A practical treatise on coach-building historical and descriptive

by James W. Burgess

When the wheel is so far progressed with it is laid on the ground, and the felloes are ranged round it in the order they are to be fitted. It is of the greatest importance that the holes should be bored in the felloe in an exact radial line from the nave; if this is not done, the spoke will have to be strained out of the straight line in order to get it into the hole; this will put an undue pressure upon it, and it is very likely that before the wheel has been long in use the spoke will break off short at the felloe. The exact position of all the mortises and joints should, therefore, be worked out on a full-sized drawing, and this being accurately done, there will not be much danger of going wrong. As the construction of a wheel is somewhat analogous to the arch, it is considered that by giving the felloes a number of joints the strength of the wheel is very much increased. Whether this be so or not must be left to the theorists to determine, as we have no trustworthy results from the various experiments under this heading.

The number of felloes in a wheel is decided by its size and number of spokes, two spokes being driven into each felloe. For an ordinary-sized brougham the felloes should be seven in number for the hind wheels, and six for the front wheels, or fourteen and twelve spokes respectively. For the purpose of connecting the felloes, a dowel or pin is cut on the end of one of them, and a corresponding hole bored on another, and they are fitted together; in common work holes are bored in each felloe, and an independent pin of hard wood or iron fitted into them. There is less time and labour consumed in this latter method; but the felloes constructed on this plan are not very reliable, and their weakness is soon shown by what is known as “dropping,” which is simply caused by the wear and tear to which wheels are subject working the dowels in the holes and enlarging them (the holes), and destroying the truth of the joint, which loss is soon discovered by the play or freedom given to the felloes allowing them to slip out of their place. But it must be borne in mind that this defect is just as liable to take place in felloes put together in the other way if the holes are not truly bored, and the joints are not well fitted.

The following directions as to putting on the tires are given in the “Coachmaker’s Handbook,” an American work:—

“First examine the wheels and see what condition they are in for the tire, so that we can determine what draught to give them. See if the felloes are drawn snug on the shoulder of the spokes, and how much open there is in the rim; for instance, one set we will suppose to be 1½-inch felloe, open ³⁄₁₆ of an inch, give a good ¼-inch draught; 1⅜-inch felloe, ³⁄₁₆ open, just ¼-inch draught; 1¼-inch felloe, ³⁄₁₆ open, ³⁄₁₆-draught, and so on.

“Now in determining what draught to give the above wheels, we supposed them all to be good, sound, hard, hickory felloes; if the felloes are of soft timber just give them a trifle more draught. If the wheels should be above ¼-inch dish, the felloes would want only one-half the opening, but give them the same draught as the above. In running the tire, lay all the above tire in sets on the floor, roll the wheels on them, and allow 1 inch for taking up in bending; then mark the end of the nave with chalk, 1, 2, 3, 4, &c., and the tire with a sharp cold chisel mark I., II., III., IV., &c. Then straighten on a block set up endwise about 2 feet high, a little concave or hollow in the centre, letting the helper strike while the smith manages the tires until the kinks are all taken out of them. Then bend one end a little, so that it can be got into the machine, and take pains to get them as round as possible.

“In running the wheels with a ‘traveller,’ a wedge must be driven in one of the joints of the felloe for the purpose of tightening the other joints in the rim. Then get the length of the felloe, and in running the tire cut it ⅛ inch shorter than the rim measures. In this explanation we are supposed to have steel tire, and we have a kind of steel tire now that is very high and difficult to weld, and there are many smiths that will profit by this lesson if they attend to the precaution we give. This tire steel will not stand as heavy heat as even cast steel, and if it is over-heated in the least it will crack or break in two while hot.

“There is one peculiar fact connected with it that we find in no other kind of steel, and that is this: it is apt to slip, however good the heat, and to obviate this, after scaffing the ends down to a sharp edge, make a rather sharp lap, and while hot take a sharp-pointed punch and punch a hole nearly through both laps, and drive in a sharp pin made of ³⁄₁₆-inch steel wire and ½ inch long. This will not show on the outside of the tire when on the wheel, neither does it weaken the tire like a rivet. We have often seen tires broken where the rivet went through.

“In welding, first have your fire perfectly clean, the coal pretty well charred, and the fire hot, but rather small, for the smaller the fire, if hot, the less it will waste your tire each side of the weld; have the borax charred; put a little on the weld while hot, pull the fire open with the poker and place the lap in the hottest part; roll a few pieces of coked coal on the weld, blow steadily, carrying your tire back and forward through the fire, or stop the blast a moment until the lap is heated alike all through; take it out and weld with hammer and sledge. With this precaution you will never fail getting a good welding heat, and need not upset your tire before welding. If your tire is upset before welding it makes the lap so much thicker that before it can be heated through alike there is a liability to over-heat, and waste away the tire on each side of the weld.

“In laying the tires down the heaviest should be laid at the bottom, and levelled with brick, so that the tire will rest permanently on every brick or bearing, and the rest laid on top the way they will fit best, to prevent warping the tire in the fire. A level stone should be used to lay the wheel on when the tire is put on. If the tires do not get warped in the fire do not hammer them at all, without there are some kinks left in the tires in fitting them; avoid hammering if possible, for it marks the tire; cool off, gradually pouring the water on out of the spout of a tea-kettle until it shrinks enough so it can be taken up; then roll it in soap-water to prevent it from hardening, until it is so cool that it will not burn the felloes, truing up while the helper is rolling it in the water with a mallet covered with thick leather at both ends; let the third person take the wheel and finish truing the tire with a leather-covered mallet; while it is so hot that you cannot bear your hand on it the felloes move easily under the tire, and it should not be moved after it has cooled off if it can be otherwise avoided, for this reason, when the tire gets cold all its roughness and imperfections become embedded in the felloe.”

“The tire once moved will move the easier next time. After the tires are all on examine the wheels, and see if there are any crooked spots in the tire that do not set down to the rim; should there be any, heat a short piece of iron and lay on the tire, it will soon heat it enough to burn the felloe, but take it off before that time, and rap it down with a hammer. It is a bad practice to heat the tires on a forge as some do, for in truing them in fitting we have to bend them cold, and if heated on the forge and one place red hot, you will often find there a short crook edgewise. If some of the wheels are dished more than the others, put them on the off-side of the carriage. Never take a tire off if it can be avoided, without it is so loose or tight as to spoil the wheel when run.”