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Midget Sports Car Fair warning! Don't let your kids see this story!or you'll find yourself in the midget car business. By Paul Wagner M AYBE we should have titled this story How To Flabber- gast The Short Pants Set—be- cause the youngster who finds this snappy, pint-sized roadster beside- his Christmas tree or birthday cake will be certain you are a me- chanical magician disguised as an ordinary mortal. Actually, you don't have to be a CONTINENTAL, single-cylinder two. hp lawn-mower engine powers the cor. Mechanix Illustrated

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Midget Sports CarFair warning! Don't let your kids see this story!—

or you'll find yourself in the midget car business.

By Paul Wagner

MAYBE we should have titledthis story How To Flabber-

gast The Short Pants Set—be-cause the youngster who finds thissnappy, pint-sized roadster beside-his Christmas tree or birthdaycake will be certain you are a me-chanical magician disguised as anordinary mortal.

Actually, you don't have to be a

CONTINENTAL, single-cylinder two.hp lawn-mower engine powers the cor.

Mechanix Il lustrated

ELECTRIC-WELD construction of angle-ironframe sustains vibration caused by engine.

COMPLETED FRAME and preformed Fiber-glas body are now ready to be assembled.

magician, mechanical or otherwise, tobuild this elf s delight of a sports car.So, if you'd like to really thrill yourmoppet with a plaything he'll rememberthe rest of his life, then continue on tothe construction details.

Chassis. The chassis of our littlesports car is of l-1/4xl-1/2-in angle ironexcept for the front extensions and therear cross-member. For these, we

used lxl-inch angle because the widermaterial was unnecessary and the ad-ditional clearance provided by the nar-rower material was desirable. All theheavier angle was used with the widerside facing up to provide maximumwidth mounting surfaces for the car'scomponents.

As a first step, cut all angle-iron sec-tions to size and lay them out for as-

118

sembly. The sections are then weldedtogether with overlapping joints at thecorners. Square-cut the corners andoverlap the joints for ease of fabrica-tion and for greater strength. You maynot have the facilities for doing yourown welding so it is suggested that youfirst assemble the entire chassis, usingscrews or bolts to hold the sections to-gether, and then have it electricallywelded by a professional. It is essentialthat the chassis be assembled withwelded joints because of the normal vi-bration created by the car's single-cylinder gasoline engine.

The body is mounted to the chassisonly at the ends. Its sides are supportedby the floor board which rests on thechassis rails and which is sufficientlythick to provide additional support tothe angle-iron framework. The bodybolts to the under side of the floor boardleaving the interior of the car free ofprojections such as brackets, angles, etc.

Body. The car's 67-inch prefabri-cated body was purchased from theAmroc Engineering Company of IslandPark, N. Y., for a little under $60. Youcan take your choice of one of two types;both are the same in appearance, con-struction and weight (22 lbs.) exceptthat one has a removable deck lidwhereas the other is solid. The solidbody is usually used where electric orpedal power drives the car. However,when a gasoline power plant is usedease of accessibility is an important fac-tor in starting and servicing the engine,so the body featuring the removabledeck is preferred.

All Amroc bodies are supplied with-out the rear wheel cutout. This per-mits the individual builder to decide onwhat type of wheel opening he wouldlike. We decided to use the full-circlecutout in order to give the car a morebalanced appearance. This was easilyaccomplished using a saber saw.

The car's headlights utilize lensesfrom a pair of 1955 Buick back-up lightstogether with flashlight bulbs and re-flectors. The tail lights are red auto-mobile clearance lights. The horn isthe same type used on bicycles.

The Amroc steering wheel is of castaluminum, the windshield of Plexiglas,and the upholstery of whatever materialyou choose. Finishing the body re-

ASSEMBLY DETAILS can be seen in thisshot of front axle and steering mechanism.

FRONT SPINDLES, turned from 5/8-inchstock, are same diameter as wheel bearings.

SMALL SPROCKET and steel pulley onthe countershaft must be welded together.

