A homebrew retro digital 'Flip Clock'

[David G4EBT]

Elsewhere on the forum there is a wanted request from a forum member for a digital 'flip clock'. Rather than take that request off topic I thought it better to start a separate thread in the 'Homebrew' section to provide details of a flip clock that I made a couple of years or so ago from an N.O.S flip clock movement which cost just £2.00. My son had been after a ‘flip clock’ and found that they seem to command high prices on auction sites. I recalled that I'd seen such bare clock movements in Birkett's shop in Lincoln some years ago, so I enquired of John if he still had any, which he did - £2.00 each. The clocks were originally made for electric cookers and I guess they became surplus due to the advent of fluorescent digital displays.

My son asked if I could box one up for him in a dark oak box with a dark front panel - black or gunmetal and I've attached some pics of the end result which might be of interest. The case is 6" long x 4" deep x 3.5" high, on feet 1/2" high. The front and back panels are scrap PCB material, and the wood was from scrap oak flooring cut to thickness on a bandsaw the comb-jointed on my home-brew comb-joint router jig jig, so the total cost was just £2.00 for the movement - a cheap 'stocking filler' for Christmas 2012! It has a neon to light up the display, which it's as dim as a Toc H lamp, but at two quid, I'd hardly grumble about that - the digits are large, stand out well, but a brighter neon could easily be fitted if better illumination is desired.

John Birkett said at the time I visited in 2012 that he had quite a few left. You can contact Birkett's on 01522 520767. It’s a fascinating shop and he has literally tons of junk. It's located at 22 The Strait Lincoln, LN2 1JD. His web address is: http://www.zyra.org.uk/birkett.htm but it's not a lot of use as you can't order or even send an e-mail and there's no on-line catalogue, so really, you need to ring up. Just say that you understand he has cooker clock modules with flip digits for sale - does he still have some left? He'd had them for at least 25 years so he hasn't had a run on them! I'm not sure John opens every day as he's in his eighties now, and not in the best of health.

There are some bits of redundant mechanism which need to be removed from the RH side and rear, which will be self-apparent but I’ve included some pics - the first pic shows the redundant bits on the RH side - the second is with those bits removed. The shaft on the RH side which you use to rotate the digits to set the time is about 3mm diam, so I turned a little brass bush on the lathe with a 6.4mm outside diameter and to secure it onto the shaft I used a 4BA grub screw by drilling and tapping 4BA through the side of the bush to accept the screw. This enabled a small knob to be fitted to the shaft. (Without a lathe, a short piece of 6.4mm brass rod could be carefully drilled on a pillar drill).

At the rear of the movement there's a 'choc block' two-pin terminal strip, a cable grip and plenty of options for earthing the metalwork with a solder tag and screw. I made the clock to my son's wishes - not my own - I'd have preferred something a little less sombre. He wanted a simple, plain, dark oak box, which is what he got and he was happy with the end result. There are of course other options for boxing up to suit one’s own preferences, such as acrylics etc. To a large extent the dimensions of the case are dictated by the dimensions of the clock movement. The case could have been a little less high - perhaps half an inch, but couldn't have been any less wide or less deep. I felt that if I'd have made the case less high, there would be only about 15mm above and below the aperture for the digits, but about 40mm either side of the digits. I thought that those proportions would look rather odd.


Hope that’s of interest.

[cmjones01]

That looks really nice. I remember those clock modules: I think Bull Electrical were selling them in the late 80s with a pile of bits of acrylic which could be glued together in to a case, which promptly fell apart again. I've probably still got one somewhere! Funny that they've come back in to fashion.

Chris

[OscarFoxtrot]

Originally Posted by cmjones01

That looks really nice. I remember those clock modules: I think Bull Electrical were selling them in the late 80s

... I think I remember the "digital clock kit"

[Mike Phelan]

Nice job, David. You just need to design the perpetual calendar now!

[Nymrod121]

That looks very good, David. I just hope that your son doesn't develop a similar interest in owning a reproduction 'airport terminal arrivals/departures board' ... !

[David G4EBT]

I sincerely hope not!!

Those boards are very impressive, I must admit, and presumably very reliable too. LED displays are not nearly so 'sexy' as the electro-mechanical ones. There's a bit about the history of flip displays here:

http://www.flip-clock.net/discoverflipclocks.html

The Solari board, the name by which it would become known, after the Italian inventor - a self-taught engineer - was first installed at Liège-Guillemins station in Belgium in 1956 and became the worldwide industry standard display. The company he founded - Solari di Udine - is still in business, manufacturing commercial flap displays. Bare movements similar to the Birkett £2.00 jobbies (though battery powered) are available new (made in China - where else?) here, for those with deep pockets:

http://www.flip-clock.net/flipclock_deskflipalarm.html

[Nymrod121]

Fascinating! - thank you David.

Best wishes
Guy

[Robsradio]

Originally Posted by Mike Phelan

Nice job, David. You just need to design the perpetual calendar now!

I have a 1950s Solari Udine CP2, this features a perpetual calendar and it's all done with cams and gears, great bit of kit!

[terrybull]

I visit Lincoln about once a week. If anyone wants anything from Birketts I will collect it and post it to you at cost.

[Robsradio]

That is a very tempting offer thank you .... but I am trying to resist