£20 CARAND HOW TO MAKE IT !

The First Article of a Series Describing the Construction of an Ingenious, Simple Well-designed Three-Wheeler, which May be Built for even less than £20. Its Annual Tax  is Only £4, and it is Capable of 50 Miles an Hour. Petrol Consumption is over 65 Miles per Gallon, and it may be driven by any reader over 16 years of age ! The Illustration Below Indicates its Really Attractive Lines. Any Unskilled Amateur Can Make it With Ordinary Tools. By F.J. Camm.

IF you have ever thought of the possibility of building for yourself a small runabout car, you have probably dismissed the idea as being outside the bounds of possibility for amateur construction, or as requiring a heavy initial outlay and the possession of tools and equipment usually associated with the factory. Therefore, I wish to disabuse your minds on these various points at the outset.

It is probably not known to many of my readers that several thousands of midget cars are built. in America annually, and so intensely enthusiastic is the movement over there, that race meetings are held all over that vast country practically every night on the various dirt and hard tracks. There are hundreds of midget car clubs in America and Canada, and a few in Australia, and the rules of membership and of the various midget-car competitions are firstly that the car must be amateur built, and, secondly, that the engine must not exceed a specified cubic capacity. Midget-car racing has 'become, in fact, a craze, and the sport bids fair to become popular in England.

Note the Simplicity and Really attractive lines of this fast baby Car . You can build it !

Floodlit Racing TracksT h e American midget-car events draw enormous crowds and after dark the  tracks are floodlit. It is a fascinating sight to witness these tiny vehicles, most of which are capable of speeds of over 60 miles an hour hurtling round the track and performing amazing evolutions demanding little of the skill which is required o drive more orthodox cars round Brooklands.These tiny cars, however, are not built merely for racing purposes, and vast numbers of them are used for ordinary touring purposes. They have the great advantage, of course, of low taxation, require a minimum amount of garage space, are cheap to run (the petrol consumption is at least 65 miles to the gallon), are cleaner than motor cycles, and they have the added advantage of providing weather protection, which a motor cycle does not. They can also be used for touring along the narrow lanes and picturesque by-ways, which would be impossible for larger cars, and above all, they are perfectly safe.

Simple Construction;The greatest advantage, perhaps, is that they may be built for as small an amount as £15, depending upon the number of refinements which are fitted. Given a motor- cycle engine of the air-cooled type of from 250 c.c. to 600 c.c., a motor-cycle type of countershaft three-speed gearbox with integral clutch, and three wheels, and you have the material for building a midget car. The veriest amateur possesses the ability to construct one. Many years ago the cycle- car movement in England was extremely popular, and as with radio, there was a considerable number of amateurs who built them. No doubt owing to the unreliability of early engines a n d the difficulty of obtaining the requisite parts, the midget-car movement fell by the wayside. Nowadays, however, there is a plentiful supply of material. Motor-cycle engines of the required capacity can be picked up quite cheaply from garages and other firms who specialize in spare parts. So, too, can gearboxes, whilst the wheels can be purchased new for a very small sum. Many years ago 1 designed a similar small car to that forming the subject of the present article and marketed it, and it proved extremely popular. You require a motor-cycle engine of either the side or overhead valve type of not more than 350 c.c. for the design here given, and as 1 horse-power is approximately equivalent to 100 c.c. the power range required is from 2 1/2 to 3 1/2. If you fit a 2 1/2 horsepower engine the top speed would be an easy 40 miles an hour, whereas with a 350 c.c. engine the top speed would be in excess of 50 miles an hour. Naturally, the overhead-valve engines will be the faster.

Why a Three-Wheeler was ChosenI will anticipate the reader's question of explaining why a three-wheeler has been chosen in preference to a four wheeler. In the first place the legal definition of a three-wheeler is that it is a motor cycle! As such, it comes within the same taxation class as a motorcycle and sidecar. Secondly, it is cheaper to build, for the excellent reason that there are only three wheels and three tyres, instead of four wheels and four tyres, thirdly, the three-wheeler dispenses with the need for a differential gear. Fourthly it is easier to build and has less working parts. The annual tax is £4 only. If you add to these advantages the fascination of building it, and finally of using it on the road you have the entire case for the tiny car.

Detailed Blueprints will be Issued for a Nominal sum.

 Legal Requirements In the absence of proved designs, the beginner may make expensive mistakes. There are the legal requirements, for example, which stipulate that brakes must apply to each wheel, and that there must be an independent hand-brake; the head lamps, in order to satisfy the Lighting Act, have to he mounted at a certain height from the ground and not more than a certain distance in from the extreme outside line of the vehicle. The number plates and the figures and letters there on, must be to legally prescribed dimensions, and a silencer must he fitted. The machine must not be noisy. Those are just a few of the legal requirements. The mechanical requirements are a little more detailed. We have to bear in mind the loading per horse-power so that the engine does not labour. The steering angle needs to be worked out for wheel clearance, and provision must be made for cooling the engine. The gear ratios must be carefully selected, so that the engine is enabled to rev. at its peak revolutions in order that it may develop maximum power. The chassis must he free from whip, otherwise there would he frequent breaking of chains and undue wear on the transmission and tyres. The suspension System needs to he just right in order to absorb road shocks. The centre of gravity needs to he accurately disposed, so that the machine is stable and does not turn over, and the driver's seat needs to he disposed approximately midway between the two points of road support. Hence., the amateur who endeavors to design his own car finds this array of technical and legal considerations disconcerting.

