Terms used to categorize and describe plastic radio cabinets are loosely tossed around.
Frequent questions about terms used in radio descriptions prompted some research...
It turns out most of the terms used, such as Plaskon, Bakelite, Catalin, Beetle and Tenite are not types of plastics, but tradenames given by different manufacturers.
There were hundreds of different plastic industry recipes in the 1930s and '40s with similar characteristics,
which led to many plastic tradenames that few have heard of and the radios made from them
get funneled into these more popular tradename categories.
These are the 7 most widely used categories of radio plastics that radio collectors use in radio description.
Without getting too technical, here are descriptions on how to tell the difference with examples of each:
BAKELITE
The term, "bakelite" is used differently in radio collecting as opposed to jewelry collecting.
Bakelite jewelry collectors use the term "bakelite" for material that radio collectors call "catalin".
The "bakelite" term in radio collecting is generally reserved for cabinets
made by the high pressure phenolic casting process. Most commonly bakelites are browns and black,
although bakelite colors from yellow and red to blue and green are also found.
(see the green bakelite voltmeter at the bottom of this page and the bakelite color chart below).
Bakelite radio cabinets can have a beautiful gloss and sheen to them,
although bakelite colors are somewhat muted and the surface does not have the translucency and luster of a catalin radio cabinet.
Bakelite radio cabinets sometimes exhibit very nice marbling as seen in the Airline example below.
The Bakelite Corporation itself referred to all its plastics as "Bakelite", which included
their entire catalog of ureas, phenolics, cast resinoids, vinyls and more.
And other plastics manufacturers tweeked the forumulas, then labeling their phenolic plastics
with different names, such as "Durez" and "Insurok", all labeled "bakelite" by radio collectors today.
(see examples in the advertisements below)
These phenolics seems to be the most durable of the plastics used; sturdier,
with no shrinking and they could withstand heat better than other materials.
Unfortunately, lengthy UV exposure can make the surface dull and pourous,
and the original glossy sheen cannot be fully restored in these cases.
CATALIN
Catalin radio cabinets have the unmistakable, unique characteristics of poured resin.
Every color in the spectrum was available and catalin radio cabinets can be found
from solid colors to dramatic marbling of colors with varying degrees of translucency.
Once you have seen beautifully marbled catalin radios in person,
you quickly realize why there is the incredible demand for them.
The look and feel of catalin radios is truly unique and unparalleled with their glass-like surface.
Some examples command prices in the thousands, driven higher by certain cabinet designs,
colors, or marbling extent.
The creation of colorful catalin has been credited to Dr.Fritz Pollak, an analytic chemist from Vienna, Austria.
In the 1920s and '30s, Pollak had numerous patents for many plastic formulas and processes,
which also included the invention of urea resin (plaskon & beetle).
Dr. Pollak, a Czech living in Vienna along with Austrian chemist, Dr. Kurt Ripper, filed
patents detailing their catalin creation process in the mid '20s.
Many of Dr. Pollak's plastics patents can be found
here,
showing many of his filings across Europe and the US.
The Catalin Corporation bought the cast phenolic resin patent in 1927 when the Bakelite Corporation allowed it to expire.
Many other companies began using the process paying the Catalin Corp. a royalty for a license to do so.
These companies individually named the material, all which are now labeled as "catalin" by radio collectors.
Some names included, "Catalin" (Catalin Corp.), "Bakelite Cast Resin" (Bakelite Corp.), "Marblette" (Marblette Corp.),
"Fiberlon" (Fiberloid Corp)(used on the RCA 9TX1 Little Nipper II)
and "Opalon" (Monsanto)(used on the Emerson model 400).
And, like the Bakelite Corp., the Catalin Corp. offered other plastics such as Styrenes and others,
referring to all their plastics as "Catalin", adding confusion to plastics descriptions.
(see the Catalin Corp ads below)
Unfortunate characteristics of catalin are shrinkage and color fading from UV light.
