Reprinted from "INSULATORS - Crown Jewels of the Wire", July 1971, page 21
Besides collecting porcelain, I am quite interested in composition
insulators, especially the small rubber ones embossed CONTINENTAL RUBBER WORKS /
ERIE PA. USA. So one day while looking through the phone book I noticed an
advertisement for a Continental Rubber Works in Huntington Park. I then decided
to call them up and see if they were the same Continental that made the
Continental insulators. To my surprise, these insulators are still being
manufactured by Continental in Erie, Pennsylvania. The man with whom I talked on
the phone sent me a pamphlet on the five Continental insulators. The only one I
have never seen is the number RC-1 Spool (Case Transposition). I would like very
much to obtain one of these for my Continental collection.
I have enclosed a photocopy of the pamphlet I received and hope it may be of
use to you or your magazine. (Reproduced at 40% reduction on the following four
I have only 1 style of Continental insulator at this time, the R-4; I just
started collecting these a few weeks ago. Many collectors do not realize the
many styles of rubber insulators there are, and therefore think these are
worthless. The ones I am now looking for are: the R-3 (I have seen very few of
this style in use around here.), the R-5 (Similar to the extremely common R-4
used every where.) and the RC-1 spool. There is one more, of which I do not
know the number, but I will attempt to sketch it here.
If you have any of these for sale or know of anyone who does, please let me
One more thing. The ad I placed has brought "tons" of mail to me,
which is very helpful in locating some of the porcelain and glass I am looking
H. S. Blake
Granada Hills, Cal. 91344
Save Replacement Costs and Labor
Manufactured Exclusively by
CONTINENTAL RUBBER WORKS
Erie, Pennsylvania 16512
PROVED SUPERIOR TO GLASS, CERAMIC AND PORCELAIN INSULATORS IN LABORATORY TESTS AND THROUGH MORE THAN 25 YEARS
OF CONTINUOUS FIELD SERVICE
Savings in time and money are substantial.
Temperature, Fog, Humidity, Wind and Rain tests show Continental Rubber
Insulators have Preferable Characteristics.
Continental Rubber Insulators are the answer to the costly and troublesome
problems experienced with glass, ceramic and porcelain insulators. Users report
that the elimination of broken insulators during the first year more than pays
for rubber ones and results in reduced material and labor costs.
In addition, leakage and wire troubles occurring in wet weather due to
damaged insulators are avoided, thereby improving operating efficiency of
In a variety of applications, both laboratory and field tests prove the
superiority of rubber insulators in high wind, fog, humidity and extreme
temperature conditions. In rain, they are equivalent to glass and earthenware
Under severe mechanical strain, rubber insulators show no weakening at
critical points of support, such as at corners and terminals, They have greater
surface restivity, lessen wire breakage and are self- cleaning.
For use on Electric Power, Telephone and Telegraph Lines and on Railroad Communications Lines.
R-3 Insulator (Detail)
Design, size and pin data:
The R 3 rubber insulator has a smooth interior hole that makes a tight-fit, self- threading grip on the standard steel spindle without cob.
R-4 Insulator (Detail)
The R-4 rubber insulator has interior threading which gives a tight, screw fit on either the standard wood pin or
on the steel pin with wood cob.
R-5 Insulator (Detail)
The R 5 rubber insulator is designed for use at points involving heavy wire
loads or severe stresses. Tight grip, self threading hole for either the long or short shank A. T. & T. type
RC-1 Insulator (Detail)
The RC-1 rubber insulator is specifically designed for use on the Case
LABORATORY TEST GRAPHS SHOW COMPARISONS
SURFACE RESISTIVITY OF CONTINENTAL PIN-TYPE RUBBER INSULATORS AND STANDARD
GLASS INSULATORS AT ELEVATED TEMPERATURE AND HUMIDITY
(Detail Figure 1)
RUBBER INSULATORS RELATIVE INSULATION RESISTANCE Of OPEN WIRE CIRCUITS
(Detail Figure 2)
AVERAGE ANNUAL RELATIVE PERFORMANCE OBSERVED UNDER HEAVY FOG CONDITIONS
For additional information, contact your nearest (Detail)
Continental Rubber Works
Buffalo, New York .. ...... (716) 852-0018 Memphis, Tennessee (901) 327-6194
Chicago. Illinois ...... (312) 276-7474 New York. New York (201) 933-5577
Cleveland. Ohio .. .. ...... (216) 631-0482 Philadelphia. Pennsylvania. (215)
Detroit, Michigan ...... (313) 547-8181 St. Louis, Missouri .(314) 531-4088
Kansas City, Missouri, ...... (816) 444-6720 Shreveport, Louisiana .(318)
Huntington Park, California.. ...(213) 581-0143
CONTINENTAL RUBBER WORKS