1973 >> June >> Porcelain Insulator News  

Porcelain Insulator News
by Jack H. Tod

Reprinted from "INSULATORS - Crown Jewels of the Wire", June 1973, page 21

Since I have been back east on an insulator research trip all of April and most of May, general porcelain news items have been deferred to later issues. Please realize that our news copy deadline is 40 days prior to the first of the month of issue.

Pin type insulators are the main item of interest to the majority of the collectors, but we continue to receive many more questions on other types of porcelains besides pin types and have received a number of notes saying that this type of news is appreciated. I have even received a few letters recently asking for more general information type of articles like we have had in past issues. Thus we use our allotted space in this issue for some of this and hope that it will be helpful and interesting to you.


WIRING INSULATORS

Although there was a considerable need for miscellaneous types of "wiring" insulators for communications lines ever since the middle of the nineteenth century, our story really begins when Thomas Edison invented the incandescent lamp in 1881. Within a few short years houses by the thousands in every city were being wired for electric lights. A few years later than that, by the millions.

In the 1880's wires were strung through the houses in many fashions, most generally single wires tied to small wooden or porcelain knobs and pairs held down with wooden cleats similar to the later porcelain ones. Fires and serious electrical shock were probably the order of the day, and evidently the insurance companies had finally had it by about 1892. The following quote from an Oct. 1892 trade magazine is in reference to a newly patented 2-wire cleat by Pass & Seymour: "The cleat ... is intended to take the place of those of wood, now in general use."

In Nov. 1892, in reference to a newly patented adjustable 2-wire porcelain cleat by E. G. Bernard Co., there is this remark: "The accompanying illustration shows a new form of china cleat especially designed to meet the requirements of insurance experts, who have recently prohibited the use of wood for this purpose."

There are several patents in the 1883-89 period for wiring knobs and cleats, but the use of these items in a big way really dates from the 1892 period. The earliest patent for a cleat of the "modern" form was granted Sep. 11, 1891, and there are numerous patents on wiring knobs and cleats in the 1892-93 period.

It was also during this same time that a number of companies turned from making door knobs and dishware to making electrical porcelain - mostly "wiring insulators". Even though R. Thomas & Sons and several other companies had an early start in this field, companies formed in the 1890's and later years became the dominant ones.

Pass & Seymour (Syracuse, N.Y., founded 1890) seemed to make the most headlines in trade magazines with their new products along this line. Several other companies joined the bandwagon at about this time and a host more in the 1897- 1903 period.

Wiring houses for electric lights became big business in a hurry, and there was a need for these insulators by the millions. Considering the large number of insulators installed, it is only natural that everybody was trying to come up with designs which would do the job better and quicker. The patents are full of all sorts of creations of self-tying knobs in the 1890's, just as they are with all forms of pin type insulators which would eliminate the need of a tie-wire.

By the early 1900's, the standard wiring insulators were the now-familiar "nail knob" and the #334, 2-wire cleats. The tremendously increasing market for these insulators naturally attracted interest, and companies were formed with great rapidity in the 1905-1920 period just for making standard porcelain items mainly these nail knobs and cleats. Some of the bigger ones formed in this period were Findlay (1911), Illinois (1910), General Porcelain (1913) and Federal (1917). But there were dozens of others besides these.

By the mid-1920's there were so many companies making these wiring insulators that the supply caught up with the demand, and things started to get competitive - to the point that a number of companies went broke or otherwise dropped out of the picture. (The last big company founded to make dry press porcelain was Knox, 1923.) Some managed a more graceful departure by virtue of being bought up by the stronger ones, such as when General Porcelain Co. and five others merged to become Porcelain Products, Inc. In 1927 (bought by A. B. Chance Co. in 1956 and the dry press plant sold to Clarken Co. in the 1960's).

Still another reason for the rapid demise of the "nail knob" industry was the rapid adoption of new wiring codes in the 1920's and 1930's by most larger cities and towns, such codes calling for strictly conduited wiring. Except for small, unincorporated communities and some rural areas nail knobs and the like are now a thing of the past.

I have listed at the end of this article the companies known to have made standard porcelain items, and "wiring" insulator types almost for certain, as taken from information in my files. There could be more, but I feel the list is nearly complete. Where markings are known for the particular companies, these are listed in the Porcelain Column of Crown Jewels, issues of Oct, Nov, Doe 1972.


NAIL KNOBS

Pictured at the right is the proverbial "Nail Knob" as we collectors prefer to call it. To me this lowly little porcelain insulator is something special. True, it may not be as exotic as those cobalt blue pin types, but just look at what it has going for it.

This insulator wired the houses of the United States, and that's no small accomplishment More companies made this type of insulator than made all others combined. More company markings exist on nail knobs than on any other insulator varieties. More of these insulators were made than all other standard porcelain items combined.

