Read an Excerpt
Creating Welded Sculpture
By Nathan Cabot Hale
Dover Publications, Inc.Copyright © 1968 Watson-Guptill Publications
All rights reserved.
Basic Tools of Welded Sculpture
The basic assumption of this book is that it is necessary for a sculptor-welder to have the same professional skill as a good job-welder. Not everyone agrees. These people do not seem to care about technique as long as the welds appear to hold together. The whole point is that a bad weld will not hold together in time. Only a skillfully made weld can last. If the sculptor develops the skill and craftsmanship of welding, he will be able to create any kind of weld and produce any kind of textured surface he desires.
In some quarters, there has been an irrational fight against technical skill and against knowledge of form construction in art for a number of years. Unfortunately, this controversy has spread into the new field of welded sculpture as well. I want to mention this debate since you will be subjected to these ideas, and will have to examine the facts and decide for yourself. Is it possible to "just go ahead and express yourself," or should you spend time accumulating basic technical skill in your chosen medium?
There have been a number of people who have taken up welded sculpture who have never mastered the fundamentals of craftsmanship. Some of them have gotten considerable recognition. But quite often in these cases, the sculptor has mastered another sculpture medium before he became interested in welding. In other words, he was already technically oriented to form. This orientation may give his forms a feeling of quality, but his sense of form does not guarantee he handles metal to his fullest capability. Actually, there is no real alternative to learning the craft of welded sculpture.
To learn welding for sculpture, I spent four years working in various kinds of welding shops. Since that time, I have worked steadily as a sculptor-welder with some success. Because I had been oriented toward art all my life, the years I spent learning the facts of metal work were difficult for me. However, the disciplined thinking of the industrial welder which I learned has been invaluable. I learned about structure, form functions, and work patterns. I learned a lot of bare facts about mechanical and geometrical shapes. In this book, I hope to crystallize my experiences for you so that you will not have to spend extra time in non-art jobs just to learn what someone else already knows. This book is intended to give you all the facts that a sculptor-welder will need.
As you have accepted me as your teacher, you will more or less acquire some of the things that I have learned the hard way. But all basic learning is done the hard way, namely through effort and determination. One of my main teaching goals is to encourage you to value craftsmanship and to acquire as much skill as you can. Teaching and learning are a two way proposition; even though I may not be right next to you to encourage you to put forth your best effort, I am there in spirit, urging you to master all these basic exercises.
Perhaps you have never given much thought to the matter of tools, but now that you are beginning to learn to do welded sculpture, I think it is a good idea for you to start out by understanding their origins and functions. Today, even though tools are important to the very existence of our society, they are too often taken for granted. Since welded sculpture uses some of the most advanced tools that man has developed, you must first understand the most basic thing about all tools. Tools are extensions of our human anatomical functions. They reach; they touch; they are used to model and shape our environment. Today, tools even affect the growth and development of the human species itself.
ORIGIN OF TOOLS
The use of tools goes back to the very beginning of mankind. The cultural development of the human race has gone hand in hand with the development and use of tools for shaping and understanding matter and energy. Even the stone axe and the stone drill had their period of growth and development at a time when they were an advanced and sophisticated technology.
A visit to the local museum of natural history will show you how the art of stone tool- making grew over periods of thousands of years. At the beginnings of the Egyptian culture, for example, stone-working had reached a very high peak of development. But someone started smelting metal from copper ore, and that gradually drove the stone tool- makers into a new line of business, although there may have been some academic die-hards who fought the "new-fangled" ways for a century or two. As a matter of fact, today, some of the older academic sculptors regard welding as heretical. This would seem to teach us that technology changes, but people do not.
By Greco-Roman times, the basic tool principles had all been discovered, and nothing really new has been added since that time. The new discoveries have come from adapting tool principles to new sources of motive energy: water, steam, electricity, gasoline, diesel, and nuclear power. Behind all these advances stand man's anatomical functions, and the basic modeling capacities of his life energy.
To me, there has always been an implied moral in this understanding of the origin of tools. I feel that the user has an inherent responsibility for the best possible use of the tool. Some people never become quite worthy of the heritage of tools. They misuse the tools themselves; they do not appreciate or understand their meaning or history; and they never realize what an honor it is to be the inheritor of these implements that make wealth, shape human destiny, and model the world we live in.
So when you hold a tool in your hand, pause for a moment to reflect on the knowledge that you hold an object that took thousands of years of thought and striving to develop. A tool represents thousands of years of ancestral pondering; it is the crystallized hopes of your forefathers. In its very nature, a tool implies a logic, an understanding, and an obligation for you to do the best job of which you are capable.
