Articulating deck helps mower follow contours of new landscaping trends.

In response to the contoured landscaping trend employed by golf courses, commercial and residential properties, Indianapolis, Ind.-based LasTec has introduced two new diesel-powered zero-turn radius (ZTR) mowers with articulating mower decks. The 325D Articulator and 425D Articulator mowers feature

LasTec created its Articulator concept in 1990. Dan Tekulve, owner and operator of a local golf course, had problems mowing the earthen mounds designed into his course without scalping or scuffing the turf. According to Jeff Laskowski, COO of LasTec, the options were to use a labor intensive approach - cutting the mounds with push mowers - or continue to scalp them with other equipment. Instead, Tekulve and Laskowski founded LacTec, and developed the Articulator mower design, the first incarnation of which was a towable, PTO-driven design.

"Nobody plants flat grass anymore," said Laskowski. "The growing trend in landscaping is to add contours to the ground. On golf courses this is evident with bunkers and mounds around tees and greens and in the fairways. In commercial and residential areas mounding is incorporated for aesthetics or as sound berms.

"With this mounding trend, grounds maintenance crews are looking for ways to effectively manage an area without hiring armies of people with small equipment."

The 325D and 425D Articulator models are each powered by the Kubota 1505-B1 liquid-cooled, four-cylinder diesel engine rated 38 hp. The engine packages are sourced from Capital Engine, Reynoldsburg, Ohio, and incorporate Tech Products isolation mounts and Donaldson air cleaners and Turbo Two precleaners from Turbo Industries. Racor fuel filter/water separators and oil filters are also supplied with the engine packages.

Capital Engine also supplies an oversized radiator. "The standard radiator package did not provide adequate cooling capacity in extreme mowing conditions," said Laskowski. "With the oversized radiator we effectively doubled the cooling capacity of the system."

Ground drive and differential steering for the 325D and 425D Articulator mowers is hydrostatic and actuated mechanically by two hand levers mounted next to the operator's seat. The engine drives, via two Goodyear belts, twin Hydro-Gear BDP21L variable displacement piston pumps, each displacing 21 cc/rev. Each pump powers a Parker Hannifin MB29 wheel motor. The wheel motors have a displacement of 29 cu.in./rev and each drives Titan wheels and tires. The motors have internal pressure relief valves set at 2500 psi to regulate system pressure.

The hydraulic system routes oil from the two low-pressure bypass circuits through a single Long Manufacturing oil cooler, which is mounted ahead of the engine radiator for higher cooling efficiency. During initial product development Laskowski noted that components on one circuit ran hotter than the other. According to Laskowski, cooling the hydraulic oil from both circuits in a common cooler allows the oil's temperature to stabilize and equalize across both sides of the system. This keeps the temperatures well within the component specifications, even in the most severe conditions.

Hydraulic oil is filtered by a 40 micron cartridge type spin-on filter element. Hydraulic system plumbing consists of Dana Weatherhead and Parker Hannifin hoses and fittings.

"One of the most challenging aspects of designing these mowers was packaging all of the components as tight and low to the ground as possible," said Laskowski. "The mowers need a low center of gravity and a wide track to allow stable safe operation on extreme terrain."

The articulating mower deck is raised and lowered by a hydraulic cylinder operated by a foot-controlled mechanical valve from Hydroima. Power for this and other auxiliary hydraulic functions comes from an auxiliary charge pump mounted on one of the Hydro-Gear piston pumps. With this arrangement, Laskowski said the auxiliary system is capable of developing 800 psi of pressure.

The parking brake is a Hayes Industrial Brake mechanical disc unit, mounted integral to the wheel hub. Actuation of the brake is via a foot pedal.

The mower blade drive system is a combination belt/shaft/belt arrangement that uses a Dana Warner Electric Clutch mounted to the engine's crankshaft to engage and disengage the cutting blades. A double-groove, B-section pulley mounted to the clutch transfers power through a belt to a right angle gearbox from Curtis Manufacturing. The gearbox transfers the power from a horizontal to a vertical plane, with the output shaft, located on the backside of the gearbox, transferring power to the mower deck.

The patented belt drive system maintains constant belt tension and is in the 95 percent efficiency range in transferring the horsepower from the engine to the blades, according to Laskowski.

The 325D mower features three articulating, 25 in. wide rotary decks that flex independently for a 72 in. capacity with an 8 in. trim side overhang. The 425D mower features four articulating, 25 in. wide rotary decks for a 96 in. capacity and a 30 in. trim side overhang. Both mowers include ROPS protection. The operators station includes a Milsco Manufacturing seat and control panel with warning lights and audible alarms for critical parameters such as engine coolant temperature, oil pressure, and hydraulic oil temperature. An ENM Quartz hourmeter is also included.

For more information on the Articulator mowers, contact: LasTec, 8180 West 10th St., Indianapolis, IN 46214. Telephone (317) 273-1122.