Technically speaking, these are #5 1/2 Split Knobs, but the manufacturers labeled the boxes of them "Nail Knobs". In the industry when these were made and sold with the nail (or screw) installed with a leather washer at the top and a keeper at the bottom, they were termed "assembled knobs".

Some collectors have started calling these "Nailits", most probably just to use a catchy, one-word name, but I prefer to use the term "Nail Knob" since NAILIT is the tradename used by one of the manufacturers - as is also NAILIN, by the way. Although used ones found with captive screws should be called Screw Knobs I suppose, I just call all the Split #5 1/2 items Nail Knobs and let it go at that.

In general all the nail knobs are the Standard Porcelain #5 1/2 size, either old code (1") or new code (1-1/8") sizes - usually the later. These are the super common ones we are talking about. They also come in smaller (a split 3/4" x 1-5/8", rare) size and several larger sizes, usually a Split #3 screw knob type. These larger ones are far less common than the #5 1/2 but are only scarce at best.

For all practical purposes, all (99.9999%) are white glaze. The one that is commonly seen with black glaze has a PHILCO marking, and I believe it was sold as part of radio antenna installation kits. The majority of the different varieties you will get will be unglazed.

The overall size, the crowns and the bases of all the different nail knobs are generally about the same from a mechanical standpoint, but there are many differences at the juncture point. Most have two grooves, but some have two grooves in both directions (4 total). Most tops have just flat, corrugated surfaces at the juncture, but some have mating wire grooves to go with the ones in the bottom part.

In general the mating surfaces are flat except for a circular aligning tongue-and-groove at the nail hole, but there are various patented types (mostly common) with protective barriers between the wires and the nail. The most common of these are the "B & D", "Buckeye" and "Detroit" types, and they will be included in a later article. They are all at least slightly scarcer than the ordinary type.

The fact that these come in two mating parts can lead to problems. If you find ones with markings on both the cap and base, don't relate the markings unless you are certain that the two parts are a set. If you find a dozen caps and a dozen bases all in one box at a flea market, you can generally assume that they went together. Even if you are certain you have matching sets at the time, you still have a problem keeping them together if you have a large collection and the usual duplicates, and I have found it best to attach them right away before they get mixed up. Here are three ways to do this, and you can pick what appeals to you - or even something better.

Method (1) appeals to some as it tends to restore the specimens to their original condition. I use #16 spike and a thin #4 washer, seated just far enough to clear the base. Cut leather from scrap. For method (2) make some small wire rings and get some little "baggie" rubber bands. Use a wire hook to pull the end of the band thru the hole. For method (3) bend a small copper wire to form a loop in the middle, shove the ends up through the hole from the bottom and bend the ends over the cap.

Methods (1) and (2) allow the juncture to be seen without dismounting. Methods (2) and (3) allow the specimens to be set on a shelf while (1) requires a wooden block with holes drilled in it to mount the specimens upright. Thus the (2) looks best, but rubber bands tend to give up and break with time.

The fun in collecting nail knobs in in the markings. The market was very competitive for these, and since they are all dry press items, the dies were generally always marked. Markings contain one or more of the following: Manufacturer's name, the trademark, tradename, catalog number, patent number, patent date - or nothing!

Some of the interesting tradenames appearing on the nail knob crowns refer to the tightness which the insulator grips the wires: ALLIGATOR, BULL DOG, GRIP-IT WEDGE, HOLD FAST, etc. Other tradenames relate to the simplicity of use of the maker's product over others: EVEREADY, CINCH, IDEAL, JIFFY, NAILIN, NAILIT, READY, SCREWIT, etc. See the Oct, Nov, Dec 1972 issues of Crown Jewels for the attribution of these and other markings you'll find.

CLEATS 

Collecting wiring cleats goes hand in hand with the nail knobs, and practically everything said above for the nail knobs could be repeated here.

The most common of all the different wiring cleats is pictured above. This particular style and size of 2-wire cleat was cataloged by many of the companies as the #334, so if you collect these just label your want lists as "334 CLEATS" and we'll know what you're talking about.

This same size was also made in 3-wire style usually cataloged as a #337, but if you collect cleats you will probably soon see that the fun lies in the search for the different markings and you don't care if the specimen is a 2--wire or 3-wire cleat.

There is a style option with a tall base which keeps the wires 1" off the wiring surface instead of 1/2" as does the normal #334 size. There are also slightly heavier duty types of both the low and tall styles - same hole spacing but thicker. All of these variations are much less common than the #334 pictured above.

There are a number of early styles of cleats very similar to the shape of the one above except for differences at the juncture point. All of these patented early types are rather scarce (some are rare), whereas the normal ones with the smooth mating surfaces are very common.