Good sculptors love their tools and take delight in using them well. There is a sense of pleasure in the feel of a hammer, a pair of pliers, or any tool that you have carefully chosen and worked with for a few years. Tools are beautiful in themselves; and they grow more beautiful in time, the more they are used. Treat your tools well and kindly and they will serve you faithfully through the years.
A great part of welded sculpture depends on the use of tools. We could not make our kind of sculpture without them. And since part of the sculptor's reward results from the act of work itself, this knowledge of tools will give your experience a feeling of depth.
Although welded sculpture does involve a significant investment in tools, it requires less equipment than you might think. A great many tools are likely to be found in any well- equipped family tool box. Here are the basic tools you will need to begin welding.
1. Torch handle
2. Tips 1,2,3
3. Oxygen hose, 20'
4. Acetylene hose, 20'
5. Oxygen regulator
6. Acetylene regulator
7. Torch lighter
11. Cold Chisels
14. Screw driver
16. Steel tapemeasure
17. Steel square
Later on, you may want to add some of the other equipment I describe in this chapter, but these seventeen items are the only indispensable ones.
THE NATURE OF OXYGEN AND ACETYLENE
The most important tools you will use are two gases. One, oxygen, is always present in the earth's atmosphere and constitutes about one fifth of its volume. The English scientist, Joseph Priestley, discovered oxygen in 1774. It was later found that oxygen is the chief supporter of the combustion of all substances, although it does not burn by itself.
The other gas we use in welded sculpture is acetylene. This gas is not ordinarily found in the atmosphere but is, rather, a manufactured compound. In 1836, Edmund Davy compounded a highly flammable gas by mixing water with calcium carbide. This gas was later named acetylene. But it took sixty years until a French chemist named Le Chatelier discovered, in 1895, that when these gases were brought together under pressure and ignited, they produced a flame that would burn at a temperature between 5700º F. and 6300º F.
This discovery came at a time when science had developed ways to produce both oxygen and acetylene gases in quantity. This soon led to the development of the oxyacetylene welding process. Since this process had many useful applications, it was then and is still being improved by research. Today this welding process is used in every country of the world.
Both oxygen and acetylene are delivered to you compressed in steel cylinders (Fig. 1). Oxygen presents no problem when stored under high pressure. It is delivered to the commercial user in three different cylinder sizes: 63 cubic feet, 122 cubic feet, and 244 cubic feet.
Acetylene storage is more complicated since this gas will ignite spontaneously under pressures greater than fifteen pounds per square inch. So acetylene cylinders are air-tight and made of steel; the inner part is filled with porous material. Into this porous material, liquid acetone is injected. The acetone then absorbs acetylene gas in large amounts, and gives off the gas at safe pressures. Acetylene is delivered to commercial users in four cylinder sizes: 40 cubic feet, 100 cubic feet, 180 cubic feet, and 333 cubic feet.
Oxygen and acetylene cylinders in smaller sizes can be purchased directly from some welding supply houses. The larger cylinders are never sold, only rented. In some cases, it is just as convenient to order the cylinders on a rental basis as it is to buy them. Usually, there is no charge for the rental of the cylinder if the gases are used within a month's time; the only charge is for the volume of gas that the cylinders contain. After a month's time a slight charge (called a demurrage charge) is made—a few cents a day—until the cylinders are again picked up by the welding supply house, or until you return them. I own two sets of cylinders, and find this convenient for my own purposes. Some sculptors prefer to rent them. As a beginner, you would do best to rent a set of small cylinders at first.
Both oxygen and acetylene cylinders have valves on them that are similar to garden water taps. The acetylene cylinder differs by not having a handle; instead, it has just a square valve stem on which you use a special acetylene key wrench. Of course, these valves have a much finer control of outflow than water taps do; but even so, the outgoing pressure cannot be controlled properly by the valves. Since welding requires a steady and unvarying gas pressure coming to the torch, pressure regulators are used to maintain this steady flow of gases. These regulators fit onto the cylinder valves by threaded attachments.
The two types of regulators (Figs. 2 and 3) resemble each other in general appearance, but there are some important differences between them. Both have threaded couplings that attach to the threads on the cylinder valves. The coupling leads the gas into the pressure regulating chamber, which is the main body of the regulator. Both regulators have a large key on the front of the chamber which is used to regulate the pressure of the gas going to the welding torch. Each regulator also has two glass covered pressure gauges. One of these (the cylinder pressure gauge) indicates the actual gas pressure in the cylinder; the other (the hose pressure gauge) indicates the pressure the operator sets with the adjustment key. The adjustment key controls a diaphragm in the pressure chamber which regulates the outgoing pressure. And, both regulators have a threaded coupling to which you connect the pressure hose to the torch.
