YOUNGER BROTHER Mini-tractor must admit, I’ve built without any drawings (except the sketches of parts that he had ordered Turner), so to speak, to the eye, intuitive, having all components and assemblies as compact as possible and easier for the tractor. Then, the accumulation of operating experience, many times altered it. But more on that below. Built because I needed a mechanical servant, able to perform almost all the agricultural work on the plot. Such “abilities”, in my opinion, has tractor T-25 vladimirets. He was the inspiration when building my mini. Hence the nickname — “little brother.”

The similarity is only external, because I collected a mini-tractor of all that was at hand. Collected contrary to the canons. Started not from the frame, as is done usually, and that I have the engine UD-2 is equipped with a flywheel and clutch from the car GAZ-21. The flywheel attached to the crankshaft of the engine via an adapter that is manufactured according to the recommendations published in early issues of the journal “modelist-Konstruktor”, from blanks that are cut from the rear end “volgovskoe” of the crankshaft. This design subsequently proves to be excellent — for three summer work season did not need even the nuts to tighten!
The clutch housing was installed upside down — pan up, otherwise because of a rush for the speed controller of the motor starter are not docked. I even had a file to expand to 2 mm up holes vosko mounting box, as the flange of the bearing shaft was not aligned with the hole for the flange in the flywheel housing.
Then began the layout of the transmission. It is a chain or a bunch of different transmissions. And here I would like to elaborate on how many times and how I had the transmission redone. Let me explain: the following description is not a guide to action. In the end, each Amateur designer comes from their capabilities. We hope that the information will be appreciated by those who want the benefit of my experience and not to waste neither time nor money.
Wheeled tractor
Wheel tractor.
Adaptor and its position relative to the engine UD-2
The adapter and its position relative to the engine UD-2:
1 — end of the engine crankshaft, rear; 2 — adapter (from ending “volgovskoe” crankshaft).
Frame mini-tractor

Frame mini-tractor:
1, 3 — lower and upper side members (steel tube 60x40x5, 2 PCs); 2, 4 — strut front and rear (steel tube 60x40x5, 2); 5 — cradle the rear axle (2 PCs.); 6,11 — prop power plant, front; 7, 13 — prop power plant, the rear; 8 — bracket hydraulic distributor; 9 — the crossbar mounting counterweights (steel pipe 50×3); 10 — beam mount hood (steel tube 60x40x5); 12 — support of front axle (steel sheet s 12); 14 -an arm of fastening of a hydraulic cylinder; 15. 17 — cross member top and bottom (steel pipe 40x40x3); 16 — strut top (steel pipe 40x40x3, 2); 18 — Klondike bracket (steel sheet s5. 2); 19 — front bracket (steel tube 60x40x5, cropped).
Scheme of joint transmission

The scheme of the joint transmission:
1—CAT-1; 2 — shaft splined (UAZ-451); 3 — plate transmission-1, full-time; 4 — plate transition; 5 — bolt plates to CAT-1 (4 PCs); 6 — bushing remote (4 PCs); 7 —ring remote; 8 — stud attachment entrance gate No. 2 to the transfer plate (4 PCs); 9 — spline flange (UAZ-451), welded to the input shaft from the gearbox-2; 10 — CAT-2 (GAZ-51).