Markings on cleats include most of the same company names and trademarks that are on nail knobs, but that is where it ends. There is a conspicuous absence of all the fancy tradenames that you see on nail knobs. No magic "SQUEEZITS" or "PRESTO" names here. This is difficult to understand since cleats were used in great quantities for surface wiring and they held the wire as firmly and were as quick to install as the nail knobs.

Whereas nail knobs are rather common glazed, 334 cleats were generally sold unglazed. They were available glazed (always white) on special order, and the glazed ones are rare by comparison with the others.

The fact that both halves of the cleat are the same, combined with the fact that all companies made the same size (or very nearly so in some cases), leads to a problem in collecting them. Many boxes of cleats at flea markets and old electrical shops yield markings we need for the collection, but sometimes we get only on half the pair. So you just mark "1/2" on your checklist instead of checking it off and keep on looking for a mating half. In any event, we don't have the problem with getting tops and bottoms mixed up as with nail knobs since both halves of the cleats are identical.

Mounting the cleats is simple. Just put the halves together and hold them with a small, light-colored rubber band. If you want to improve the appearance for those spots where you have found only half the cleat so far, you can "cheat" a bit by putting a miscellaneous extra 1/2-cleat on the bottom. Use a colored rubber band on these so you won't mistakenly get this checked off your want list someday before you get a mating half.


I suppose this article wouldn't be complete if we didn't mention something about collector value of Nail Knobs and 334 Cleats. Just as many people ask the "How much?" question as the "What is?" question.

Nail knobs as such are positively dirt common. They were made literally by the billions. It would not have been impossible for even one large company such as Knox, Findlay, Illinois or P.P. to make a million assembled nail knobs in one month during the peak period of these insulators from 1910 to 1930. Considering the many companies that made them for so many years, you can use your own imagination as to how many were made in total.

What's more, a large percentage of these knobs are still around! They are small and don't take much space. Most people are not aware that open surface wiring is no longer permitted in electrical codes, and these little insulators still look like they are of useful value to most people. They are even saved when the old barn is torn down and are carefully put away in a coffee can in the shed out back. It never dawned on anybody to just toss these in the wastebasket as unusable junk.

Old electrical wiring companies, junk yards and secondhand stores are good places to look for this. I saw one electrical shop in California (merely stopped for gas across the street) that had bins and bins of this all along the walls of two rooms. In four hours of picking through this I didn't make a dent - but found many knobs and cleats I didn't have. A secondhand store in Phoenix had 3 barrels of mixed items, and it took me over two days to go through this as fast as I could - buying for a $5 bill about 100 pounds I picked out. One yard here has 11 crates of KNOX cleats out in the back (unopened factory crates). Another has eight full factory barrels of Knox wall tubes just as they came from the factory years ago (I estimated about 5,000 tubes per barrel). Anyone for a Knox wall tube - plus 39,999 duplicates?

You can generally pick out and buy nail knobs at the flea markets for about a nickel each, sometimes 2 for a nickel, sometimes up to a whole dime. Ditto for cleats. And as you can see, you can have a field day for practically nothing at other places.

So much for nail knobs and cleats themselves. Now we get down to the fact that we have a fairly large collection and new additions aren't coming along very fast. You are now after those older names, the ones from the small and obscure companies who weren't in business very long, the other half to complete a pet cleat. This is where you start chasing 'em just a bit. Quarters start flowing at the flea market where a dime used to be your limit - then maybe a half dollar, or even a dollar bill for a cleat with a name never reported before.

I simply advise you to take it easy when you start out because the common markings are so common. Save your big money for later on after you have the easy ones. What your limit is depends on you - not on what I or others will pay for them. But one thing is for sure; you can turn in just one of your fancy high-priced pin types and have a ball for a long time collecting nail knobs and cleats. Just think of how much more history is wrapped up in those two collections that in that one other insulator!


My research indicates the companies shown below manufactured Standard Porcelain items, and most probably including nail knobs and 334-type cleats. In most cases I have shown dates encompassing the standard porcelain manufacture or the period when the company went by that name and not necessarily representing the founding or closing dates of the factory itself. As such, some dates are estimated and marked ( *). .