There are two basic differences, however, between the oxygen and acetylene regulators. First, the oxygen regulating diaphragm and pressure chamber are constructed more heavily because of the great pressure under which oxygen is kept in the cylinder. So, naturally, the oxygen cylinder's pressure gauge has a higher reading: it shows oxygen from 0 to 4000 pounds per square inch of cylinder pressure. The hose pressure gauge shows a reading of from 0 to 100 pounds per square inch going to the torch. The second basic difference is that the oxygen regulator couplings for both the cylinder valve and for the hose coupling are threaded with clockwise, right hand threads. The acetylene cylinder is just the reverse, for reasons I will explain.
The acetylene cylinder has counter-clockwise, left hand threads on it to prevent its being put on the oxygen cylinder by mistake. Since both the pressure diaphragm and the acetylene regulating chamber are lighter than those of the oxygen regulator, both would break if they were used for oxygen. Also, it is necessary to have a built-in safety factor for controlling the acetylene pressure: the fact that the acetylene regulator has left-handed threads keeps the operator aware of acetylene's dangerous characteristics.
In addition, the gauges on the acetylene regulator have special markings. The gauge showing the cylinder pressure reads from 0 to 600 pounds per square inch (some also show the cubic feet in volume). The gauge showing the regulated pressure to the torch reads from 0 to 30 pounds per square inch. The area on the dial above the 15 PSI is marked in red as an additional safety warning not to use pressure greater than 15 PSI.
The differences between oxygen and acetylene regulators are built-in safety devices for the operator's protection. They serve as a constant reminder that acetylene gas, when not handled properly, can be dangerous. Some companies even paint the acetylene regulator red and the oxygen regulator green to emphasize the difference. All welding hose manufacturers use these colors for the two hoses.
There are several major manufacturers of oxyacetylene equipment. Just which manufacturer's product you will eventually prefer will depend on the experience you gain with different set-ups.
All the major manufacturers make good products, but each has its own special variations. There are different regulators for heavy or light usage. There are torches for very heavy industrial welding, and light ones for lighter uses. Some manufacturers produce a welding kit that is an ideal beginner's set-up. I started welding with one such kit and, though I have since purchased other equipment, all of my kit tools are still in working order and are occasionally used as a second outfit or as temporary replacements for the newer tools. These kits consist of the two regulators, a welding torch, welding torch tips, a cutting attachment, 25' lengths of double hose, goggles, a lighter, wrenches, and a welding manual.
WELDING TORCH AND TIPS
The welding torch is a two part tool that receives its gas supply from the regulators by a hose. The hand held part of the torch is called the mixer (Fig. 4); the other part is called the torch tip. The mixer has two threaded attachments for the hose: one right hand threaded for the oxygen, the other left hand threaded for the acetylene. The mixer also has two valves to control the flow of gases into the tip. And there is a threaded connection for the torch tip which attaches to the mixer.
Welding torch tips come in graduated sizes (Fig. 5). There are tips suitable for every welding need. Those with very small openings are used for welding lighter gauge metals. Those tips with larger openings are used for welding thicker stock.
All welding tips, regardless of size, are fastened onto the mixer by a threaded coupling. The seating end of the tip and the housing that holds the tip in the mixer are very carefully fitted to one another, so that torch tips can be seated only by a firm hand tightening. Never seat a torch tip with a wrench; this may damage the tip.
Tip openings are cleaned with tip cleaners made of steel wires in graduated sizes. These cleaning wires are hung on a spindle inside an aluminum case that is very compactly made.
There is also the torch lighter (Fig. 6), a hand operated device of heavy flexible wire, which scratches a flint across roughened steel. The sparking flint ignites the acetylene that flows from the torch tip.
CUTTING ATTACHMENT AND TIPS
I have now described all the apparatus required for welding steel or bronze, except for an additional attachment that fits onto the mixer. This is the cutting attachment which fits onto the mixer handle by the same sort of threaded coupling used for the welding tips. The cutting torch is not a necessary item for the beginning sculptor-welder, but it is a very useful tool to own as time goes on.
Excerpted from Creating Welded Sculpture by Nathan Cabot Hale. Copyright © 1968 Watson-Guptill Publications. Excerpted by permission of Dover Publications, Inc..
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