Some color changes can be appealing, such as the change of alabaster catalin into
nice butterscotch or yellow-orange-golden hues.
Ultraviolet light exposure affects Catalin turning the phenolic resin surface into phenyl alcohol,
adding a yellowish brown hue to the outer layer changing the original color.
It then acts as a barrier blocking deeper color changes,
leaving the opportunity to sand and polish the surface back to the original bright color,
something that should be left to a catalin radio restoration professional.
In many cases, shrinkage around tight fitting chassis and glass dials caused the cabinets
or the dial glass to crack contributing to the scarcity of undamaged examples.
Catalin was also used for many different household items
PLASKON
Plaskon is a term generally used for urea molded, white and light pastel colored radio cabinets of the 30s & 40s.
The name, "Plaskon" is actually a trade name used for urea molded plastics made by the Libby-Owens-Ford Glass Co., Toledo, OH.
Many other plastic manufacturers also made urea molded cabinets, that all get funneled into this tradename labeled category.
Stress line cracks are a typical unfortunate characteristic of plaskon radios, and it is rare to find one without any.
Unlike Catalin radios, Plaskon radios do not change color over time.
BEETLE
Beetle is a term used by collectors for plaskon cabinets that are mottled or marbled
with green, browns, blues, oranges and blacks usually with a white cabinet base.
West coast radio makers' beetle radios were predominantly streaked with yellows and reds,
as found with Gilfillan, Packard Bell and the Remler Norco 158 seen in the gallery.
The marbling makes each example unique.
These cabinets were commonly listed as the "onyx" option in early radio advertisements,
and cost a few dollars more than their 'walnut' and 'ivory' cousins.
"Beetle" and "Beetleware" plastics are actually trade names used by the American Cyanamid Co., NY, NY for urea formaldehyde moldings.
Beetleware is said to have originated in Great Britain, where colorful speckled "Beetleware" dishware is often found,
perhaps the origination of the term now used to describe these radios.
Early plastic ads are confusing showing the same clock in both Plaskon and Beetle ads as seen below,
and with Beetle ads showing solid colors which would be described as "plaskon" in radio collecting.
Beetle and Plaskon are only two tradenames of the many urea molded plastics, just different manufacturers,
some adding colored speckling or marbling that are now described as "beetle".
Beetle radios commonly developed stress lines or cracks that tend to follow marbling lines,
or appear on the surface near the hot rectifier tube.
It is rare to find a beetle radio without any stress lines.
The 1931 Kadette model H is a very early example of a "beetle" radio cabinet.
PAINTED
Some radio manufacturers offered painted radio cabinets as an option.
From the late 1930s and into the '50s, painted finishes were generally applied to black or brown bakelite cabinets.
POLYSTYRENE
Although first developed in the late '30s, Styrenes were not widely used until the 1950s.
Polystyrene radios were made in many colors, sometimes marbled.
The plastic is somewhat fragile and brittle and easily cracked.
The surfaces are very easily scratched and also susceptable to heat damage.
These characteristics didn't dissuade it's use, likely because it was
more cost effective and perhaps some planned obsolescence.
TENITE
Tenite plastic was an unfortunate choice of another plastic used in radio construction.
Unfortunate because tenite turned out to be a very unstable plastic, unable to withstand the test of time.
Severe shrinkage and warping, sped up by heat and UV exposure, ended the lives of many radios that used tenite,
and to find radios with minimal tenite damage is rare.
Tenite was a name given by the Eastman Corp. (An Eastman Kodak subsidiary) for their cellulose acetate recipe.
Other plastic companies made cellulose acetate products as well.
For radio production, it was generally used for dials, grilles, esctcheons and knobs in the late '30s to the mid '40s.
A few radio models were made with tenite cabinets.
Tenite came in the all colors and sometimes included marbling in the plastic.
It can be very attractive, although its unfortunate aging characteristics make it somewhat undesireable.
