The first snow trac article

One Trac Mind: Snow-Trac

How what started as a private runabout for its designer became a worldwide commercial success

It all started in Sweden around 1954 when Lars (Lasse) Larsson decided to build a tracked recreational vehicle to take him to his cabin in the remote village of Oviken in the west of Sweden and on winter fishing trips. Lasse worked as the chief design engineer for the Swedish agricultural equipment manufacturer, Westerasmaskiner AB in Morgongava. Larsson was a talented engineer who built, amongst many other things, his own motorcycle in 1927 and his own 3D photo camera.

Lasse wanted a vehicle no bigger than a family car that would be reliable in extreme weather conditions. Naturally then, he chose the VW air-cooled flat four to power it, in this case an industrial version (53bhp) of the 1600cc type 126A engine. It wasn’t just the engine that had a VW part number on it, the four speed synchromesh gearbox came out of a VW Bus. Unlike the Volkswagen design though, the engine and ’box were fitted into the front of the vehicle with a chain drive to the front drive sprockets. Other VW components included the steering wheel and parts of the lighting system.

” In total, around 2,350
vehicles were built “

Traditionally, most tracked vehicles are steered by levers, their operation slowing the drive to one track, either by a brake or clutch mechanism, as the other continues to turn at full speed. But Lasse wanted to drive the Snow-Trac like a car, so he incorporated the Westerasmaskiner ‘variator’ steering system, which had been developed by the company for use on combine harvesters. It used a steering box with a pulley on it and a v-belt, which directed the full tractive force to one or other track during turning, and to both equally when travelling straight ahead. Though the unusual steering system took some getting used to, it made the 12ft long, 6ft2in wide vehicle very nimble, with a turning circle of just 8ft3in.

Snow-TracThe tracks themselves were rubber with rayon fibre reinforcing, and were made up of three separate, continuous bands, held together with approximately 75 u-shaped steel ‘track grippers’ riveted widthways onto the outside edges. The tracks were spaced to have two open grooves along their full length, into which the double drive sprocket teeth protruded and connected with the grippers for traction. On the inside, also riveted to the track, were numerous v-shaped supports and four undercarriage wheels ran between these supports so the track ran in line. These small wheels had 4.00 x 6 pneumatic tyres fitted. The undercarriage assemblies were sprung using two inverted leaf springs on each side, dampened by shock absorbers. Above these was an assembly with a centre track support wheel fitted, while behind the drive sprocket was a large front guide wheel supported by a short stub axle. This was repeated at the rear of the vehicle with both wheels having solid tyres. The hydraulic braking system comprised drums on the inside of the drive sprockets with VW brake shoes, operated via a foot pedal, and a handbrake for parking.

The bodywork was constructed around a steel frame with a large ventilation / escape hatch in the steel roof, with entry and exit gained through the single rear door. All of the other exterior panels were constructed from aluminium.

Commercial proposition

Lasse’s concept proved sound, and what initially started as an idea for a personal recreational vehicle became a commercial proposition when, after three years of use and development, Westerasmaskiner AB bought the rights and put the Snow-Trac into production. The first official model was the ST4, which soon caught the eye of the Scandinavian armed services, as well as organisers of Arctic / Antarctic expeditions and ski resort operators. As a result, there followed the ST4B, or Trac-Master, (later nicknamed the ‘Weasel’) with much wider tracks and a hydraulic pump fitted to operate front and rear-mounted snow grooming rollers. When it became clear the vehicles were as at home on sand as they were on snow, there was wider military interest, including from the British Royal Marines and REME, which led to a further range of military variants being produced with different body styles.

In 1969, another Swedish agricultural equipment manufacturer, Aktiv & Fischer, in Stockholm acquired the rights to the Snow-Trac from Westerasmaskiner and continued building and selling them worldwide until production ceased in 1981. In total, around 2,350 vehicles were built.

British platesSnow-Trac

It won’t have escaped your notice that the two orange Snow-Tracs in the feature are on British number plates. Here’s where I come in. From 1978, I worked as a vehicle fitter for the North Eastern Electricity Board (NEEB) and, in 1972, the transport department of the board purchased a Snow-Trac at a cost of around £2,000. This in itself was unusual because, up until then, the board had a policy of only buying British manufactured vehicles. That first ST4, registration number CPT 606L, was operated from the depot at Penshaw, Co. Durham.

The board had a strict health and safety approach to all equipment they purchased and Transport Manager, Ray Eland, had to give assurances to the safety department that no driver of the new vehicle would be put at risk whilst carrying out his daily duties. The Snow-Trac was bought to be used in remote rural areas to maintain the overhead line network (OHL). For safety, it had to be fitted with a rollcage, which was also strong enough to carry various OHL gear and a linesman’s ladder. After much deliberation, it was decided to use aluminium scaffolding poles for the structure, with the frame ‘legs’ bolted to each side just below the side windows and the front ‘legs’ fixed just in front of the track covers / wings. The joinery department made two wooden storage boxes that were mounted to the ’cage for smaller tools and service parts.

Word soon got around about the vehicle and other OHL departments wanted their own. By this time, a dealership – Alexander MacLarty of Crieff, Perthshire – had been set up to assemble Snow-Tracs, which made it straightforward to buy vehicles and spares.

The last Snow-Trac was bought by the electricity board in 1987, six years after Aktiv & Fischer had officially ceased production, again commissioned for use by the OHL department. That final one, registration number E526 ETN, was bought to replace an older ST4 that had been operated from the NEEB depot at Hexham, Northumberland.

The same, but cheaper

I was given the job of preparing the vehicle for its working life. Ray Eland told me of the work done to CPT 606L and said he wanted the same carried out on the new vehicle, though, “On no account were aluminium scaffold poles to be used because they worked out so expensive.” As I was a good welder, I was allowed to make the new ’cage out of steel instead. I used 3in square tube for the frame, with lengths of 3in angle for the front part of the ladder racks. The board used MOD-spec all-weather canvas straps with brass buckles on the boxes. When complete, a couple of coats of black Hammerite paint were applied, and then the frame was lifted onto the vehicle and bolted into place. Instead of the wooden boxes, I added some flat wood to the top of the track covers for storage. Other work carried out was the fitting of two directional searchlights, a warning beacon, a Pye Westminster two-way radio and it was finished off with fleet numbers and company logos. There was an addition bonus with this vehicle, in that it came fitted with an Eberspächer petrol heater, whereas older Snow-Tracs relied on the standard Beetle heating system.

E526 ETN gave good service with the company until it was auctioned off in 1997, though as the Hexham area didn’t experience particularly high levels of snowfall, it spent much of its time parked in the depot yard on its trailer (all electricity board Snow-Tracs had their own dedicated trailers). But when the white stuff did come, the Snow-Trac was ready to go.

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