1984 >> January >> Foreign Insulators  

Foreign Insulators
by Marilyn Albers

Reprinted from "INSULATORS - Crown Jewels of the Wire", January 1984, page 6

How to Remove Metal Pins from Foreign Insulators

I promised to show you insulators from Russia and Finland this month, but have decided to leave that for the next issue of Crown Jewels. At the time of this writing, Christmas is coming on like a freight train, and there is far too much good material on those insulators to make only a halfway attempt to cover it, due to the lack of time.

Besides, there is another subject that needs some attention, and it is long overdue. So many of you have written asking how to remove the metal pins from foreign insulators (both glass and porcelain) when those pins are in there tighter than Dick's hatband, and you'd really just as soon not break the insulators. Since I'm right in the middle of trying to disengage the pins from several French ones, I'll share with you what's been passed on to me, what works and what doesn't, and especially what not to do! Believe me, there's no more "gone" feeling than to stand over your kitchen sink, in a state of shock and disbelief, as you look at your prized insulator which is now in six pieces because you were a little over zealous in your attempts to get that pin out. I know, because, as I told one collector not long ago, I've got little insulator burial plots all over my back yard. 

First, a little background: The pinhole of a foreign insulator is usually threaded, or at least has annular rings or a series of small bumps or projections, only to provide more traction for the cement, and not to screw onto the pin. Very few are completely smooth.

Also, while it depends on the country, most of the metal pins are either threaded or notched on the end that goes up into the pinhole. The only smooth pins I've seen were Russian and were crude and probably made by hand. The purpose of the threads are, again, to provide extra grabbing power for the cement or other material used. (Exception: Cordeaux insulators from England, which are designed to screw directly onto the metal pin.) But in nearly all cases, the pinhole is larger than the pin, even though both may be threaded, and the bottom line is that something must be used to hold the two together!

I have seen several materials used: Narrow strips of burlap lining the pinhole (Switzerland); string or hemp dipped in a tar-like substance and wound around the pin (Denmark); human hair treated with creosote, or even animal skin (Germany); chalky white stuff that looks and acts like plaster of Paris (France and Belgium); crumbly, but tough, cement containing sulphur (Iran, Russia); "Portland" cement, like sidewalks are made of (England, France, Japan, Korea); etc. None of these substances were intended for easy removal! So you have several choices. (1) You can bring home a chunk of the original crossarm and mount your insulators that way; (2) or buy a block of wood and drill holes in it; (3) or use a hacksaw and saw the pin off even with the insulator base, so it will at least stand up, or (4) determine to remove that pin and read on.

The key word is PATIENCE. Promise yourself you are not in a hurry and it doesn't matter if it takes several weeks! It is worth the wait, and you really don't have to stand there and watch the process. You can go right on living, tending to other things in between sessions, and devote only a few minutes a day to your project.

You'll need rubber gloves, old clothes and shoes, a long sharp ice pick, a plastic bucket, a source of water, and a well ventilated place to work, preferably outside, and preferably away from nice green grass particularly, since you will be working with muriatic (hydrochloric) acid.

The easiest pins to remove are those cemented in with the white plaster of Paris type material. The best thing to do with these is to soak the insulators in plain water for several hours, and the cement actually gets gooey. Go easy with the ice pick. Scrape and bore and push, but avoid pounding or hacking at the cement. It doesn't take too much rough treatment to chip the inner skirt or threads. After you have worked your way down into the pinhole and removed most of the cement, you should start trying to move that pin. I just get down on the ground or floor with a pad under the insulator, and holding it secure with one hand, I push and pull on the pin until I feel or hear it begin to click or knock a bit. This means the band between pin and cement is beginning to give way. At this point, also, you can begin to tap gently on the end of the exposed pin with a pair of pliers, rotating the insulator between taps; or you can hold the insulator in your hand and tap the pin against a large rock, again rotating the insulator as you tap. This is where you really must resist the urge to hurry it up, and tap too hard. Take my word for it, you'll wish you hadn't. So what's your hurry? Stop and go do something else before you go too far.

