Synchronome

Hi Chaps

Any one out there building a synchronome? I have just bought a backplate casting and am casting around for additional info. I have the Electrical Timekeeping (Hope-Jones) book and Electric clocks and Chimes. Could do with a source for swedish iron too if anyone has any bright ideas.

regards Martin

You do know there was a build series in ME about 20 years ago?

I think an old GPO relay can be used for the magnet core.

... or use the core material from a scrap transformer.

Russell.

Or slice up a body panel from a scrap Volvo or Saab

Hi Chaps

I have found the ME Jubilee Clock (Edgar Westbury) 1958 but no synchronome. Anyone have any other references to a series in ME ?.

Transformer cores are laminations of silicon steel. I need 1" bar stock. I can use mild if I have to or find some meaty solonoids but it's nice to get as close to the original design as possible.

I like the Volvo/Saab comment. Volvo's are closer to plate than sheet material.

regards Martin

.

Martin

You could try here

If you're lucky, it might qualify as an "Engineering Sample"

MichaelG.

Sorry, wrong magazine. Engineering in Minature, Jan 1987 to May 1988 "An Electric Master Clock" by Elliot Isaacs. The index sometimes leaves out the 'An'.

I assume the casting is the one from College Engineering

Hi Martin,

I restored a synchronome some 15 years ago. The coils were in rather bad state so I desided to replace them by new ones and keep the original coils in spare. I used normal BMS for the cores. There is some remanent magnetism but this does not any harm. You must set the end stops for the armature carefully to prevent metal to metal contact with the coil cores. Succes with your new project.

Kind regards, Johan.

A thin non-magnetic spacer such as thick paper can be useful to help prevent the sticking of the armature to the cores by providing a small gap in the magnetic circuit.

John

Last night I was going to write, I'll do it now, a small brass rivit in one of the faces that might touch will prevent the poles sticking. Ian S C

Hi Chaps

Thanks for the replies. I have acquired a chunk of swedish Iron curtesy of a friend. It's 3/4 plate so I intend to laminate two slices together to get the thickness. Probably soft solder together.

The casting is from CEng and is very good.

Point noted re stops and anti-stick tricks. I will try and get hold of the Eng in Min copies.

I may well make BMS cores too to make a comparative test, if I do I will post the findings.

Martin

Howdy,

I just finished my first assembly of a Synchronome clock based on the Engineering in Miniature build series written by Elliot Issacs.There were a couple of mistakes in the build series, dimensions for the roller support are incorrect, and drawings for the bearing plates for the gravity arm and the armature are missing. Other than those, the build went well, it takes a fair amount of hand adjustment to set the clock up to allow it to run easily, as the adjustment of the various parts to work together is critical. I used the CES backplate and Hope-Jones book "Electric Clocks and How To Make Them" to verify the magazine dimensions. I'm still working on the case, and hope to have the clock running soon. thanks drive carefully

Howdy, I've modified my homebuilt sync, I'm either using ball bearings on all the arbor pivots, or I made the part as a ball bearing. The roller is now a ball bearing but is still mounted on its' arbor with hand broached pivot bearings, the back click is a ball bearing, and its' arbor is also on ball bearings. Because the click ball bearing has an inner and outer race, the bend of the click wire cannot make contact with the outer race, and thus is free turning. I "pinched" (made wider) the end of the wire to keep the bearing in position on the wire.
The armature pivots, gravity arm catch pivots, count wheel pivots, and the gravity arm pivots are all on ball bearings, using Dynaroll SR0 A5 .0469 bore...I'm not trying to improve the synchronome so much as improving my lack of ability to make hand broached pivot bearings to a high degree of freedom and accuracy....

I hope to have this clock running by early next week with an unannealed Invar pendulum rod. This weekend I'm beginning the assembly of an inert atmosphere heat treat oven to anneal the Invar rods I have.

thanks drive carefully. johnrobinson

Hello chaps

Does anyone know where I might be able to obtain a count wheel for a Synchronome master clock??

Regards

Brian

Hi there, Brian,

Why don't you make your own count wheel? If you have either 'Electrical Timekeeping' or 'Electric Clocks and how to make them' both by F. Hope-Jones, they each include a drawing of the count wheel.

One merit of the Synchronome is that the pitch accuracy of the count wheel isn't too demanding - it only has to be precise enough for the pawl to gather at least one but not more than one tooth at each swing of the pendulum. Subsequent action, i.e. release of the gravity arm, only occurs once per revolution of the count wheel.

I'll retreat to my dugout now!!!!!!!!!!!!!!!!!!

Best regards,

Swarf, Mostly!

Hi...thanks for the thought. Sadly, I don't have the equipment to make a count wheel so am keen to track one down. Am I right in thinking they used to be fairly readily available?

Regards

Brian

The minimum of equipment is required for the count wheel. Jewelers saw and a couple of files and the ability to mark out. If you can cross out a clock wheel you can make the count wheel as it's just a rachet and doesn't mesh with anything. Give it a go.

regards Martin

Good advice..thanks, I'll get on the case!

Brian