A modern day lawn mower

Many of the members will have seen the machines we use out on the course, all designed to be used on a specific area. Depending on the length of grass and type of finish we require determines which machine and units to use.

Today we have been servicing the john Deere greens mowers so I thought it would be an ideal opportunity to share what makes them different from the rest to cut the greens. 

Firstly the greens are cut anywhere from 3 mm to 5 mm, this in itself warrants some specific requirements, the units have to be able to cut low without damaging the turf, be able to cut frequently to produce a good finish and the machine has to be able to travel on the green without causing any damage. 

Firstly the cylinders have 11 blades which can produce a high frequency of cut (0.71mm/kmh). This ensures a smooth finish, critical for a greens surface. 

Secondly the blade (bottom blade) is very  thin to ensure the height of cut can be as low as it is. 

This is a brand new bottom blade and is only 2 - 3 mm thick on the leading edge. Tournament blades are thinner than this to cut as low as 2mm however will not last as long. 

The critical point when servicing the units on any mower is to ensure the angles are correct. By this I'm referring to the relief angles on cylinder blades and top and front of the bottom blade. For this particular machine we put a 5 degree angle on the cylinder, 6.5 degree top and 15 degree front. This creates the scissor action that cuts the sward and remains sharp throughout there life. 

The front roller is grooved to ensure the grass isn't flattened before cutting. The back smooth to create the finishing roll. 

All the unit is striped down when serviced and cleaned then reassembled checking wear, breakages and greasing where needed. 

The final piece of technology which is required to produce fine turf are groomers. These are thin vertical pieces of metal spaced around 10mm apart. 

They are not used every time we cut greens but can be lowered when needed. They are used to remove lateral growth that is usually associated with bent grasses. These differ from scarifying units, as these don't penetrate the soil surface, where as scarifying can go into the soil and thatch around 3 - 4mm. 

When all assembled look a little like this. 

Unit before servicing. 

After each day of cutting they are always checked for blade contact and greased up after around 50 hours of use. 

The machine itself runs on smooth tyres which has a low pound per sq inch footprint, this ensures very little impact on the greens surface. It is powered by a 20hp 0.7 litre 3 cylinder Diesel engine, with the whole machine weighing only 700kg including operator. 

So next time you see us out on our 'lawn mowers' hopefully the technology we use  to keep the grass cut will be a little clearer.