In the original version of the transmission after the engine was built the clutch basket and the gear box (transmission) from the car UAZ-469 (complete with junction box, which had its own reduction gearing) and slightly modified planetary gear from the two-wheel tractor MTZ-50. The last attached directly to the rear axle (instead of a flange, the retaining shank reducer of the bridge in its nest).
Rear axle mini-tractor — car UAZ-469. To reduce the gauge of the wheels, I’ve shortened it up to 1150 mm. Made it so the bridge was dismantled and Carter were taken to nearby repair shop. There on the big machine drilled spot welds and vibrissal crankcase housings of the axles. Cut them on a lathe to the desired size, grind the seats, pressed back, and welded by electric welding.
Unfortunately, such coupling mechanisms is not justified — in planetary reducer often had to add oil because it flowed into the axle housing and thence (through the housings of axles) fits in the brake drums of the rear wheels and broke them work.
So after the first summer season I refused to step-down planetary gear, though these bundles were a great set of gear: the lowest of them speed mini-tractors were from 3 to 5 km/h, which is very suitable for heavy work, in particular, to plowing of virgin lands and mowing of grass trailer mounted mower. Also made the junction box below, not extending base mini-tractor, put the transaxle from the car GAZ-69.
After the second summer season, it turned out that a new version of the powertrain leaves much to be desired. In the lower gears the speed of the tractor is significantly increased, which led to a deterioration of traction characteristics. Began to fail gear first and reverse gear.
Note to the doubters that low-power engine (8 — 12 HP) can “break” the axle shaft of the axle, automotive gear box or planetary gearbox. Can! Overall gear ratio in conjunction PPC is so great that develops torque as that of the tractor.
Following my mini transmission received from GAZ-51. It is 30 mm longer than its predecessor, so the rear axle was pushed to this distance, and its shank with the box connected movable gimbal mechanism of the two flanges and crosses.
But it in the end. And at first, graduating to compose the first version of the drivetrain, I posted it along with the engine, put on the axle of the wheel and started the frame. Traditionally, automobile and tractor frame design flat. However, all my attempts to follow the canons without success. Had to break down and solve a problem unconventional: the frame turned out spatially because different, I think, this powerplant to provide a “skeleton” was impossible.
The situation was further complicated by the fact that was not possible rationally to place the generator and oil pump. To mount them to the frame — it is impossible, but directly to UD-2 anywhere. So I used two spacers from steel channel 50×25 mm, pull-to-engine bolts M12. They were welded mounting brackets pump and generator. Place drive pulley V-belt drive them found on the front end of the crankshaft. There is a finned flywheel for cooling the engine. The flywheel I took off, bored through it landing on the neck, drilled four holes, tapped M8 and attached a pulley (water pump GAZ-21) with four bolts. The belt tension is regulated, for this purpose it is necessary to loosen the two bolts on the plate the tensioner and slide the plate down, tighten.
So, the power plant four control points; two front belonging to the motor, located on the lower frame rails, on rubber pads, and two rear belonging to the “wazowski” checkpoint on the upper longerons. Rear axle settled between the side members at a special lodgements.
In addition, to the frame welded on another set of beams, rails, struts, cross members and brackets, which are designed for different elements of a complex of the tractor body. For example, to the bar hanging from the counterweights, the beam supporting the engine hood, wide plate link front axle, uprights and crossbars bolted the cab to the brackets attached dvuhsotmetrovy dispenser’s hydraulic system and power cylinder.
By the way, the space frame provided rich opportunities to build within it the necessary mechanisms. I had no problems with, say, a search space for many more units of the hydraulic system. In the space between the upper and lower longerons, it would seem, filled to overflowing powertrain, rear axle, in addition to the already directional valve and a hydraulic cylinder freely is still a bulky water tank, hoses, controls, distributor, and hitch that I built into the frame later.
Hitch is suitable for towing removable agricultural implements (plough, harrow, discoveries, etc.) and a cargo trailer. It consists of two shafts rotating in bushings which are welded to the ends of the spars, as well as earrings, levers and power adjustable rods.
Later, in the process of operation it became clear that to work with mounted plow mini-tractor does not have enough mass. Had to weigh it down the front two balances from the “Vladimir” of 20 kg each. With them “the younger brother” went much softer, smoother and became more obedient to the helm.
