in the Uk that go into detail|
Many thanks for the link to "Der Letze seines Standes".
I know that BBC iPlayer is difficult to get work outside the UK but does this link work outside Germany?
It´s about a guy repairing tower/church clocks based in Rothenburg ob der Tauber.
Wiki has a list of some of the series (in German). some are available on YouTube and some direct from www.br.de (but as I said I´m not sure if you can get the latter outside DE). The locations range from Berlin to northern Italy and Vienna..
The series came from Bayern Alpha, now ARD-Alpha a documentary channel set up by Bavarian TV
|Thread: John Wilding 8 day Weight Driven Wall Clock|
Your drawing would appear to fit my understanding based on the second book, the collar/collet being glued to the arbour and transmitting power to the motion work via the friction spring. However in the first book it looks as if the arrangement is different. If you look at Steve Bensons photo earlier in this thread you can see a shadow of the friction spring the other way round!?.
I must say I´m a bit confused, I know how my clock works.
Having a think.
The layout of the clock in the second book is different from that in the first. In the second version the collet is steel and also takes the centre wheel, the layouts are very different.
I think in the first book the spring is just a push fit in the protruding bit of the collet. In the second version there is a square filed on the collet end and a corresponding hole in the spring.
The wings/arms of the spring act on the back side of the minute wheel as a friction drive for the motion work.
The collet is just glued / "loctited" in place.
Hope this makes things clearer.
I don´t know whether this helps but this is a side on view of the motion work on the clock as built according to the second book i.e. pinions instead of lantern pinions etc. The whole stack friction spring, minute wheel and pipe, hour bridge, and hour wheel floats on the centre arbour and is driven by the friction clutch that sits on a square that is filed in the steel collet that protrudes through the front plate. Attaching the hour bridge tensions the minute wheel against the friction spring. The minutes hand is held in place by a washer and a pin through the arbour at the end. A reverse wheel with a pinion translates and reduces the movement of the minute wheel to drive the hour wheel. In this version if you look at the clock from the front the reverse wheel stub sits at somewhere between 10 and 11 o´clock. The brass friction / bow spring is a critical bit, it is made springy by hammering and you have to adjust the tension, too slack and the hands aren´t driven and fall to the 6 o´clock position, too tight,nothing goes. The alignment of the wheels might involve the addition of a washer just to get the alignment right. The older version uses a small bridge to hold the arbour for the reverse wheel. The hour bridge´s position can be moved (big holes small screws) to centre the hour pipe.
My clock is a bit rough and some bits are going to be remade but it´s running.
Anybody know how to make a chapter ring which doesn´t involve too much sawing? My lathe won´t take anything bigger than 16-17 cim dia.
Hope this helps,
Thanks to everyone for the suggestions and comments.
I think the problem is with my bit tight depthing of the hour/reverse hour wheel in the motion work. Anyway it runs, sort of now, on the smaller weight without the pulley. I took everything apart, polished it and put back together.
Thanks for the input.
I am finally trying to get my version of this clock going. I followed the later (updated) book which puts the barrel off-centre and uses a guide roller to help the weight cord across the barrel. If I use a straight drop with the weight, it runs with a 5.lb weight, if I use the guide roller I need a bigger weight, if I put the weight pulley in nothing goes. Either I´ve no idea how to string this thing up or I´ve got some massive losses somewhere. How far do the pallets enter the escape wheel, is the geometry of the anchor wrong or have I friction losses?
It runs but should have more ummph.
Any help appreciated,
PS: The "cure mechanism of an anaerobic adhesive (or anaerobic sealant as they are often referred to) is triggered when it comes into contact with a metallic surface. This will cause the anaerobic adhesive to gel and cure. To facilitate full cure, the anaerobic adhesive needs to have exclusion of oxygen in combination with contact with a metal. With both these boxes ticked, the reactive molecules inside the liquid adhesive become activated which triggers the curing mechanism, causing the monomers to polymerise and create a solid". (From Permabond´s website).
As to the lower limit on storage, it could have any number of reasons. Moisture sensitivity, bits of the mix might crystallise out. etc.etc...
