Rough and Tumble Engineering

by James H. Maggard

A TRACTION ENGINE ON THE ROAD

You may know all about an engine. You may be able to build one, and yet run a traction in the ditch the first jump.

It is a fact that some men never can become good operators of a traction engine, and I can't give you the reason why any more than you can tell why one man can handle a pair of horses better than another man who has had the same advantages. And yet if you do ditch your engine a few times, don't conclude that you can never handle a traction.

If you are going to run a traction engine I would advise you to use your best efforts to become an expert at it. For the expert will hook up to his load and get out of the neighborhood while the awkward fellow is getting his engine around ready to hook up.

The expert will line up to the separator the first time, while the other fellow will back and twist around for half an hour, and then not have a good job.

Now don't make the fatal mistake of thinking that the fellow is an expert who jumps up on his engine and jerks the throttle open and yanks it around backward and forward, reversing with a snap, and makes it stand-up on its hind wheels.

If you want to be an expert you must begin with the throttle, therein lies the secret of the real expert. He feels the power of his engine through the throttle. He opens it just enough to do what he wants it to do. He therefore has complete control of his engine. The fellow who backs his engine up to the separator with an open throttle and must reverse it to keep from running into and breaking something, is running his engine on his muscle and is entitled to small pay.

The expert brings his engine back under full control, and stops it exactly where he wants it. He handles his engine with his head and should be paid accordingly. He never makes a false move, loses no time, breaks nothing, makes no unnecessary noise, does not get the water all stirred up in the boiler, hooks up and moves out in the same quiet manner, and the onlookers think he could pull two such loads, and say he has a great engine, while the engineer of muscle would back up and jerk his engine around a half dozen times before he could make the coupling, then with a jerk and a snort he yanks the separator out of the holes, and the onlookers think he has about all he can pull.

Now these are facts, and they cannot be put too strong, and if you are going to depend on your muscle to run your engine, don't ask any more money than you would get at any other day labor.

You are not expected to become an expert all at once. Three things are essential to be able to handle a traction engine as it should be handled.

First, a thorough knowledge of the throttle. I don't mean that you should simply know how to pull it open and shut it. Any boy can do that. But I mean that you should be a good judge of the amount of power it will require to do what you may wish to do, and then give it the amount of throttle that it will require and no more. To illustrate this I will give an instance.

An expert was called a long distance to see an engine that the operator said would not pull its load over the hills he had to travel.

The first pull he had to make after the expert arrived was up the worst hill he had. When he approached the grade he threw off the governor belt, opened the throttle as wide as he could get it, and made a run for the hill. The result was, that he lifted the water and choked the engine down before he was half way up. He stepped off with the remark, "That is the way the thing does." The expert then locked the hind wheels of the separator with a timber, and without raising the pressure a pound, pulled it over the hill. He gave it just throttle enough to pull the load, and made no effort to hurry ii, and still had power to spare.

A locomotive engineer makes a run for a hill in order that the momentum of his train will help carry him over. It is not so with a traction and its load; the momentum that you get don't push very hard.

The engineer who don't know how to throttle his engine never knows what it will do, and therefore has but little confidence in it; while the engineer who has a thorough knowledge of the throttle and uses it, always has power to spare and has perfect confidence in his engine. He knows exactly what he can do and what he cannot do.

The second thing for you to know is to get onto the tricks of the steer wheel. This will come to you naturally, and it is not necessary for me to spend much time on it. All new beginners make the mistakes of turning the wheel too often. Remember this-that every extra turn to the right requires two turns to the left, and every extra turn to the left requires two more to the right; especially is this the care if your engine is fast on the road.

The third thing for you to learn, is to keep your eyes on the front wheels of your engine, and not be looking back to see if your load in coming.

In making a difficult turn you will find it very much to your advantage to go slow, as it gives you much better control of your front wheels, and it is not a bad plan for a beginner to continue to go slow till he has perfect confidence in his ability to handle the steer wheel as it may keep you out of some bad scrapes.

How about getting into a hole? Well, you are not interested half as much in knowing how to get into a hole as You are in knowing how to get out. An engineer never shows the stuff he is made of to such good advantage as when he gets into a hole; and he is sure to get there, for one of the traits of a traction engine is its natural ability to find a soft place in the ground.

Head work will get you out of a bad place quicker than all the steam you can get in your boiler. Never allow the drivers to turn without doing some good. If you are in a hole, and you are able to turn your wheels, you are not stuck; but don't allow your wheels to slip, it only lets you in deeper. If your wheels can't get a footing, you want to give them something to hold to. Most smart engineers will tell you that the best thing is a heavy chain. That is true. So are gold dollars the best things to buy bread with, but you have not always got the gold dollars, neither have you always got the chain. Old hay or straw is a good thing; old rails or timber of any kind. The engineer with a head spends more time trying to give his wheels a hold than he does trying to pull out, while the one without a head spends more time trying to pull out than he does trying to secure a footing, and the result is, that the first fellow generally gets out the first attempt, while the other fellow is lucky if he gets out the first half day.

If you have one wheel perfectly secure, don't spoil it by starting your engine till you have the other just as secure.

If you get into a place where your engine is unable to turn its wheels, then your are stuck, and the only thing for you to do is to lighten your load or dig out. But under all circumstances your engine should be given the benefit of your judgment.

All traction engines to be practical must of a necessity, be reversible. To accomplish this, the link with the double eccentric is the one most generally used, although various other devices are used with more or less success. As they all accomplish the same purpose it is not necessary for us to discuss the merits or demerits of either.