The bakelite Philco radio below is an example with a tenite speaker grille with obvious warping.
It is a rare suvivor considering most were thrown out because grille and dial warping was too extreme.
The Pennwood Telechron red tenite clock below was probably never used and stored away from the elements,
as it has survived with no damage.
The marbled Gilbert clock looks like beetle plastic although tenite does not have
the rigid feel of urea-based plastics, with just a little bit of flexibility.
It exhibits some of the typical warping.
The radios shown in the Bakelite ad just below were made by General Television,
and one of the few radio models offered with a tenite cabinet.
(the model was also made with bakelite and the rare catalin cabinets seen in the ad)⤵
The tenite versions I've seen are bright red or green, with dramatic white marbling,
and 99% suffered tenite cabinet damage to some extent.
Urea Plastics (plaskon, beetle)
Strangely, the clock in the Beetle ad below is the same as the clock in the Plaskon ad above(!)
Phenolics (bakelite)
Cast Phenolics (catalin)
Many plastics manufacturers made cast phenolics catalin using their own names for the plastic.
For using the patented process, they each had a licensing agreement with the Catalin Corp.
Opalon was another cast phenolic catalin plastic,
the name given by its maker, Monsanto Plastics.
This Bakelite Corporation ad shows cellulose acetate and cast phenolic catalin plastic uses, including the rare Fada model L56 radio.
They are grouped together, referred to as "Bakelite Plastics".
The Catalin Corporation also made other plastics such as Styrenes and Polyethenes.
Although labeled "Catalin Styrene and Polyethylene",
these are not the cast phenolics that are now known as catalin plastic.
Catalin in Europe
Dr. Fritz Pollak and Dr. Kurt Ripper, chemists in Vienna have been credited with catalin's creation in the mid '20s.
See many of Dr. Pollak's plastics patents
here
.
...and from Grace's Guide (https://www.gracesguide.co.uk/Catalin)
Grace's Guide is the leading source of historical information on industry and manufacturing in Britain.
This web publication contains 148,272 pages of information and 233,809 images on early companies,
their products and the people who designed and built them.
"1937 To exploit the market in Europe and the Commonwealth, Catalin Ltd was set up in England,
not as a subsidiary of the American concern but autonomous - although using the latter's technology.
Dr Riesenfeld, who had acted as consultant in America and was one of the inventors of the process, became technical director.
(There were at this time two other companies producing cast phenolics:
Marblette in the USA and Raschig in Germany, with processes differing in some respects from that of Catalin.)
The British company was installed in the large building in Waltham Abbey, Essex,
that had housed the Nobel company in the First World War which made munitions.
The building provided ample space to accommodate a battery
of six nickel reaction vessels (called 'kettles' in the American style) and six large circulating hot-air ovens
for curing (i.e. hardening) the cast resins in their moulds, together with ancillary pumps,
boiler, workshops, laboratories and offices."
Cellulose Acetate
This is an early article about plastics use in radio cabinets from Electronics magazine, November 1937:
This article appeared in Radio Engineering magazine September 1936:
This article appeared in Radio Engineering magazine March 1937:
Plastics were taking over design construction of many objects,
found to be lighter, durable and cheaper than metals and woods used previously.
This article shows plastics being incorporated into automobile design.
Some of these concept car designs were created by George Walker, famous for
many of Detroit's great car designs including the 1955 Ford T-bird.
Walker is also known among radio collectors as a designer for Detrola Radio.
The Detrola model 197 was one of his great radio designs.
Below is a cover story article about collecting radios from the Monitoring Times 2011 July issue.
Click here to read the Monitoring Times radio collecting interview that the following article was compiled from
OR click the image below to read the article from the magazine page full-size JPGs.
Further reading on early plastics...
A more technical descriptive breakdown of Bakelite, Catalin, Plaskon, Urea and Beetle can be found in Steve Davis' excellent article about "Pre-War Plastics".