The Problems Solved for YouIn the design here presented the problems have been solved for you. Our £20 car complies with all of the legal requirements, and it is technically sound. In later articles dealing with its construction I shall show you photographs of the various stages, and photographs of the car under test. Additionally, we shall sell detailed blueprints and an announcement will be made when they are ready. All of the constructional details, however, including dimensioned drawings will be given in this series, thus enabling the reader to build the car. The blueprints will be issued to those who are unaccustomed to laying out the various parts from scale drawings.

A Driving Licence Another question which will arise, in the mind of the reader who is under 17  years of age (the minimum age for which a driving licence for a car-owner is issued), is whether he is entitled to drive this three-wheeler within the meaning of the Act. Anyone over 16 years of age may drive a motor cycle, so the age limit is 16 years. If you are over 17 years, you will apply for a  car.driving licence in the ordinary way. If you have not held a driving licence before, it will be necessary for you to Pass the driving test; for details of this you must apply to the local County Council Offices, when a provisional driving licence will he issued to you. You will have to carry the "L " plate and be accompanied by an experienced driver. As, however, the latter can easily be accommodated pillion-passenger fashion, there is no difficulty here, although I recommend the beginner to teach himself to drive in private grounds. No doubt permission can be obtained locally for this.

Driving the CarYou will find that you will be able to drive the car within about five minutes, after you have become familiar with the operations of starting the engine, accelerating, changing gear, and braking. Actually it it's much easier to drive than a motor cycle. I shall confine my remarks this month to a general description of the design, so that the reader can collect together the necessary material. An inspection of the plan and side elevation, Figs. 1 and 2, indicate the racy lines of the body. The engine is mounted behind the driver's seat and the, gearbox, of course, behind the engine. You will require any good secondhand motorcycle engine of the type and power previously named, and a three-speed gearbox capable of transmitting the power of the selected engine. For example, you must not fit a gearbox from a 250 c.c. engine, if you are using a 350 c.c. engine, although it will be in order for you to use a gearbox which has been used in conjunction with a 350 c.c. engine on a 250 c.c. engine.

The GearboxThe gearbox must be of the countershaft type with an integral clutch, and later I shall show how to calculate the size of sprocket required on the rear wheel in order to obtain, the correct gear ratio. You will also require a silencer of the type fitted to 7 h.p. cars if you desire the engine to be extremely silent, otherwise the ordinary motor-cycle style of silencer will suit. I cannot, for obvious reasons, prepare designs suitable for all of the engines available, but as the only thing which is affected is the method of mounting, the reader will experience no difficulty in obviating this. The kickstarter will, of course, need to he extended by means of a piece of tube so that it protrudes outside the body. It will then he carried a starting handle, and placed under the cushion of the driving seat when the car is started. The wheels are of the light motorcycle type, having internal expanding  brakes operated from a quick pedal, whilst the chassis and body consist of ash members and three-ply respectively. 

The Car Controls CarControls are used, that is to say, there are the usual three pedals, namely (from right to left facing the front of the car), accelerator, brake, and clutch. The steering wheel is centrally disposed, since this is a monocar and not intended. for passenger carrying owing to the low power. The radiator in front is, of course, a dummy; it is made by overlaying pieces of three-ply wood and picking it out in a different colour to that of the body colour. Two doors are fitted so that entry to the driving seat can he effected from either of the near or off side. A motor-cycle sidecar hood is used, whilst the mudguards are of the motor-cycle type.These have the advantage that they move with the wheels and thus do not throw mud when locked over as does an ordinary car. 

Accessories Required The windscreen is one of the Auster aerotype as fitted to small aeroplanes and some sidecars, whilst the steering wheel is of the Bluemel type. The tool-box, number-plate and tail-lamp are combined. Ackerman steering is used, enabling the car to be turned within a very sharp radius since the wheel base is only 5 ft.

in. The overall length being only 9 ft., the car may thus he comfortably stored in the space normally required for a cycle and sidecar. The total weight of the vehicle will be not more than 280 lb. I have estimated that the total cost of the material will be approximately £18, and if the reader happens to strike bargains in his purchase of the various parts, it can be made for less than £10. For this particular car 1 have selected the Blackburn 350 c.c. side-valve engine, but, of course, the reader will endeavour to obtain from the sources mentioned a second-hand car engine and gearbox. Just a word about the petrol consumption; it will work out, with a 350 c.c. engine, at 65 miles per gallon at least, whilst the oil consumption should be in the neighbourhood of 2,000 miles to the gallon. I shall, of course, be pleased to answer any questions  which readers care to me provided they enclose the Query Coupon and a stamped and address ed envelope.  these queries should be confined to the present design,  and I make the offer so that who are able to follow the present illustrations and who wish to proceed with the work in advance of publication of the scale drawings next be able to do so. I want make it clear, however, that I cannot, for obvious reasons, undertake to vary the design to suit individual needs. For example, some readers perhaps prefer to make a four-wheeler; 1 cannot undertake to prepare the many special diagrams which would be necessary to enable them to do so. I shall he quite willing to advise readers regarding suitable engines, gearboxes and materials; to advise them on the lighting question and passing the driving tests. I shall also be pleased to indicate sources of supply for the various parts. Here I would advise the reader to study the advertisement columns of papers like the Practical Motorist (3d. every Friday), particularly the Classified Advertisements. They may thus be able to pick up reliable second-hand gearboxes quite cheaply. A word of warning is necessary, however : make quite sure that any engine you purchase locally is in good condition, for it is just possible that some of the parts have

