Lathe Feeds and Mechanical Inquiry

The lathe-feed topic will bear a great deal more stirring up. The product of the lathe is of course not determined alone by the feed employed. It may often occur that one using a fine feed will turn out a quicker and better job than one using a coarse feed upon a similar piece of work. We often hear it remarked that no two men will do a job alike. Certainly not.

Still there is but one best way, and where men differ in practice there is something that one can learn of the other. It will generally happen, perhaps, that even in such a case the advantage is not all upon one side, and in some particulars each may learn of the other. The actual exchange of ideas is always mutually profitable, but there is plenty of gab perpetrated, which involves no transfer of mental currency. The man who says the most is not the man who has the most to say.

A machinist “learning the trade”—and that he always is—finds himself in the position of a young man whom a fond father was sending forth into the world to seek his fortune. “My son,” said he, “no one ever embarked in life under more favorable auspices: you have everything to gain and nothing to lose.”

There is everything to gain by acquiring, nothing to lose by imparting, any knowable thing. I have no trade secrets. I hold nothing that I am not ready to impart to whoever asks it. I do not seek, I will not accept any technical knowledge which I may not be at liberty to exchange as I choose. I would not value money that I might never spend. I have been offered the custody of the most tremendous mechanical discoveries (not the Keely motor) upon the condition of profound secrecy, and I have been compelled to decline the honor.

A latheman to become expert should make a study of feeds and exercise his judgment in the choice of them. He should experiment continually. The study of feeds he would find that he could not pursue as an isolated study. The mere changing of the belt upon his feed cone and watching its effect would be but a very little part of it. He would find if he pushed for that he would have immediately to consider the shape and temper and material of the tool used, the mode in which it was held, its height, pitch and distance to reach to the work, the make and strength of the tool holder and the strength and design of the whole lathe, and its comparative merits and deficiencies as compared with other lathes. Then the material upon which he was operating, the way in which his work was held in the lathe, the mode of driving if upon the centers, would all call for consideration.

The art of learning is the art of asking questions. The great mistake in the practice of the art is in the thought that the questions are to be asked of men. They are the very last instead of the first sources of knowledge. Ask your questions of things, and ask persistently, and if you can’t possibly find an answer there then try the best man you know, but don’t try very confidently. Some of the most expert workmen I have ever known have learnt the trade—as far as they have got—without asking a half dozen questions of men.

Many, if not most things in the trade, are to be learned without shaping a question. When we are ready to ask the question it is already answered. I worked a good many years at the trade before I discovered that a washer with a square hole in it could be turned upon a round mandrel. When the idea did strike me, the time of questioning about it was past. When a fellow has to re-sew a belt and asks me whether it is open or crossed, when I want a screw cut like a given screw and he asks me to tell him the pitch, when he asks me whether a piece of square iron can be centered truly in a three-jawed centering machine, he is not learning, he is only dodging the asking of the real question and betraying himself.

When you see a man who has a wide variety of work persistently using the same feed for everything, you may be sure there is something wrong about him. If a man is utterly without pride in his calling, and of course with it is without ambition or hope of betterment, and just wants to fill his time and draw his wages, he will use the finest feed upon the lathe as persistently as he thinks it safe to; and he will use his finest feed simply because there is no finer, just as the man rode third class upon the railroad because there was no fourth class.

What you eat and how you eat it determines your digestion. What ideas you swallow will determine your mental action. One who has hastily and without examination bolted the pseudo doctrine of the irrepressible conflict between employer and employe is in a bad way. He is the middle-feed man in our shops, and few shops are without him.

I would not speak of him with severity, for he is more to be pitied. He is frightened, and has lost his wits. His middle feed is his compromise of what to him is a grave difficulty. He is between two fires, and hopes to dodge them both. His employer must not grumble, and say that he is not doing his best, because it is evident that he could use his finest feed and not do as well. His fellows cannot say that he is rushing things, that he is guilty of the nefarious design of making work scarce, for he still has his coarsest feed in reserve; and so day after day he pursues his way of hopeless and monotonous mediocrity. Oh, I would have to jump up and down and tear around, and smash things, to stir my vital fluids occasionally.

I tried a little experiment on one of these middle-feed men the other day. He has gone now, poor fellow. We have a lathe which has a small cone—three steps—geared to the feed rod, which runs along the front of the lathe. The cone has a gear of thirty teeth and the rod one of forty-five teeth, and I found that they were by design interchangeable, and I thought the idea a good one, as giving the desirable change of feed for some special kinds of work without cost to anybody. I changed these gears, thereby more than doubling the feed of his lathe, and my middle-feed man went right along just the same as ever, perfectly safe and satisfied with his middle feed. The experiment showed me, what I knew very well before, how much the requirements of his had to do with the feed that he used.

I don’t know what kind of bargain is tacitly made when a man is hired to run a lathe. He generally talks beforehand as if he meant to get all that he could out of it. If a man wants to get along in the world, and doesn’t do his best, he is a fool. The proprietor of a shop has an indisputable right to dictate how his tools shall be operated. But dictating feeds is too much like quarreling with the cook. The cook has the game in his own hands and has too many opportunities of revenge. The cultivation of a healthy emulation and hearty esprit de corps is better than too frequent specific criticisms.

Frank H. Richards

American Machinist – March 17, 1883

—Jeff Burks