Adamant Porcelain Co. East Liverpool, Ohio  (Ca 1910 - 25)*
Akron Smoking Pipe Co.(see Mogadore Insulator Co. after 1900 date) Mogadore, Ohio (1896-1900*),
American Insulator Corp. New Freedom, Pa. (Circa 1920*)
American Porcelain Co., The E. Liverpool, O. (Ca 1920*)
Anderson Porcelain Co. E. Liverpool, 0.  (1899 - 1911)
Barnard & Co., B. S. New York City  (1905 - 1920+)
Bernard, E. G. Troy, N.Y. (Circa 1890* - ??)
Boch-Metsch Porc. Co., The E. Liverpool, 0. (1920 - ??)
Brunt Porcelain Co., G. F. E. Liverpool, 0 (1898 - 1925)
Central Electric Co. Chicago, Ill. (Circa 1890* - ??)
Ceramic Specialties Co. E. Liverpool, 0. (Ca. "current")
Cincinnati Porcelain Co. Cincinnati, 0. (1920 - 1927)
Colonial Insulator Co. Akron, 0. (pre 1920 - "recent")
Cook Pottery Co. Trenton, N.J.  (1897 - present)
Davidson Porcelain Co. E. Liverpool, 0.  (1920 - ??)
Diamond Porcelain Co. Trenton, N.J. (?? - 1913)
Electrical Porcelain Co. E. Liverpool, 0.  (1897 - 1911)
Electrical Porc. & Mfg. Co. Trenton, N.J. (1895 - ??)
Empire China Works Brooklyn, N.Y.  (1878* - ??)
Erie Elec'l Equipment Co. Johnstown, Pa. (pre1920 - ??)
Eveready Porcelain Co. E. Liverpool, 0. (Circa 1920)
Federal Porcelain Co., The Carey, 0. (1917-1927)
Findlay Electrical Porcelain Co., The Findlay, 0. (1911- 27)
Freeman Electric Co., E. H. Trenton, N.J. (?? - ??)
General Electric Co. Schenectady, N.Y.  (1897 - current)
General Porcelain Co. Parkersburg, W. Va. (1913-1927)
Globe Porcelain Co. Trenton, N.J. (1913 - 1920's)
Greenwood Pottery Co. Trenton, N.J  (1897 - ??)
Hartford Faience Co. Hartford, Conn. (1900 - recent)
Illinois Electric Porcelain Co. Macomb, Ill.  (1910 - 1953)
Imperial Porcelain Works Trenton, N.J. (1895* - 1920's*)
Knox Porcelain Corp. Knoxville, Tenn. (1923 - present)
Leviton Mfg. Co., Inc. Brooklyn, N.Y.  (??)
Louthan Mfg. Co. E. Liverpool, 0. (??)
Machen Elec'l Mfg. Co. Phila, Pa. (pre1920 - ??)
Mogadore Insulator Co. Mogadore, 0. (1900-1920)
National Electrical Pore. Co. Carey, 0. (1914 - 1927)
National Porcelain Co.
(now is National Ceramic Co.)
Trenton, N.J . (1906 - present)
New Haven Porcelain Co. New Haven, W. Va. (?? - current)
New Jersey Porcelain Co. Trenton, N.J. (1920 - current)
Ohio Porcelain Co. E. Liverpool, 0. (1897 - 1911)
Pass & Seymour, Inc. Syracuse, N.Y. (1890 - present)
Peru Electric Mfg. Co. Peru, Ind. (1890* - 1925*)
Porcelain Products Inc. (Carey, Ohio plant) (1927 - 1958)
to Porcelain Products Co. (Carey, Ohio plant) (1959 - present)
Ravenswood Porcelain Co. Ravenswood, W. Va.  (1921 - 1927)
Security Insulator Co. New York  (1890* - ??)
Southern Electrical Porc. Co. Ervin , Tenn. (1920 - ??)
Superior Porc. Co. Parkersburg, W. Va. (1927 - present)
Superior Porcelain Works ? ?
Square-D Co. Peru, Ind. plant, (1925* - 1951)
Star Porcelain Co., The Trenton, N.J. (1915* - present)
Steward Mfg. Co., D. M. Chatanooga, Tenn. (1890* - present)
Sun Porcelain Co. Trenton, N.J. (1911* - 1913)
Thomas & Sons, R., E. Liverpool, 0. (1884 - 1957)
Trenle Porcelain Co. E. Liverpool, 0.  (1893- 1920's*)
Trenton China Co. Trenton, N.J.  (1888 - ??)
Trenton Porcelain Co. Trenton, N.J. (1900* - ??)
Union Elec'l Porcelain Co., (estab. 1865 as Union Porcelain Works, Brooklyn, N.Y.) Trenton, N.J.  (1880 - current)
Universal Clay Products Co. Sandusky, 0. (?? - present)
U. S. Elec. Porc. Co. Findlay, 0. (1903 - 1911)
Virginia Pottery Co. New Lexington, 0. (?? - 1913)
Ward Electric Co., Inc. Phila, Pa.  (1911 - 1920's*)
Washington Porcelain Co. Washington, N.J. (1917 - present)
Wheeling Tile Co. Wheeling, W. Va.  (1910* - ??)
Wisconsin Porcelain Co. Sun Prairie, Wis. (1919 - present

  *Estimated



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