been sold as spares, and the engine is therefore not complete. If the manufacture has been discontinued, you may experience difficulty obtaining replacements and  they will thus have to be specially made which can be quite costly! 

The  Second Article on this Remarkable Car, Specially Designed for Readers of Practical Mechanics, will appear next month. Order your

copy now !

383   Page D3                              NEWNES PRACTICAL MECHANICS                 April, 1936  The Engine  And now regarding engines. Readers apparently have experienced no difficulty in obtaining offers of second- hand motor-cycle engines and gearboxes at prices varying from 20s. to 30.s. The engine which I have selected is the 350-c.c. side-valve Blackburne, and I am using the well- known Albion gearbox, to the manufacturers of both of which I desire to tender my thanks

for their co-operation in placing units at my disposal. An engine which is eminently suitable for this car is the unit-constructed New Imperial engine which also has the gearbox incorporated. Thus, in the one unit you save yourselves the trouble of having to make two mounting plates if you can call simple metal-work a troublesome operation. It isn't really.  Another question which has produced a volume of correspondence is that concerning the steering

system. I show herewith photographs of the type of steering which I have used. This is similar to that which was fitted on the Carden car, a popular light car which was on the market a few years ago. The great advantage of this system is that it dispenses with leaf-springs, which are somewhat expensive. It will be seen that the steering heads are mounted between the springs, which in themselves absorb the road shocks ; no other form of additional front suspension is necessary.

Type of SteeringA further advantage of this type of steering is that it eliminates the need for a geared steering box such as would be necessary on a heavier car, but quite unnecessary on a light vehicle of this description. Thus, it, will be appreciated that direct steering is employed. It is easy to make, and satisfactory in every way. The front axle merely consists of two pieces of angle iron which can be purchased locally, and which are bolted direct to the chassis members. Nothing could be much simpler than that. I shall give detailed drawings, of course, so that the reader can make up the steering system himself, although he will need to purchase the hubs and rims. Complete wheels will be supplied by the British Hub Company, whose address readers may have on application. It will be seen that the internal expanding brakes are incorporated in the hubs. If you are skilled at wheel building (1 shall give instructions on how to assemble and true the wheels) the cost is very low. I have made arrangements with a manufacturer to supply the steering heads to our readers for a nominal sum, although, of course, they can be cut from the solid if it is desired to save even that expense. But it is not essential that the type of steering illustrated should be used; you may use, for example, the front axle assembly of an Austin " 7," provided that you are able to purchase also the steering box, and the semi-elliptic front springs. These are quite easily mounted by means of the shackles, as on the Austin "7". It is possible to pick up a complete front axle and assembly quite cheaply from the car breakers.

The First Article on the construction of this ingenious three-wheeler appeared last month.  Many hundreds of readers have all ready commenced construction and we have received an enormous amount of correspondence. As stated last month this car can be built for even less than £20, its annual tax is only £4, and it is capable of 50 miles an hour. It may be driven by any reader over 16 years of age,   and its petrol consumption is over 65 miles per gallon.  Best of all, it may be built by any amateur, for the construction has been simplified to avoid skilled fitting, turning,

and brazing.A further article will appear next month.                                                                                      By F.J. Camm

I commence  this month by disposing of some queries I  have received. As these queries are of a general character, I shall thus arrest the pen of other correspondents who may wish to ask similar queries.Firstly, regarding the blue prints. These will be ready  in a fortnight's time and will cost 10s. 6d. the set of four sheets. This may seem rather a lot of money, but they are being produced for the convenience of readers and the work entailed in their preparation is heavy. It will also be appreciated that the demand for them will be comparatively small, and it is impossible therefore to produce them cheaper.Those readers who wish to proceed with the construction in advance of the publication of further details will, if they purchase a set of  blueprints, be enabled to do so. Which brings me to another question which I have received from many readers. I cannot send drawings and details through the post in advance of publication The preparation of separate drawings and sketches and descriptions involves, unfortunately, more time than I have to spare, and queries should be confined to materials, choice of engine's, gear-boxes, etc.

