COACH-MAKING. 



697 



Coach- jn general are so little aware of this, that the carriage- 

 u:ikmg. maker has often more difficulty in getting his iron work 

 """""""" made perfect, than in executing his own more particular 

 department. The carriage is always made of ash of the 

 strongest growth, and perfectly dry ; the joint* are put 

 together with white lead ground in oil, secured with 

 bolts and iron plates, stays, hoops, and other iron-work, 

 to the weight of from 230lb. in alight carriage to 370lb. 

 in a heavy one, exclusive of axletrees and springs. 



In fact, carriages, as they have been made for many 

 years past, are, in every part, a combination of wood 

 and iron, in order to produce a light appearance ; the 

 workmen being enabled, from the additional strength 

 of the iron, to reduce the dimensions of the wood. The 

 axle-trees are let into a groove in the underside of their 

 respective bars of wood, (technically called beds) in or- 

 der to secure steadiness ; and they are fastened to the 

 wood by iron hoops and bolts. The springs are made 

 fast to their respective bars with screwed bolts, and the 

 fore or under carriage, (that is, the frame work of wood 

 to which the fore wheels are attached,) is secured to the 

 main carriage by means of a strong iron bolt, called the 

 perch boh, upon which the axle of the front wheels 

 turns independently of the hind wheels, thereby enabling 

 the whole carriage to turn with ease, which it could not 

 otherwise do. 



III. Wheel Making. 



\Vhl ma- A carriage wheel consists of the nave, the spokes, and 

 king. the rim. The nave is the centre wooden part of the 



wheel, which is turned in a turning lath, according to the 

 taste of the workman ; and into morticei in this, the 

 spokes are driven which connect it withtherim. The rim it 

 composed of several circular pieces of wood, called felloes, 

 which are bored with holes to admit the outward ends of 

 the spokes ; the spokes being inserted in these holes, and 

 wedged up, and the joinings of the felloes secured from 

 passing one another, by internal connecting pins, called 

 dowels, the wood work of the wheel is completed. 



To secure the nave from splitting, two iron hoops are 

 put round it ; a narrow one at the end having the great- 

 est diameter, which goes next to the carriage, and is call- 

 ed the in-head of the nave ; and a'broad hoop is put 

 round the smaller end farthest from the carriage ; this 

 end is called the out-head of the nave ; and the hoop, last 

 mentioned, projects beyond the nave, in order to protect 

 the end of the axletree of the carriage when running, 

 and in the fore wheel* it also serves the coach-man at a 

 footltep to mount to the driving box or seat. 



The chief difficulty in this branch is the execution of 

 the work, as the angles of the joints are easily found, af- 

 ter which it only remains to draw a circle of the given 

 diameter of the wheel, and work the felloes to it. When 

 the workman, therefore, by experience, is enabled to put 

 his work together in such a way, that, when the wheel is 

 ompleted, all its parts bear equally against one another, 

 the knowledge of his art is acquired ; and, being provided 

 with wood of good quality and well seasoned, he will 

 produce a wheel of strength and durability. The naves 

 are generally made of Scotch Elm, the spokes of Oak, the 

 main stem of small Scotch Highland Oak being prefer- 

 red, and for the felloes ash is reckoned best. 



Each felloe has, at least, two spokes. Sometimes, 

 in place of separate felloes, one piece of wood is bent, by 

 means of steam, into a complete circle for the rim of the 

 wheels. Wheels made in this way are preferable in ap- 

 pearance, but the difficulty of repairing them has prevent- 

 ed their being brought into general use. There are two 



VOL. VI. PART 11. 



kinds of wheels, the conical wheel, and the cylindrical Coach- 

 wheel ; of the former, there are the single dished and J"^""!; 

 die double dished, and of the latter there are the straight ^"Y"~ 

 wheel and the cross dished wheel. These we shall 

 describe : Let a line be supposed to be drawn from the 

 centre of the nave, at the in-head, to the centre at the 

 out-head, and let this line be called the axis of the 

 wheel. A wheel is single dished, when the spokes, 

 being all one length, and diverging outwards from the 

 carriage, form, with the axis of the wheel^ acute angles 

 towards the out -head. A wheel is double dished when 

 each spoke alternately forms, with the axis of the wheel, 

 a more acute angle towards the out-Head than the others ; 

 all of them, however, at the circumference, terminating 

 in one plane at right angles to the axis. The straight 

 wheel is so called when the spokes stand perpendicular- 

 ly to the axis in the same plane. The cross dished 

 wheel derives its name from each two alternate spokes, 

 forming, with the axis, an isosceles triangle, the spokes 

 being alternately joined nearer to the out-head and in- 

 head of the nave, but all of them terminating at the cir- 

 cumference in one plane, inseriectmg the axis between 

 the roots of the spokes. For the properties of the diffe- 

 rent kinds here described, see WHEEL. 



IV. Stnillt Work. 



There is great variety of smith work necessary in ma- s m ; t h 

 king a carriage, and as much dependence is put upon the work. 

 iron work : it must be not only of the very best quality, 

 but worked in the best possible manner ; upon these ac- 

 counts, ordinary bred smiths are not, without a good 

 deal of practice, fit to be employed by coach-makers, 

 except in the coarser parts. In order to obtain as much 

 perfection as possible in the execution of this branch of 

 the work, it is subdivided into particnlar departments : 

 some workmen being constantly employed in making 

 springs, others at the axle trees, others at the steps, 

 some at the iron work upon the wheels, some at the dif- 

 ferent plates and stays for new carriages, and others at 

 repairs upon old work of all kinds. The springs 

 ought to be of steel, of the best quality, well worked 

 and properly tempered, which is the chief art of the 

 spring-maker. In spring-making there is a considerable 

 nicety required in proportioning the thickness and lengths 

 of the different plates, giving them an equal temper and 

 proper set, in order to produce a regularly increasing re- 

 sistance to any weight that may be put upon them. It 

 is by these means that a carriage can be made equally 

 easy to be rode in with one person only as with four or six. 

 The axletrees ought to be built of different bars of iron, 

 laid along side of one another, and well welded together ; 

 for this purpose the tire which comes off old wheels is 

 preferred, and the thinner it is worn down so much the bet- 

 ter, as a greater number of plies are necessary, thus recei- 

 ving a better mixture of metal, and, of course, greater uni- 

 formity andaverage strength. The finishing of the axletrees 

 ought to be done with the greatest possible accuracy, as 

 much of the ease of draught depends upon that circum- 

 stance, and as the greatest part of the noise made by car- 

 riages, when in motion, proceeds from the axletrees and 

 boxes not having been properly fitted to one another. A 

 considerable degree of correctness is necessary in making 

 the footsteps, the opposite legs requiring to be of exact- 

 ly equal lengths, the joints solid and smooth that they 

 may fold with ease, and at the same time not be liable 

 to fail soon or get loose. The variety of iron plates 

 and fastenings requisite for a carriage is so great, that 

 it would exceed our bounds io describe them all : 