Front axle, too, was given to me immediately. Where it was necessary to strengthen it, was the oil pump. Therefore, the attachment point had to shift back a little, and the axle beam to make a slightly curved — assigned forward ends so that the steering wheel remained in their intended place.
I-beam made of rectangular steel tube section 40x60mm allowances on the ends. Front for strength welded overlay (the same pipe), and the top — sleeve hitch. Then hung the beam to the second node of oscillation, which is screwed from below to a wide and thick steel plate on the lower frame rails. As the hub of the swing used a modified rotary axle of the car GAZ-53. The pivot — bolt of hardened steel, fixed in the sleeve hitch locking bolt. Bronze bearings are friction bearings.
Hanging the beam, I cut her limit allowances and grabbed the steering welding glasses with combined rotary axles-axle shafts. Grab them in Assembly with the wheel to see how it all will look. Two words about the axle-the axle shaft. Such a double name it is no accident, since it is machined in a single shaft, then heated in the flame of a gas burner and bent to an angle of 93°: one end of a shaft — rotatable axle, the other wheel axle shaft.
With the front axle is directly connected steering. Steering column I did this to the wheel it was possible to reject to itself or from itself, and even if you need to tilt forward for maintenance of the cabin and the entire tractor. To the front of the cab welded a tube — piece propeller shaft of the car GAZ-51. The very column was taken from the tractor MTZ-50. Removed all unnecessary, leaving only the tube and the shaft. The tube and the tube connected pivotally with parts of the propeller mechanism: cut the crosspieces of the landing of the neck, inserted in the bearings of a tube introduced between the pipe and tack welding; then carefully knocked out the bearings, took out the tube and the neck wound asbestos cord and welded them permanently. Turned out to be quite the rotatable structure fixed in the desired position the spring-loaded catch.
The column and the steering gear (it’s from the “Moskvich-412”) connected upgraded driveshaft (from an appropriate mechanism MTZ) that allows the column to deviate back and forth. Modernization was the fact that the shaft was trimmed, telescoping splined connection and customized locally.
And the track rods from the “Moskvich-412”, and also customized. Swivel arms combined, welded: one end of the lever (with your finger) — “moskvichki”, the other tractor.
From the “Moskvich-412” and the steering wheel. But as it is splined wheel hub did not fit to the pipe, I replaced it with the hub of the wheel MTZ-50.
I must say that the mini-tractor is very maneuverable. A turning radius of just 5 m. So that the roadway width of 6 m is enough for a turn in one go, not giving back and not stopping at the curb. And even farmland even in a few acres for him — still that field.
When the chassis was ready, I began to design the exterior of the mini-tractor. Mentally imagining how it will look cabin, and a veneer, I decided: something like “Vladimir”. And then the windshield, which I eventually found, I think that it is also from the tractor T-25.
The skeleton of the cabin, including rear and front rack and crossmember, collected from sections of steel pipe cross-section 40×40 mm, and the frame is made of lengths of pipe with cross-section 20×20 mm. the Front frame of the frame made the size of the windshield to fit the rubber edging. A hole in the frame below the edging made of sheet iron with a thickness of 1 mm, the joints treated sand around, clamped in the Chuck of the drill. The idea was to make glasses round. But as a mini-tractor operated mainly in warm years, decided not to complicate the design of the cab. For the same reason refused. And rain is enough to have a glass front so the roof over my head.
The roof I bent from sheet iron. Placing a thick Board snapped in the roof by marking the two edges of rigidity of a width of 100 mm and a depth of 3 mm blunted chisel. Did it gradually, day length over the time that the sheet is not led.
The layout of the power plant and drivetrain (some items frame conventionally not shown)
The layout of the power plant and drivetrain (some items frame conventionally not shown):
1 — the engine UD-2; 2 — spacer (channel, 2); 3 — clutch housing (UAZ-469); 4 — KHP-1 (UAZ-469); 5 — a plate-support CAT-1, full-time; 6 — transition plate (steel, sheet s 14); 7 — checkpoint-2 (GAZ-51); 8 — mechanism of the propeller; 9 — rear axle (UAZ-469); 10—the cradle of the axle; 11 —support of the power plant, rear; 12 — pole powerplant, the front (with rubber cushion).
Oil pump drive and generator
The oil pump drive and generator:
1 — engine; 2 — a pulley lead; 3 — strap wedge; 4 — M12 mounting the engine: 5 — spar of the bottom frame; 6 — engine mounting front; 7 — bracket fixing plate of the pump, right; 8 — bolt M10 mounting of the pump (2); 9 — plate-belt tensioner; 10 — a pulley of the pump: 11 — bracket of the generator; 12 — generator pulley; 13 — oil pump HIII-6 right rotation; 14 – bearing housing; 15 — bearings 204; 16 –key; 17 — shaft pulley splines; 18 spline pump shaft.