Conversion to a Two-seaterAs I anticipated I have received shoals of letters from those who wish to convert the design into a two-seater. This I do not advise, nor do I think that anyone can   reasonably expect to build a passenger carrying vehicle for £20.This car has been designed as a monocar, and one must draw the line somewhere. Suppose, for example, I altered the design so that it could be used as a passenger-carrying vehicle ; this would mean that the whole structure would need to be strengthened, would be considerably heavier, require a more powerful engine, involve a higher insurance premium, need a heavier gearbox, and so on. Moreover it would invite queries

as to how the design could be amended to carry a third passenger, and even a fourth. Those readers who are minded to do so, can easily adapt the designs here given. I had in mind when producing the designs for this car a vehicle as speedy as a motor cycle, but with the added advantages of weather protection. 1 also had in mind economy of construction and low running costs, and set myself the limit of £20. Deviation from this along the lines which so many readers have been kind enough to suggest would bring the cost of materials alone up to £30 or £40, and for this figure you can purchase an excellent second-hand three or four-wheeled car.

 

Page D4

                                                                 The Rear Wheel For the rear wheel 1 have selected one of the quickly detachable wheels with knock   through spindle as fitted to the Norton and Rudge - Whitworth motor cycles; thus, in the case, of a puncture in the rear tyre, the rear, wheel can easily be removed by   uncoupling the rear chain and knocking out the spindle. The rear members which carry the front wheel are made of wood ; if you are a skilled metal-worker you will, of course, braze up a pair of rear  forks. But wood is quite satisfactory, and easy to work. I am aware that some of the methods  employed in this car are not those used by car manufacturers, but I have had in mind all the time the amateur who has only a few tools. The methods I have employed I have found from experience to be quite satisfactory.For the rear suspension I have used tension springs. These can be purchased locally, and springs of the type used in the front forks of motor cycles will suit. It will be noted that as the rear members are not pivoted on a centre coinciding with the centre of the gearbox sprocket a jockey sprocket must be fitted to compensate for the varying chain tensions.

List of MaterialsSeveral readers have asked for a list of materials, but it is obviously not possible to give this in complete  form because each reader will be using a different make of engine and gearbox. The drawings given this month, however, will enable each

 

 

Page D5                   390          NEWNES   PRACTICAL  MECHANICS                      April, 1936reader to get together the neccssary components. If You have not yet commenced construction, the first thing to do is to get together an engine, gearbox, three wheels, and the front axle. From these components you can erect the chassis, leaving the superstructure until last. The chassis consists of 4 in. x 2 in. ash bearers, and the cross-members are of similar material. Many readers have asked about the cooling system. An opening is left behind the driving seat, as can be seen from the side elevation, so that an air scoop can direct a current of air straight on to the cylinders. This is simple and certainly efficient, for the engine keeps just, as cool as it would do if mounted in the frame of a motor cycle. Observe that the engine and gearbox are carried on engine plates, bolted between the two main members by means of long bolts with suitable distance tubes for location purposes. In order to brace the two rear members and keep them in alignment a long U bolt with angle piecesbrazed at each corner are used, and the rocking members which carry the rear wheel are covered with a washer plate  at the rear extremities ; bushes are placed through to suit the rear-wheel spindles. A detail of this is shown. The petrol tank can conveniently consist of a standard petrol tin.

LubricationLubrication is by means of the pump incorporated with the engine and which merely needs to be coupled up with a small oil tank with a tap soldered into the bottom. This is conveniently mounted through one of the bearers as shown. Mild steel angle brackets could be used to connect the various wooden members together.I have shown the position of the steering and the wheels dotted. but it will be appreciated that the position of the front wheels is provisional only, and will depend upon the type of front axle which is employed. Scale drawings of the axle will be given next month, together with details of the body, seating, and finishing. The screen, as I mentioned last month, is the id Auster type, and steering wheels can be purchased from Bluemels. I shall also include next month actual photographs of the completed car.

The whole of the wooden structure forming the chassis will be apparent from the side and plan views. In selecting the wood, insist upon straight-grained material free from knots and shakes. Ash must be used no other wood is suitable to resist the stresses imposed by the engine. You will save yourself a lot of disappointment by adhering to the specification, and using ash. Most coachbuilders will supply it or get it for you.Wherever possible use bolts. Where wood screws are essential use a small drill to give a leading hole, and dip the point of the screws in vaseline before inserting them. This will prevent rust and make it easy for the screws to be removed. Ash is a hard wood, and any attempt to force a screw home will result in a. mutilated head and a screw which cannot be removed. Where two parts are to be screwed together the top part should have a clearing hole so that the head of the screw can draw the two parts together.Croid or Seccotine are admirable as glues. Where a large surface is to be covered the wood should first be warmed and the glue itself heated in hot water to render it more fluid. After, the two parts are glued they should be placed under pressure for several hours until the glue has set. When using a bradawl make sure that you insert the blade with its cutting edge at right angles to the grain. This will avoid splitting. Use coach-maker's panel pins and oval section brads for nailing purposes. Such should be at least 3/4 in. long, otherwise they will vibrate loose. Where possible use Whitworth or Camount B.S.F. bolts. Do not use stove or gutter bolts as the threads are not sufficiently accurately cut and the nuts will vibrate off. Locking washers should be used under the nuts securing the engine and gearbox plates. The bolts should be of the castellated type  and split pins must be used to secure the nuts.Metal straps should be of 16-gauge mild steel plate of the bright rolled variety. Tinned iron  is unsuitable; for the spacing and distance tubes use bright drawn steel tube of 16 gauge ; the ends, of course must cut square, and the

tubes should be a reasonable fit on the bolts to prevent the latter from bending.