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LIGHT SANDING of molded body roughensit sufficiently to allow paint to adhere.

REAR WHEEL CUTOUT design is up toyou; bodies are built without this cutout

quires only a light sanding to roughenits smoothly molded surface so that thepaint will adhere. After sanding, sprayon a coat of automotive primer, thenfollow up with a finish coat of lacqueror enamel.

Suspension. The car's suspension issolid in the rear and semi-sprung in thefront. Actually, in a small car of thistype which is not subjected to highspeed cornering, a solid suspension allaround would be satisfactory. Wesuspended the front only to insure that

all four wheels would distribute thecar's weight equally. Cars of solidsuspension often have a tendency toweigh heavily on three of the wheelswhile the fourth wheel barely touchesthe ground. This problem is eliminatedby the use of a pivoting-type frontend. The actual weight-supportingpoints then become the two rear wheelsand the center of the front axle. Thetwo springs under the front axle merelyprovide a leveling tension that keepsthe axle from [Continued on page 156]

TO PAINT, spray on automotive primer,then follow up with enamel finish coat.

REMOVABLE deck lid makes engine acces-sible for both starting and repair chores.

Midget Sports Car

dropping too far away from the framewhen the car is lifted off the ground.

The car's axles are made from squaresteel tubing that provides a flat surfaceon which the springs ride.

The front spindles are machined fromstock of the same diameter as the wheelbearings. Wheel bearings, 5/8 inches I.D.,were used on this model, so the spindleswere turned from 5/8-inch stock.

The kingpins are standard three-inch,half-inch-diameter shoulder bolts. The tierod and drag links ends are of heavy-dutycarburetor linkage ball joints. The steer-ing knuckles are bent up from flat stock,and the spindles welded on as shown inthe diagram.

Drive system. A single-cylinder, two-hp,Continental lawn-mower engine powersthe car and, with its gas tank relocated asshown, will fit in a minimum of space.While a new engine will cost between $40and $50, a good second-hand unit willserve just as well and can be bought formuch less.

The clutch used in this car is the V-Plex.This is a simple, foolproof type that is com-pletely automatic and gives trouble-freeservice.

Installing the countershaft is the nextstep. Our counter-shaft, designed to givean over-all reduction of approximately9.5:1 from engine to wheels, will be suffi-cient to drive the car at a top speed ofover 20 mph—fast enough for the five- toten-year-old who drives it. If desired,other ratios can be installed by simplyvarying the size of the large axle sprocket.

Although this car uses a roller chainfrom the countershaft to the axle, a V-beltwith pulleys will prove satisfactory wheresevere usage is not anticipated. The smallsprocket and steel pulley on the counter-shaft must be welded together, but don'tapply the weld near the oilite bushings asthis will cause them to lose their impregna-tion of oil.

The drive chain runs from the smallcountershaft sprocket to the large axlesprocket. This latter sprocket, whenproperly tightened on the axle, requiresno key; it is held on the shaft by compres-sion. The chain is adjusted by moving thecountershaft fore and aft in the slotted

[Continued from page 121]chassis holes; the belt is adjusted by mov-ing the engine on its slotted holes. Theaxle is supported on the chassis by twoself-aligning ball-bearing pillow blockswhich prevent binding of the axle whenthe chassis is in motion. The pillowblocks, mounted on spacers of one-inchoak, serve to elevate the rear axle andkeep the chassis in a level position.

The axle is machined from one-inchstock to insure rigidity. One end has amilled keyway for the drive wheel; theother end is turned to the diameter of thewheels' ball bearings. The one-wheel driveeliminates the need for a differential.

The brake is attached directly to theaxle and acts upon the drive wheel. Itutilizes a V-belt and pulley arrangementthat is both simple and effective. The ac-tuating lever is mounted to the floor ofthe car and looks like a gear shift lever.

You should be able to complete this carin about six weeks of spare-time work. Weguarantee you'll consider your labors wellspent when you roll this baby off the "as-sembly line" and present it to your breath-less offspring—the luckiest kid in theblock. •

156 March, 1959