Ceramic Spikes (Ecodefense)

Ceramic Spikes

Foiling the Detectors: Non-Metallic Tree Spikes

Clay bodies can be stiffened and made even more durable by the addition of “grog,” a gritty, sand-like material usually made of a high-fired refractory material (ground stoneware) or simply a pure quartz sand. Purchase this from a clay supplier, and specify an 80 or coarser screening. Do not buy fine powder grog, or “soft” grog made of weaker lower-fired materials. The grog is blended into the clay body through a process called “wedging”: kneading the material in by hand until it is thoroughly and evenly distributed throughout the clay. Since clay formulas vary from one type to another and from one company to the next, we cannot specify the amount of grog to add to your clay. Just add a little at a time until the clay feels a little coarser and stiffer. If you add too much, the clay will be hard to roll out and will not stick together well. The clay must remain “plastic” to allow you to readily shape it.

When handling the clay directly, always wear plastic gloves. The best types are the disposable examination gloves used by doctors and available at medical supply houses. More expensive, but more readily available, are the plastic gloves sold at all grocery stores in the kitchenware section. These types are more durable and will survive repeated use. Whichever type you use, obtain gloves with a skin-tight fit.

The pins are made simply by rolling the clay out to the desired thickness, and cutting it to the appropriate length. As with the metallic pins described above, you will have to use a drill to make a hole in the tree for inserting the pin. Choose your drill (cordless battery-type or old fashioned brace and bit) and find the largest bit you can readily use, up to one inch in diameter. Experiment on a recently fallen tree to insure that your drill and bit combination allows you to drill a hole up to four or five inches deep. The thicker your ceramic pin is, the more likely it is to either dull or break a sawmill blade. Therefore, if you can drill one-inch diameter holes, roll out the clay to a one-inch thickness. It will shrink some in drying and firing and will fit easily in a one-inch hole. As to pin length, four inches is plenty long; cut some shorter lengths, too, like two and three inches. This way, if your drill encounters a hard spot like a knot in the wood preventing you from drilling to the desired depth, you can use a shorter pin in the shallow hole.

Once your pins are rolled and cut, set them aside for a couple of weeks to thoroughly dry. They must be completely dry or they will break apart in firing. Also, make sure the clay is well-compressed during the rolling-out, as even tiny air pockets left inside the clay will blow up during firing.

Finally, your ceramic pins will be ready for the final stage in preparation — the firing. High temperature firing brings about chemical changes in the clay, causing the particles to bond together through vitrification. The end product is a material so hard it will easily scratch glass. In hardness, it ranks with some types of steel, although it will shatter under a heavy blow (making it unsuitable for spiking with hammers). Still, it is high enough on Mohs’ scale of hardness to cause damage to sawmill blades.

High-temperature firing can be achieved only in a gas-fired kiln. The pins must be fired to “cone 10,” which generally ranges from 2350 to 2400 degrees Fahrenheit. Firing to lower temperatures will not produce the same hardness. Following are some of the sources for gas firing:

Schools — Various college classes, adult education courses, and private instructors maintain gas kilns for student use.

Do-it-yourself — This entails purchasing a gas kiln and making the necessary hookups to a source of bottled LP gas. This all costs several hundred dollars. Take a college course or private course through a competent potter to learn the principles and mechanics of gas firing before undertaking this step yourself.

Private Individuals — Across the nation, there are thousands of professional potters selling their hand-thrown wares through art and craft shows attended by the public. Some of them will be amenable to letting you pay for custom firing in their kilns. This allows you to have the job done professionally. As a way of developing this contact, you might buy several pieces from them at a show, and ask if you can come to their studio later to buy more of their wares. If you appear to be a good customer, the potter might agree to fire a few dozen pins for you. To make sure your contact is a competent professional, check out their product line. They should carry a wide range of practical goods (cups, bowls, planters, etc.) and should stock large numbers of items. Avoid those who don’t seem to have much to choose from. Check the quality of their firing by breaking one of the inexpensive items you bought from them. The broken edge, revealing the inside of the fired clay, should be a medium to dark brown. If it appears very dark, almost blackish, the work is poorly fired (over-vitrification) and is too brittle. Do not let such a potter do your firing. Make sure you check the broken edge, as an external examination will not reveal this type of sloppy firing. Of course, make sure their goods are stoneware fired to a cone 10.

Security is of primary consideration when firing in someone else’s kiln, or when having a custom firing done. Do not use your real name. Never reveal the intended use of the ceramic pins unless the person handling the firing is a member of your spiking team. Do not attempt to recruit for your spiking team the person doing your firing unless it is a trusted friend of many years’ acquaintance, or a trusted relative. If possible have a trusted confidant handle the manufacture and firing of the pins at a location far from the forest where they will be used.