n this Article, The completion of the Engine and Gearbox Mounting, Steering, and Suspension is deal with.    By F. J. Camm

I SHOW this month photographs and drawings of the chassis in various stages, from which the reader will be able

to complete this portion of the work. Obviously, certain of the details will need to be varied as to measurement according to the engine and gearbox used, but the shape of the parts will, of course, remain the same. My drawing relates to the 350 c.c. Blackburne engine and the Albion gearbox. In order to save readers trouble, the address of the former is Burney & Blackburne, Ltd., Atlas Works, Bookham, Surrey, and the latter, The Albion Eng. Co., Ltd., Upper Highgate Street, Birmingham, 12. The hubs for the two front wheels are obtainable from The British Hub Company, Ltd., Weaman Street, Birmingham, 4. When writing to them, mention the name of this journal so that they will be able to identify the parts in question.The Steering HeadI have received quite a number of letters from readers who anticipate that they will have difficulty with the steering head. Accordingly, I  have made arrangements with manufacturers, for these to be supplied complete and ready for use and for a nominal sum; I have also made arrangements for my car to be on exhibition in some of the leading   London stores, so that readers may man inspect it and check tlicir construction against mine.This month I deal in detail with the steering. It will be noticed that  the steering heads have top and bottom pines on which are placed compression and snubber springs , respectively. These two pins are coupled with 3/16in.  angle

iron. The bottom angle iron is bolted to the  two main chassis members by means of bolts and distance pieces, whereas the top bar of angle iron is anchored to the sides of the main   members, by means of pieces of  tubing flattened at each end and bolted in position. Each end will, of course, need to be flattened and bent  to the required angle, so that the parts fit snugly.   They act as tie rods and resist the rocking motion which might  result when the brakes are applied.

.The Engine PlatesThe two transverse cross-members at in front of and behind the engine and gearbox are scoured by means of rods screwed at each end

Page E2                       May 1936                 NEWNES PRACTICAL MECHANICS              443     

Drawings for these various bolts are given, as well as for the engine plates. These are made from 3/16in. mild steel, and the photographs show their location. It will be seen that one long transverse rod passes through the, front engine plate, and others behind the engine and behind the gearbox. The engine and gearbox sprockets are aligned and located by means of pieces of steel tubing which pass over the bolts, washers also being placed at each end, where they abut with the main wooden chassis members. The washers will prevent the tubes from biting into the wood and permitting movement.

A Matter of Alignment It will be appreciated that the driving sprocket on the engine shaft must be in exact alignment with the inner gearbox, and that the outer sprocket on the latter must align with the gear wheel on the rear wheel. The distance pieces (tubes) on the engine bolts securing the engine to the chassis should be cut so that this alignment is secured. I stress this point because if the alignment is out the chains will run off. The gearbox, it will be seen, has two short studs in the top of it, and

these pass through a piece of   3/16in. mild steel with long holes (to permit of front chain adjustment as with a motor-cycle) and which bridges the two gearbox plates. By locking the nuts after the chain tension has been adjusted (the chain should be allowed to sag for at least 1/2 in.), this plate will also secure the gearbox.                          Long Bolts, Distance Pieces, etc. Notice the position of the long bolts, distance pieces, and washers which secure the rear suspension, and observe also that two plates pass outside the body at the point where the rear engine plate meets the gearbox cradle plate. This is a somewhat lengthy description of what is in reality a straightforward piece of metal working. If you have not the dies and screwing tackle, 1 can let you have the address of an advertiser who

will be able to supply you with the parts already out to shape and length. Last month I gave one method of anchoring the rear wheels to the rear  forks.

Page E3   

This month I give an alternative arrangement consisting of a flat piece of 1/8-in. or 3/16-in. mild steel plate clamped to the rear forks by means of three bolts. Either method will suit. , The method given this month has the advantage that it shortens the amount of wood required. I show in one of the photographs the rear suspension attached. It will be appreciated that metal ears will be required for the forward end of the spring to attach them to the spring anchorages and that at the rear suitable spacing tubes and washers will be necessary to enable the springs to take up varying angular positions as the suspension comes into play.

The Tracking RodReverting now to the steering system and front axle, it will be observed that the two arms on the steering head are coupled by means of a track rod, each screwed end of which passes through an eye attached to each arm.  A drawing is given of these eyes. Steering is effected, as clearly shown in one of  the diagrams, by means of a coupling rod, which by push-and-pull motion imparted by the movement of the steering wheel, turns the wheels to each lock. This coupling rod has, of course, turned down ends which are either screwed and nutted or drilled for a washer and split pin. The turneddown ends will also need to be set to the requisite angle, that is to say,one end passes vertically through the steering arm on the steering head, and the other will need to be bent to coincide with

the angle of the arm on the end of the steering column.The Steering ColumnThe latter, as shown in Fig. 7, passes through a hole in the wooden  member securing the two front ends of the main chassis members and has looking collar secured by a tapered hinge. The driver's end of the steering column will eventually he secured to the dash by means of the bracket provided, and will have a similar locking collar to prevent end movement of the steering column. The push-pull steering rod can be attached to either the near side or the off side steering arm.The track rod should have a suffient length of screwed portion at each end to enable the wheels to be toed  in, that is to say, the distance between the wheels at the forward end should be about  3/16 in. less than the distance  between them at the rear. By means of the nuts on each side of the eye, this distance can be adjusted to a nicety. The Brake Pedals  The three brake pedals are made from plate or can be purchased. They are secured to a, rod passing through the two main members and are spaced  means of pieces of tube passed over the rod. A detail of the method of fixing is given.