Mountable device:
1 — mounting bracket of the hydraulic cylinder; 2 — longeron upper; 3 — cylinder power; 4 — the lifting arm (2 PCs); 5 — earring attachment of the hitch of the plow; 6 — the lever of power; 7 — thrust side adjustable (2 pieces); 8 — cross member; 9 — spar frame lower; 10, 17 — upper and lower shafts (steel rod Ø 34); .11 — cheek restrictive (4 PCs); 12 — bushing-bearing (steel tube 40×2,5,2); 13 — spacer (steel tube 40×2,5); 14— .sleeve-bearing (steel tube 45×2, 2); 15 — ears of the traverse; 16 — pin (2 PCs); 18 — restrictive washer (2 PCs)
Front axle

Front axle:
1 — bushing hinge; 2 — a lining (steel tube 60x40x5); 3 — beam axle (steel tube 60x40x5); 4 — glass steering; 5 — thrust spring; 6 — the plug (rubber, oil resistant); 7 — axle-side shaft rotary; 8,11 — bearings 204; 9 — spacer; 10 — nipple (relatively rotated in the image plane); 12—bearing 958305.

1 — wheel; 2 — pipe (tube conventionally not shown); 3 — shaft; 4 — a splined telescopic connection; 5 — spar of the bottom frame; 6 — the steering mechanism; 7 — fry steering; 8 — thrust push adjustable; 9 — lever swivel steering; 10 — axle front; 11 —bearing axle; 12 — bolt M10 (6 PCs); 13 — thrust lateral; 14 — pin; 15 — node swing beams; 16 insert (bronze, 2 pieces); 17 — Bush linkage.
Steering column

Steering column:
1 — pipe; 2 — a spring-loaded latch; 3 — tube; 4 -5 — bearing cap; 6 — fork shaft.
The scheme of placement of controls, and auxiliary equipment in the cab and under the hood (roof, beam front axle and the steering column is not shown)

The layout of the controls and accessories in the cab and under the hood (roof, beam front axle and the steering column is not shown):
1 — ignition coil; 2 — fuel pump; 3 — cylinder of coupling; 4 — the relay-regulator; 5 — the main brake cylinders; 6 — control devices; 7 — lamp enable ground control; 8 — the ignition switch; 9 — horn button; 10 — throttle; 11 — brake pedal; 12 — a lock the starter; 13 — the switch of headlights and tail lights; 14 — levers of the hydraulic distributor; 15 —the lever of PPC-2; 16 — battery; 17 — fuel tank; 18 — the driver’s seat; 19 — switch battery (“weight”); 20 — tube cap hydraulic tank (on the floor); 21 — a coupling pedal; 22 — a gear box-1; 23 — tripping.

In the same way produced and the hood consisting of four panels. The top and sides of the hood, pry off they have a 10-mm edges inward, connected by electric welding. And the veneer is inserted into the pre-beaded in the other panels of the folds, and fastened with M4 screws.
The front fenders did the pattern. The flanks they were also minted. But unlike the roof and the hood, not in the stage of preparations, and ready-made products, when the wings were soldered.
Rear fenders and foot pegs welded blowtorch to the frame of the cab and to the top longeron. Before that, the pegs knocked out from the bottom of a blunt punch small holes to avoid slipping up.
The floor in the cabin made of 3 mm iron sheet. Cut in it holes for the filler neck of the hydraulic tank and controls. On the floor under the seat positioned the gas tank, battery and switch the “mass”.
The pedals in the cockpit hanging from the UAZ-452. With the help of a blowtorch for convenience, they are slightly curved upwards. The difference with a “UAZ” is that there are two brake pedals on right and left sides. The brakes are not locked, although simultaneously press one foot on both pedals.
On the dashboard in the cab-located fuel level, oil temperature in the engine and the pressure in the oil line, ammeter.
The ignition system is a mini-tractor “battery” like on the GAZ-51. Magneto, which had stood on the engine UD-2, I used as a dispenser by removing it from the ignition coil and inserting instead the little piece of rubber cut to the shape of the coil. Made it to high voltage wire from the car ignition coil you can wire it to the distributor cap. This ignition system makes starting the engine more reliable.
The fuel pump I used from the interior heater “Zaporozhets” (these pumps were installed on a wheelchair sidecars and cars Volyn). I must say that even without a dispenser it works perfectly! The fuel supplied to it through a fine filter (often called a sump) from the UAZ. The pump is integrated in the line between the filter sump and the carburetor. Runs from the electrical switch “mass”. After the float chamber of the carburetor fills with gasoline, the pump automatically stops.
The charging current generator monitors the relay-regulator PP-350. Front Parking lights I placed in the headlights near the lamp or low beam by drilling the holes for the reflectors cartridges light bulbs that are used for backlighting. Rear clearance lights located on the roof.
Painted mini-tractor in the following colors: trim, wheels, dashboard and roof in yellow, cab and wings — red, engine — aluminum powder in a nitrocellulose lacquer.
Finally a few words about what a mini-tractor can be aggregated. The main was a homemade single-axle trailer with a design capacity of 500 kg, although, as it turned out, it can withstand more. Body tipping trailer, equipped odnodolnym hydraulic cylinder from machinery. The height to which he raises his body just enough to stall bulk cargo. To unload the trailer and pushing the back or side walls.
In addition, there is mounted a homemade plow. His body taken from back of a plow horse. Ahead of the plow blade is mounted circular knife. The depth of furrow is regulated by a wheel or shingles. The plow digs a small harrow, which dragging of the blade, crushing the layers of the earth.
M. ANTONOV, s. loyno, Kirov oblast

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