Have ready an air-tight reason for your intended use of the pins. Make up a convincing story, perhaps about how you plan to assemble them into an abstract sculpture. Use your imagination. The possibilities are limitless.

As a further means of obscuring their intended use, fire the pins in twelve inch lengths. These can later be cut-down to suitable lengths using a diamond wire hand saw available for $15 to $25 through a jeweler or lapidary supply house (found in most large cities).

It’s a good idea to have a member of your team take a course in pottery to become familiar with the materials, techniques, and terminology. This can help in manufacturing a convincing cover story for the firing of your peculiar pins.

Competent private instructors, although not as widely available, can be a good source of schooling and kiln access.

Inserting Ceramic Tree Spikes

A hand-powered brace and bit type of drill is both inexpensive and very effective for drilling large diameter holes in trees. It is also laborious and time-consuming, so you should plan to work on only six to a dozen trees per hit. Small numbers are sufficient if using non-metallic pins since the Freddies will be unable to find them; and if the lumber company cuts anyway, the pins will make it to the sawmill to attack the blades.

When a team is working in an area currently being logged, it is necessary to take security precautions that might not be necessary when working in a remote roadless area. Night work may be essential, and this creates additional problems. Absolutely critical is the ability to conceal all signs of your work. To gain this ability, you must practice during daylight hours in a safe and secluded location. Only by polishing your technique beforehand can you be sure you will leave no evidence at the scene. When chips of bark are glued back into place, there must be no telltale seams, cracks, or excess glue. All wood shavings must be carefully swept onto a towel and carried away a short distance for shallow burial. A dark terry cloth towel is recommended since the shavings will stick well to the rough surface.

When working at night, use a flashlight to carefully double-check your work when finished. The best flashlight is the current-issue GI flashlight available at most army surplus stores. It is made of green high-impact plastic, has an angled head (the light shines at a right angle to the body), and takes two “D” cell batteries. Unscrew the base cap and inside you’ll find a red plastic lens that fits under the “0” ring screwed onto the standard lens. This red light is sufficient for close work and will not ruin your night vision. If you insist on using a penlight type of flashlight, close one eye to protect at least half of your night vision. As with all tools, make sure all surfaces inside and out (including batteries) are wiped clean of fingerprints.

Your brace should be lightly oiled to insure silence, and you should carry a spare bit so that you can always work with a sharp bit. Since you have to lean into the brace to get maximum effectiveness, this tool is particularly effective on felled trees that have been limbed and bucked (cut into shorter lengths). These can be found either scattered about the logging site, or near skid trails or “landings” where they are piled for loading onto trucks.

When working in an area currently being logged, remain concealed by working low to the ground, hidden by shadows, or in areas where the terrain prevents viewing from any distance. Take these precautions when working in the dark. As in any spiking operation, it is essential to have an alert lookout well posted to guard the approaches. Working low will protect you from Forest Service enforcers using night vision devices. The lookout and pinner(s) need a signaling system of bird calls or short range radios. Always use a nondescript code on the radio.

It takes a brave monkeywrencher to work a logging site in the night, but remember that you have the choice of time and place. This advantage, when coupled with basic security precautions, will guarantee your success.

— T. O. Hellenbach

Field Notes

  • A simple way to test ceramic pins for metallic content is to run a magnet over them. If you detect any significant magnetic attraction, the pins probably contain ferrous metals, and maybe susceptible to metal detectors.

  • Instead of going to all the hassle of making your own ceramic pins or cut-ing rock slivers, just buy the ceramic rods that are used in knife sharpeners — “crock sticks.” They’re uniform in diameter and come in useful lengths. They can be broken into shorter lengths if you want. They can sometimes be purchased at flea markets for less than a buck. The uniform diameter allows a closer fit, which means you can drill a smaller hole faster and easier. Crock sticks are iron-free as well.

  • In green timber, white glue may not dry sufficiently quickly. In that case, try epoxy for plugging holes after inserting pins.

  • Ceramic insulators are made out of an extremely hard ceramic and are suitable for non-metallic tree spikes. Although they are being replaced by plastic insulators, they can often be found in old junk piles or in basements or storage sheds — some can still be seen in National Forests where ancient telephone lines led to fire lookouts (before radios). They also may still be available at large electrical supply stores. Use the standard placement and security methods for non-metallic spikes. Industrial ceramics are used for a wide variety of purposes, and with a little imaginative sleuthing, monkeywrenchers can probably find other readily-available forms suitable for spiking.

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