 Page E4                     May 1936                 NEWNES PRACTICAL MECHANICS              445  

The length of the steering column, which may be of 1-in. steel tube 20 gauge thickness, will depend upon your height. Before cutting it off  to length, sit in the chassis and estimate the length. The steering wheel may be purchased from Messrs. Bluemels, Ltd., Wolston, near Coventry, and should be at least 12 in. in diameter. Although I have arranged for central

mounting of the steering wheel, there is no objection to mounting it to one side. This arrangement of the steering is simple, eliminates the need for elaborate fitting, and perfectly satisfactory.In one of the illustrations 1 show the long U-bolt which connects the rear forks and keeps them in alignment. When this is attached and the rear spindle locked, the rear unit becomes a rigid structure.

Engine and Number PlatesThose bolts which secure the engine and gearbox  rear suspension and rear forks should for preference be fixed with castellated nuts, and be drilled for split pins. This effectively prevents the nuts from working loose and hence obviates risks of lack of chain alignment.A word about making the engine and other plates: chalk over the surface of the steel and copy the sizes from the diagrams and lightly centrepunch round the outline. Then drill a series of holes, breaking into one another outside this outline and file up to shape. Notice that you require two of each different shape of  plates. When drilling them, each pair should be clamped together so that the holes coincide. Drill a small clearing hole before putting the correct size of drill through, this makes for a more accurate hole and relieves the task of drilling.

Ready-made FittingsAs I mentioned before, however, I can let readers have the name and address of manufacturers who will supply the various fittings; ready made.The total cost of £20, which I set as the limit, is on the high side, and will permit a certain amount of work being

placed out, although actually there is nothing which is beyond the skill of an amateur. I have arranged everything for simple construction without sacrificing strength or efficiency, and have had in mind, of course, the amateur as distinct from the professional.

Page E5                       May 1936                 NEWNES PRACTICAL MECHANICS              446     

The latter will, no doubt, adopt brazing, welding, and steel construction where I have used wood, although the latter is amply strong for the purpose, and has the advantage that it does not bend.

Low Centre of GravityWith the construction at this stage, do not make the mistake of starting the engine, since further

bracing of the chassis is necessary to secure rigidity. Notice that the forward end of the chassis is covered underneath to provide pedal room and to keep the centre of gravity low.

Give all of the wooden parts a coat of lead colour or dead black and do not forget to smear all bolts with oil.

Page E6                       May 1936                 NEWNES PRACTICAL MECHANICS              447   Place a little graphite grease in all of  the holes drilled in the wood. This will prevent rusting. The holes in the wooden part should be drilled of 1/64-in. larger diameter than the bolts and rods, otherwise the cling of the wood may tend to grip them and prevent them passing through.

Chassis MembersUse bits of the Forstner type, and drill the chassis members whilst they are clamped together to ensure all of the holes being in absolute alignment. It is a

good plan to mark out the chassis members on the floor with chalk, marking the position of all the holes which are clearly shown in the diagrams and photographs, and then to transfer these to the two main chassis members. This will make for easy assembly and quick erection.Use engineers' bolts with accurately cut threads ; these  may cost a little more, but they are well worth it.

Braking SystemI shall not deal with the braking or system of control, but shall devote

special drawings and descriptions of these in the next issue. It is sufficient to say that the normal type of accelerator pedal with the usual throttle stop is fitted, that the foot brake operates the rear wheel brake, and the hand brake operates the two front wheel brakes.  It is not necessary, contrary to what I stated in the first issue, that the brakes should be coupled. The gear lever consists of the lever and gate as fitted to the tank of a motorcycle and is mounted on the side of the chassis, as shown in one of the illustrations.

The L Plate.One or two readers have pointed out to me that as the official designation of a three-wheeler is that it is a motorcycle, it is unnecessary for a beginner to be accompanied by a skilled driver when the former is learning to drive, although he must, of course, fit the "L " plate if he did not hold a motor-cycle driving licence prior to April 1934. This is so, and 1 gladly draw attention to it.Several other readers wonder how they are to apply for registration. This must be done through the offices of the nearest County Council, and it must be registered as a car of your own make under the heading " Make of Car." You must give all details of the colour, where the, car is garaged, and so on. Numbers will then be assigned to you which must be painted on according to the official regulations.I shall give a drawing next month showing how to lay out the number plates.