These adhesives are a mix of lower and higher molecular weight components which polymerise to make a crosslinked solid.
The material is described as a urethane methacrylate. This is probably also moisture sensitive (depends on how/if the molecule is "capped". In any case it described as "anaerobic", so putting it a bag in a fridge might restrict the amount of air it comes into contact with, i.e. it will start to cure. On the other hand it might attract moisture, also not good. As to the difference between 5 and 8°C, go out on a cold morning and see when you can see your breath condense in the air when you exhale. All of these data sheets from manufactures tend to the cautious.
What you say about "chemical reaction rate doubles for every 10 °C rise in temperature" (Arrenhius) is a rule of thumb, it depends on the activation energy of the reaction and whether it is endothermic or exothermic.
This stuff comes in a bottle designed to allow air in to stop it curing prematurely but perhaps keep moisture out. I´m not sure whether throwing the bottle in the drawer is better than sticking it in the fridge.
The viscosity in use shouldn´t be a problem, its just the shelf life and storage.
In any case most methacrylates depolymerise if heated to ~150°C, so the polymethacrylate bit can be softened and will decompose with gentle heating (work in an open, well ventilated area ).
A couple of points:-
Loctite 638 is an anaerobic adhesive, i.e. it cures when you exclude air (oxygen).
According to the data sheet (**LINK**) the best temperature to store this stuff is 8-21°C.
i.e in a bag in a fridge might not be best.
Sorry I´m a chemist.
|Thread: Hi from Germany.|
Hi I´ve been subscribing to Model Engineers´ Workshop for a year or so now. I browse the forums for tips from time to time. I´m finally,after 8 years, ( I found the bill for the brass), trying to finish an Eight Day Wall Clock from a book by John Wilding. Up to now I´ve just lurked on the forums.
|Thread: John Wilding 8 day Weight Driven Wall Clock|
I assume you are working from the older book for building the clock. I started with this and then switched to the newer version.
Just looking at the old (red dust-cover) book the information you seek is scattered all over the place.
1) the arbor which supports the pallets and crutch is 3/32" (~2.4 mm), this matches the hole drilled when making the pallets (p.37, left hand column line 13).The escape and pallet pivots are 0.050" in dia. (p.29, Fig 42. bottom right). The newer book uses 1/16" pivots.
2) The back cock. The older book uses a back cock made of bits of brass silver soldered together, in the newer, a brass plate is supported by two pillars. I would take the drawing a p.42 Fig 68 as being a scale diagram (approx 75%). The holes back plate are drilled and tapped to suit the position of the back cock sitting on the pivot protruding through an arbor sized hole in the back-plate, even then there will be a little bit of potential movement, so it is suggested to add locating pins as well. This is before cutting out the upside down keyhole shaped hole in the backplate to accommodate the adjustable collet.
3) The crutch can be made out of one piece of brass and bent (the newer book uses 1/16" mild steel strip) or made from two pieces and soldered together (p.44). the top of the crutch has a central hole to sit on the arbor and is then held by two small screws ( approx. M 1.6-1.8 metric) to the adjustable collet. The two 10 BA holes in the foot of the crutch are to hold small plate to narrow and adjust clearance between the crutch and the lower brass block on the suspension spring, this is difficult to see in Fig 79 on p.45, and it is also visible in Fig 2 on p.5, once you have an idea what to look for. The crutch I made is simple steel with a slot. Hope this helps.
Living abroad my clock is a wild mixture of imperial and metric. The older book uses lantern pinions, the newer steel pinions. Having sat down to cross read the two, I see there are lots of differences.
Hope this helps.
Hi, I´m also building this clock. I have yet to summon the courage to pour the lead for the pendulum but the clock is ticking away in the cellar with a temporary light pendulum.
There are two "cookbook"s by John Wilding for building this clock .They differ in a few details associated with the mounting of the reverse wheel etc. and the newer book (a spiral bound type assembly of the original magazine articles) adds variations on where to place the barrel so a chime and date work can be added later. This can be confusing.
To get the clock running a little application of light clock oil worked wonders.
As to polishing the pivots, don´t look too closely!
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