If the pin is stuck in with hemp, burlap, or hair, use hydrochloric acid. If I have just a few pins to remove, say like six, I set the insulators, crown side down, pins up, in small plastic cups outside on the back porch away from anything else that is metal, because the acid fumes are corrosive and are absolute murder on garden tools. Using a glass or plastic measuring cup, I fill as much as I can of the pinhole with acid straight from the jug. Rubber gloves are a must, and it doesn't take too many gulps of hydrochloric acid fumes to remind me to hold my nose or turn my face away when I am pouring that acid. It's fascinating to see it begin to work at once on the metal pin, as well as the cement, as it bubbles and froths. Most cements contain lime, and hydrochloric acid dissolves this and breaks up the top layer of cement, letting you scrape it away after a few hours. Dump the acid and loose cement into a plastic bucket, rinse with water and dump that into the bucket, too. Then pour in fresh acid and let that work for a day. Each time you'll see progress, even if it's a tiny bit. You're moving in the right direction. Some cements are not affected as quickly as others, but all will eventually dissolve. Acid actually turns the topmost layer of Portland cement to slush, and it is the most satisfying of all to work with. You feel like you're getting somewhere! Once you get down far enough into the pinhole and have removed a good bit of the cement, you can begin to use the gentle tapping again to break that last bond. Once you have it moving, even just a little bit, you're on your way. It won't be long now. And if nothing else, the acid will eventually eat the pin. I remember a little Belgian glass insulator with an extremely fat pin and cement that just took forever to loosen. So it finally came down to watching the pin shrink little by little as the acid worked on it. When the pin finally came out, it was down to the size of a needle!

Hemp. string, hair, skin and burlap are all humble and temporary barriers in the face of hydrochloric acid. They eventually turn to mush, and the pins get wigglier and wigglier until there's nothing left to hold them in. Those are the fun kind.

If you have an insulator with just enough of the sawed off pin extending beyond the base to keep it from sitting flat on your shelf, I join you in your evil thoughts about the person who left it that way! All I can suggest is to go ahead with your acid and ice pick and work your way down into the cement. When it comes time to loosen that pin, you obviously can't tap on it, because there's not enough there; but try to grasp it firmly with the pliers as you begin to work it back and forth. The tight hold is important because one slip, and you may see chips flying.

If you have several, like dozens, of pins to remove, I suggest a plastic garbage can with a lid to set outside. Soak the insulators in a solution of four to five parts of water to one part of the acid, enough to cover. Remember that acid, as it works, creates heat, and if you have several cooking at once, that's quite a bit of heat. I have found only one type of foreign glass that cannot tolerate that much, and when I lifted the insulators out of the solution, the cement had loosened, but so had the inner skirts, and I had broken glass! So far I have not had any breakage when I just put pure acid in the pinholes, with the rest of the insulator well ventilated, so I actually prefer this method.

Glass insulators, as you know, can easily crack when subjected to rapid changes in temperature, so be careful to use tepid water when rinsing. Porcelain insulators seem to be tougher, and I've never cracked one by rinsing with hot or cold water.

Just a word about cleaning soot, grease and gunk off either glass or porcelain insulators. The safest and surest method I know is to soak them eight to twelve hours in oxalic acid solution; and then whatever dirt doesn't just come away easily may need a quick going over with an S.O.S. pad to loosen it, or a few more hours of soaking in the solution. Use a plastic bucket, as oxalic acid corrodes metal. Wear rubber gloves to protect your hands; but it is okay to put your bare hand into this mild acid solution if you do it quickly to retrieve an insulator and then rinse well with water; but I would not recommend it with hydrochloric acid.

If your drugstore does not stock oxalic acid crystals, ask your pharmacist to order it for you. I am able to buy it in one pound plastic jars, and I mix two ounces of the crystals with a gallon of water. This can be used over and over until it is so dirty you will want to throw it out and start over!

If you have any questions about any of this, just write me, and I'll try to answer them. Ask me anything except how to add more hours to the day -- I haven't figured that out yet, but I am working on it.



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