The Driving LicenceIf you are not old enough to, apply for a licence to drive any motor vehicle, apply for a licence to drive a motor- cycle, providing you are of  the age which entitles you to that. This will legally entitle you to drive a motorcycle or a three-wheeler. It must be remembered that it will be necessary under the Road Traffic Act to take out a third party insurance policy, which may be effected through any insurance company.

Page F1Final Constructional Details. Previous Articles on this Fascinating and Easily Built Three-Wheeler Appeared in our Issues dated March, April, and May. Blueprints are now Available. The Designer, Mr. F. J. Camm, grants a Free licence to Every Reader to Build One

I SHOW this month photographs and drawings which will enable the reader to complete this fascinating little

vehicle, of which many hundreds are being built from details in this journal. Before dealing with them I should like to dispose of a further batch of queries. Firstly, regarding insurance. Several readers have asked whether there will be any difficulty about this. I have accordingly been in touch with several insurance companies, none of whom have any objection to insuring the car. Messrs. Premier Motor Policies tell me that they are prepared to issue a third-party insurance policy for £3 7s. 6d., and I recommend readers to get into touch with them.

RegistrationAn important point occurs regarding registration. In the item on Form RFI, which must be filled in in order to obtain the necessary registration numbers, there is a line reading "maker's name." I have been in touch with the London County Council on this point, and would inform readers they must enter the make, as " Camm." The registration figures assigned to my own car are CXR547, and if any reader should spot me on the road do not hesitate to stop me if you wish to ask any questions and inspect my vehicle. I expect in the near future, as time permits,to embark upon a series of timed runs, of which I shall disclose details in due course.Many readers are asking where they can get fittings made, and 1 have accordingly arranged with several manufacturers for this to be done at nominal prices. I can let you have these addresses upon application if you will enclose a stamped and addressed envelope. You will appreciate, of course, that the price of the finished car may come out a little higher than £20, if you elect to have some of the parts made, although £20 is actually on the high side.

Number PlatesRegarding number plates, Messrs. Bluemel Bros., Ltd., of Wolston, Coventry, will supply special plates for this car. You require one model K and one model A plate. In, writing to them you must, of course, state the registration numbers assigned to your car.

Page F2                       June 1936                 NEWNES PRACTICAL MECHANICS              499

The plates will then arrive with very neat and serviceable celluloid figures already attached so that the number plates may be immediately affixed to the car, thus avoiding the troublesome business of painting the numbers yourself to the legal dimensions.

Cushions etc.Some of my readers do not seem too keen on making  a cushion, a back squab, and a hood. Here, Messrs. Austers,

Ltd., Crown Works, Barford Street, Birmingham, come to the rescue, for they have made at my special request a back squab, a cushion, and a hood. They will supply a very neat windscreen, which also has been specially designed for the car. I recommend readers to use those parts.  The colour of the upholstery, which should be chosen to tone with the paintwork of  the car, should be stated when ordering. My own car is painted with cream cellulose applied by means of one of the cheap Spray-on guns supplied by the County Chemical Co., Ltd., Chemical Works, Bradford Street, Birmingham, who also supply the spraying cellulose.

ColouringThe mouldings and the wings are in maroon, whilst the imitation louvres on the bonnet are picked out in black. You will, of of  course, choose your own colour scheme.No provision is made for a dynamo on this car, since there is very little need for one. The car starts quite easily, and it is a simple matter to have a spare accumulator on charge. I  have been in touch with Chloride Company, who are arranging to supply a special 6-volt battery for this car. When ordering ask for Exide 3.CZN7- IL. This battery is of 30 ampere-hours' capacity at the 20-hour rate or 27 ampere-hours' capacity at the 10-hour rate; and is therefore quite ample to feed the two wing lights, the rear light, and the horn.

6-volt LampsYou must use lamps of the 6-volt double-pole type, and a convenient and quick way of coupling them up to the battery is to take two leads to two strips of brass fixed behind the dash. These two strips of brass will form common bus bars from which the leads to the horn (fixed in the centre of the radiator), and  the lamp may be taken. This will save a multiplicity of leads to the battery. Excellent, wing lights, rear lights, and horns are obtainable from James Grose, Ltd., 379 Euston Road, N.W. I.  They are cheap and efficient. This firm will also supply the car type of mudguards if you decide to use those instead of wooden ones. My drawings have shown both types.

PageF3              June 1936                    NEWNES PRACTICAL MECHANICS                        500

A  point 1 wish to stress is that I grant every reader of this paper a licence free of all charge to make one car. In no circumstances must it be made for sale, since it is likely that this car will shortly be placed on the market.The mudguards I recommend if you use the metal type are the model 109 from Messrs. Grose's catalogue. May I also repeat that my drawings are correct for the components I have already specified, but you will need to modify them if you are using other parts.

Remedying WhipOne or two readers tell me that they have found the members whip slightly near the front. This is due to the use of unseasoned wood, but it is not a defect which need worry them. Fortunately they will be able to get over it very easily by incorporating the cross-bracing between the axle and a point beneath the floor. My own car has not the slightest trace of whip.I  show in the sketches how to make the adapter for coupling the magneto to the drive shaft to the engine. This detail, of course: applies to the Burney and Blackburne engine and the B.T.H. magneto. If you have bought  an engine with magneto attached you will ignore it. I also show drawings for the extension shaft of the kick-starter and the means of attaching it to the gearbox. A guide plate is  fixed outside the body which has slots at the top. Coach screws secure this  plate to the side members, and it will be necessary to slacken them off when  adjusting the front chain tension, since the the guide plate must move back with shaft of the gearbox.