The main object is to enable the operator to run his engine either backward or forward at will, but the link is also a great cause of economy, as it enables the engineer to use the steam more or less expansively, as he may use more or less power, and, especially is this true, while the engine is on the road, as the power required may vary in going a short distance, anywhere from nothing in going down hill, to the full power of your engine in going up.

By using steam expansively, we mean the cutting off of the steam from the cylinder, when the piston has traveled a certain part of its stroke. The earlier in the stroke this is accomplished the more benefit you get of the expansive force of the steam.

The reverse on traction engines is usually arranged to cut off at I/4, I/2 or 3/4. To illustrate what is meant by "cutting off" at I/4, I/2 or 3/4, we will suppose the engine has a I2 inch stroke. The piston begins its stroke at the end of cylinder, and is driven by live steam through an open port, 3 inches or one quarter of the stroke, when the port is closed by the valve shutting the steam from the cylinder, and the piston is driven the remaining 9 inches of its stroke by the expansive force of the steam. By cutting off at I/2 we mean that the piston is driven half its stroke or 6 inches by live steam, and by the expansion of the steam the remaining 6 inches; by 3/4 we mean that live steam is used 9 inches before cutting off, and expansively the remaining 3 inches of stroke.

Here is something for you to remember: "The earlier in the stroke you cut off the greater the economy, but less the power; the later you cut off the less the economy and greater the power."

Suppose we go into this a little farther. If you are carrying I00 pounds pressure and cut off at I/4, you can readily see the economy of fuel and water, for the steam is only allowed to enter the cylinder during I/4 of its stroke; but by reason of this, you only get an average pressure on the piston head of 59 pounds throughout the stroke. But if this is sufficient to do the work, why not take advantage of it and thereby save your fuel and water? Now, with the same pressure as before, and cutting off at I/2, you have an average pressure on piston head of 84 pounds, a loss of 50 per cent in economy and a gain of 42 per cent in power. Cutting of at 3/4 gives you an average pressure of 96 pounds throughout the stroke. A loss on cutting off at I/4 of 75 per cent in economy, and a gain of nearly 63 per cent in power. This shows that the most available point at which to work steam expansively is at I/4, as the percentage of increase of power does not equal the percentage of loss in economy. The nearer you bring the reverse lever to center of quadrant, the earlier will the valve cut the steam and the less will be the average pressure, while the farther away from the center the later in the stroke will the valve cut the steam, and the greater the average pressure, and, consequently, the greater the power. We have seen engineers drop the reverse back in the last notch in order to make a hard pull, and were unable to tell why they did so.

Now, as far as doing the work is concerned, it is not absolutely necessary that you know this; but if you do know it, you are more likely to profit by it and thereby get the best results out of your engine. And as this is our object, we want you to know it, and be benefitted by the knowledge. Suppose you are on the road with your engine and load, and you have a stretch of nice road. You are carrying a good head of steam and running with lever back in the corner or lower notch. Now your engine will travel along its regular speed, and say you run a mile this way and fire twice in making it. You now ought to be able to turn around and go back on the same road with one fire by simply hooking the lever up as short as it will allow to do the work. Your engine will make the same time with half the fuel and water, simply because you utilize the expansive force of the steam instead of using the live steam from boiler. A great many good engines are condemned and said to use too much fuel, and all because the engineer takes no pains to utilize the steam to the best advantage.

I have already advised you to carry a "high pressure;" by a high pressure I mean any where from I00 to I25 lbs. I have done this expecting you to use the steam expansively whenever possible, and the expansive force of steam increases very rapidly after you have reached 70 lbs. Steam at 80 lbs. used expansively will do nine times the work of steam at 25 lbs. Note the difference. Pressure 3 I-5 times greater. Work performed, 9 times greater. I give you these facts trusting that you will take advantage of them, and if your engine at I00 or I00 lbs. will do your work cutting off at I/4, don't allow it to cut off at I/2. If cutting off at I/2 will do the work, don't allow it to cut off at 3/4, and the result will be that you will do the work with the least possible amount of fuel, and no one will have any reason to find fault with you or your engine.

Now we have given you the three points which are absolutely necessary to the successful handling of a traction engine, We went through it with you when running as a stationary; then we gave you the pointers-to be observed when running as a traction or road engine. We have also given you hints on economy, and if you do not already know too much to follow our advice, you can go into the field with an engine and have no fears as to the results.

How about bad bridges?

Well, a bad bridge is a bad thing, and you cannot be too careful. When you have questionable bridges to cross over, you should provide yourself with good hard-wood planks. If you can have them sawed to order have them 3 inches in the center and tapering to 2 inches at the ends. You should have two of these about 16 feet long, and two 2x12 planks about 8 feet long. The short ones for culverts, and for helping with the longer ones in crossing longer bridges.

An engine should never be allowed to drop from a set of planks down onto the floor of bridge. This is why I advocate four planks. Don't hesitate to use the plank. You had better plank a dozen bridges that don't need it than to attempt to cross one that does need it. You will also find it very convenient to carry at least 50 feet of good heavy rope. Don't attempt to pull across a doubtful bridge with the separator or tank hooked directly to the engine. It is dangerous. Here is where you want the rope. An engine should be run across a bad bridge very slowly and carefully, and not allowed to jerk. In extreme cases it is better to run across by hand; don't do this but once; get after the road supervisors.