First seen in advertising November 15, 1972 the Calson MiniMod was priced from $7.88 to $11.99 (equivalent to $46.29 to $70.43 in 2017 dollars). By 1973 you could find the clock priced at $5.99 ($34.03 in 2017)
The Caslon MiniMod has no other features besides the flip clock. The clock's advertised dimensions are 5 1/4 inches wide, 3 3/4 inches tall and 3 1/4 inches deep. This is close enough to the actual measures, but the clock's shape does not lend itself to being easily measured.
It's an unusually small flip clock with unusual styling, the retangular clock face cradled by a semi-oval shaped case resting on a base that looks like a trophy stand. It sits high enough up on this stand that you could wrap the cord around it (I saw that on eBay once ... please don't do that).
The front of the clock face is real glass and the font face of the white on black digits is compressed, but with thick lines; kind of angular and otherwise without much flair. It seems somewhat quirky, not really representative of typical fonts of the period, and not really easy to read.
Unfortunately, this particular formerly "frosty white" flip clock had become very, very yellowed over the approximately 45 years of it's existence.
Turning a plastic banana clock back to it's former glory.
Whitening flip clocks was not commonly discussed until about 2013. But "De-yellowing" plastic has been around at least since 2009 (this being performed by collectors of vintage computers among other things). Before this, people had assumed that the plastic had become permanently yellowed due to age.
In this Google driven world of free information you'll find several alternatives for de-yellowing plastic. But FlipClockFans rule number two of FlipClockery states: Use the simplest and cheapest method! All you'll need is some light, and a bottle of the stuff people use to bleach their hair (hydrogen peroxide containing creme developer).
After disassembly, the Caslon flip clock was placed in a bowl then coated in Salon Care 50 Volume Creme Developer. Typically only licensed hair care professionals can get a strength up to 50 (us lowly consumers can only purchase 40 volume). I have to confess that I have access to a licensed professional who supplied me with my stuff. The 40 probably would work just as good, I'm sure.
In any event, after coating the surfaces of the yellowed plastic generously in the hydrogen peroxide containing gel, I covered the bowl with plastic wrap (to decrease evaporation) and irradiated it with bulbs on my desk. Later, I moved the operation to my garage and finished the process with a halogen shop lamp. No more than 72 hours after starting, the yellowing disappeared.
What causes plastics to yellow in the first place?
UV light reacts with what are called brominated (bromine containing) flame retardants that have been added to plastics. This reaction liberates bromine allowing it to bond to oxygen. Oxides of bromine have a yellow to yellow-orange color and these products remain bound within the matrix of the outer surface of the plastic, giving us the aged, yellow look. When hydrogen peroxide reacts with these molecules, the bromine oxides are converted to hydrogen bromide which is colorless. It is asserted by many that the action of the hydrogen peroxide is enhanced by UV light (the cause becomes part of the solution).
While I used to question the need for UV light, my experience tends to support the use of UV light. In the case of this MiniMod Clock, I started the reaction by using two household LED bulbs. They are broad spectrum and actually do have some light in the UV spectrum. When I switched over the halogen shop light, I noticed a significant increase in the speed of the process. Halogen lights are known to have significantly more UV light in their spectrum.
So now this little piece of flip clock history has joined the other early flip clocks in FlipClockFans studios.
Video detailing the disassembly and the de-yellowing process
What was happening In 1972
Cost of a gallon of Gas: 55 cents
Ford Pinto priced at $2,078
Richard Nixon elected for 2nd Term as US president.
11 Israel Athletes murdered by Arab Gunman at Munich Olympics on September 6th, 1972.
Start of the Watergate Scandal - Five White House operatives arrested for burglarizing the offices of the Democratic National Committee.
The Equal Rights Amendment (equality of the sexes) passed by the U.S. Senate on March 22, 1972.
Atari releases PONG, the first video game to achieve commercial success.
from The People History
References:
Advertisement
The Press Democrat - Santa Rosa, CA - July 3, 1973 pg 13.
Brominated flame retardant
more info from wikipedia
De-yellowing plastic - the stain isn't permanent after all (2009)
"Exile" forum entry from 2009 (exile.net)
Salon Care 40 Volume Creme Developer
Buy on Amazon.com
To comment see the forum entry.