Simplex: Restoration
I won this old Simplex button press recorder in an online auction and Desmond Bull was kind enough to collect it for me, after we had both spotted it with more than a little interest.
There were no keys, the buttons were in a bad state, but the woodwork and clock seemed in reasonable condition.
My dining room was destined to be out of action for some time (again)…
When dismantled, all the internal mechanical parts were found to be corroded and stuck, so many hours spent cleaning, sanding, painting and greasing.
The theory of operation is as follows:
Each numbered button presses down on a sprung lever which has a stylus on the opposite end. All the styluses (styli?) are fed through a central holed bar. An adjacent paper covered drum is rotated by a linked rod from the clock movement. The rotation could be set for 12 or 24 hours. The paper would have a graph marked with time against worker number. When a button is pressed, the bell rings and the stylus punctures the paper at the corresponding worker/time point on the graph. The outer of the drum is made of rubber with grooves for each stylus to slot into.
The paper was held on to the drum by elastic bands, which would be removed and renewed by the time clerk each day. The removed paper would be used to note the workers attendance and therefore calculate pay.
By far the biggest challenge was the buttons themselves – some of the number inserts were missing, the rest indistinguishable.
With the help of my artist sister-in-law (http://www.theglassbarnstudio.co.uk/) we managed to laser cut circles from number printed and laminated card to replicate the originals. They had to be accurate enough to just fit under the chrome lip on each button.
The recorder uses a Seth Thomas 8 day 2 spring movement, which was common in USA time recorders at the time.
It worked perfectly, and only required light cleaning.
Having no key for the locks was also an issue. This meant dismantling the locks, looking at the lever arrangement and experimenting with cut out metal until I could establish the correct profile. I could then make a presentable key to fit.
There was a patent label inside the drum cover, and an instruction label on the inside of the case.
And with woodwork cleaned and polished, finally assembled, everything working, and looking not too bad.