Exhaust Pipe and SilencerIf the engine has not an exhaust pipe and silencer attached, you should use flexible metallic tubing, which is secured to an adapter locked to the exhaust stub by means of the union nut secured to it. A sketch shows the general method employed in framing up the superstructure. It will be seen that angle plates are used.

PageF4             June 1936                    NEWNES PRACTICAL MECHANICS                        501

These are known as upholsterer's plates and may be purchased from any ironmonger. In fixing the dash the curve should be cut carefully so that sufficient leg-room is left. This will vary with the individual. Notice that the stop collar at top of steering column is pinned to the latter, and that the lug acting as a guide and anchor for the column is secured to the dash by means of three bolts.

The PanellingThe photographs themselves are almost self -explanatory, and have been taken at various stages of construction. I do not think that any special difficulty will arise. The panelling is attached to the uprights and rails by means of panel pins, and the joints are obscured by half -round moulding. Note that the edges of the seat compartment are upholstered with a rolled edge. The door will need to be covered with three-ply and finally with a piece of the same material as the cushion and squab. A similar panel should be cut for the offside of the seat, compartment. A good method is to cut the panels, cover them with American cloth, and then to fix them.

PageF5             June 1936                    NEWNES PRACTICAL MECHANICS                        502Guide for gear rod.

Making a Hand BrakeIf you are unable to purchase a hand brake you may easily make one as shown in the sketches. Bowden cables are used for the foot brake, the accelerator, and clutch. The gear change, of course, must be a rod, and a guide plate should be attached to the side member as shown in one of the sketches. The. rear suspension springs may conveniently consist of very strong motor-cycle front-fork springs, although Messrs. Herbert Terry & Sons, of Redditch, are supplying special springs for the job. If you are able to pick up a. pair of springs and find them too short for the job you may make use of them as shown in one of the diagrams by fastening a piece of angle-iron to the rear cross-member and anchoring them by means of an eyed extension bolt.Blueprints for the car are now ready but are limited in number. They cost 10a. 6d. per set of foursheets, and show the general and detailed arrangement of the parts..It will be noticed that regarding some of the details the reader win be left to his own devices, since I cannot issue

drawings applicable to all of the engines,gearboxes, and other parts which are being used by constors of this car. The general arrangement must, however, be followed; theshapes will remain and details will differ only as to dimensions. In no case should a twin-cylinder engine be used. since these are of greater cubic capacity and will impose strains and stresses for which the ear is not designed.

Cellulose SprayingI have mentioned that readers will decide upon their own. There are,  however, the general methods to be employed. I recommend cellulose spraying since no amateur can hope to get a professional finish in any other way. There are several excellent brands of brushing enamel on the market, it is my experience that amateurs will never go to the trouble of preparing  the work ; most of them presume that a coat of paint will hide a rough surface; it will not. It is always wise to rub down the the woodwork, to fill up any depressions, sscratches or defects with a suitable woodfiller such as plastic wood, to give a co priming (which must be of a lighter colour than the final coat), and then to finish either by brushing on enamel or spraying on cellulose. Remember that, as purchased the latter is intended to to he applied by means of a brush and a reasonably satifactory   job can be made in this way. You can obtain for 1s  or so a spray-on gun, by means of which you can obtain quite a professional finish, although the cellulose will need to be thinned with cellulose thinners uaing 50 per cent. of each. These guns have a container at one end in which the thinned cellulose is placed. A pump arrangement   similar

Page F6 June 1936 NEWNES PRACTICAL MECHANICS 503to a cycle pump causes a jet of air to pass a jet of air into the container, and thus the paint is induced from the jet in the form of a finely atomised spray In this form it settles on to the woodwork very evenly, and apart from this the method uses very little paint. All joints in the mouldings should be filled with plastic wood, of course, first. After the first coat rub down with pumice dust applied to a piece of wet felt and give a second coat, finally finishing with a soft cloth on which is applied a small quantity of one of the well-known cellulose polishes. If you are using a two-colour scheme for the body it

will be necessary to mask off one portion when applying the second colour. This may be done by cutting brown paper masks to fit the parts not to be coloured, and directing the paint spray away from the edge of the paper. If you reverse this process the paint will creep under the edge and give an irregular and crude effect.

The RadiatorThis can be made to simulate a genuine one by fixing a form of netting known as expanded metal. This will need a framework made and mitred together from rebated material such as plain picture framing. The expanded metal will fit inside this framework. it should be painted in aluminium colour for effect. Any simply made piece of carved wood will serve as a dummy radiator cap.The whole of the radiator assembly should be fixed by means of screws so that it can easily be removed for adjustment to the pedals. This also applies to the tapered-off rear section, so that it will be an easy matter to remove the rear wheel without jacking up.

References: