A lot of a caretaker's attention is focused on issues such as the maintenance of turf quality, fertilisers, mowing, topdressing and irrigation. One aspect of sports field presentation that is important to both players and spectators alike, is the way the pitch is marked out.
Field marking is an important component of the laws of all games. These lines define the boundaries of the playing arena and serve many other purposes to do with the conduct and control of the game.
For many years ground staff did not have much choice about how the lines were made. Lines were frequently burnt into position with oils, herbicides and corrosive powders such as lime. Nowadays more choice is available. Also with more attention being paid to health, safety and environmental issues, turf managers are looking closely at the long-term effects that the use of these chemicals has on the ground and on the sports men and women who use the grounds.
Many school caretakers are actually unaware of the legislation regarding herbicides etc. but even though there are now specialist line marking materials available, there are still cases where pitches are being marked with older options because 'that's the way its always been done' or because it saves time over the full season and cuts costs. But whatever reason, the end result is usually less satisfactory than if the correct materials were used. Lines marked with oil or glyphosate are likely to become much wider than required. With no turf to stabilise the surface the soil or sand in the vicinity of the line is likely to become hollowed out, leaving an uneven surface which could potentially cause serious injury to players and lead to actions brought against the club or pitch owners. The quality of the game played can also be compromised when ruts develop where lines should be.
For years the transfer wheel machines were the only option for wet marking and a basic gravity fed machine was the only option for dry marking. Over the years line marking has become far more sophisticated so that now there are many types of machine to choose from.
TRADITIONAL LINE MARKING METHODS - LIQUIDS
Transfer wheel (Wheel-to-wheel)
With this type of machine, fluid is transferred from a wheel rotating in a tank to a wheel marking the ground. This is suitable for grass surfaces Of the line marking innovations that have come and gone, the transfer wheel marker is probably the most enduring. Transfer wheel machines are still being sold today at very economical prices. There is also very little to go wrong with them with minimal moving parts.
A moving belt system provides a continuous supply of marking fluid onto the marking wheel. This is suitable for most surfaces.
The marking compound is stored in a reservoir fitted with a tap and mounted at an incline toward a single front wheel. The pitch marker liquid is fed by gravity through a filter to an absorbent marking roller. This is also suitable for most surfaces.
TRADITIONAL LINE MARKING METHODS - DRY POWDERS
Dry material is gravity fed from a plastic hopper. A shutter allows the line width to be adjusted. Modern machines have a bristled brush driven by the wheels for even distribution of the powder. Dry markers, like transfer wheel machines, have stood the test of time. With powder marking it is possible to get a build-up of the compound to create a highly visible and durable line.
Another traditional method involves mixing these fine white mineral powders such as limestone or dolomite with water to produce a liquid pitch marker for use with a transfer wheel machine. This process can be messy and time consuming and is unnecessary with the specialist alternatives around i.e. liquid marking fluids.
MODERN LINE MARKING METHODS
Spray - Pedestrian
Spray application of the pitch marker fluid is a more modern innovation. Battery powered or wheel-driven pumps force marking fluid through a nozzle and onto the surface. The width of the line can be varied with different jets and specific line forming attachments. Suitable for all surfaces and conditions.
Line markers can either be specialised machines, or attachments are available to convert small boom sprayers to line marking duties. (Likewise some specialist line marking machines can be converted to a sprayer with the addition of a small boom)
A machine that can mark out on both hard and grass surfaces has an integrated water tank for cleaning, powerful pump and rechargeable battery is an excellent investment for the discerning caretaker.
Spray - Ride-on
The advance of technology is apparent in all industries and the line marking industry is no exception. For the large user there are high tech ride-on line-markers available. This type of technology is a far cry from the days of burning the lines in with oil applied from a transfer wheel marker. Top-of-the-line ride-on machines are capable of marking at speeds of up to 30 kmph, and marking around goal posts whilst staying on the same drive line. An average soccer pitch takes approximately 20 minutes to mark out with a traditional pedestrian marker. However, with a ride-on line-marker this time could be reduced to as little as 7 minutes per pitch! A huge saving in time for those contractors or local authorities that have large numbers of pitches to mark out each week.
There are many types of material used around the world for line marking ranging from waste oil and other pollutants to dry powders to specialist line marking fluids for transfer wheel and spray markers, some of which can even be erased to make way for the next event on the pitch.
Specialist line marking fluid
Highly concentrated water-based paints, specially formulated for line marking, are the best selling products on the market for a number of reasons:
Economy - They can be diluted up to or above six parts water to one part paint.
Whiteness/Brightness - Excellent clarity can be achieved even at high dilution rates. Quality lines, displaying good colour and definition, can be produced on muddy pitches with only a sparse covering of grass.
Durability - These paints generally last up to 4 weeks or more, even in poor weather conditions, before remarking is necessary.
User friendly - these concentrates also have the following characteristics:
- Low viscosity and therefore easy to pour.
- Excellent storage stability. Greater than 6 months.
- Readily mix with water with little or no agitation.
- Diluted paint stays in suspension over the working day without settling.
- Equipment is easy to clean - requires only a rinse with cold water.
With the development of concentrated water based paints and spray marking machines the need to use herbicides, such as paraquat, or waste oil to burn lines by killing the grass has been eliminated. Such methods offer no advantage and often restrict the turf manager's options, ie. he/she will be unable to utilise a single sports ground for different sporting events. Furthermore, the use of herbicides and waste oils is not only harmful to the environment, but can also affect the health of the user.
Many caretakers use ordinary acrylic paint for marking lines. These products can contain high levels of solvent, some up to 25% by weight. These additives are classed as high VOC's (Volatile Organic Contents) and can damage turf as the solvent evaporates after application. Good quality line marking concentrates or house paints suitable for line marking are low in VOC.s and are classed as VOC.
compliant, conforming to the latest environmental standards. Paints used for line marking should have a VOC level of under 0.1%. This information can be found on the product's Material Safety Data Sheet (MSDS).
Not only can you get specially designed materials and machines, but there is also a vast choice of accessories in the line marking industry. Letter marking kits are a must for the novice turf managers and professionals alike. Stencils are becoming more widely used on sports grounds and pitches around the world, and with the advent of coloured pitch markers, it has become easy to create fantastic logos and messages on pitches.
Line marking machines also have a variety of attachments that result in more labour savings. For example athletic track marking boom attachments are available, as are spray booms and hand lances for agrichemical or fertiliser application.
HARD SURFACE MARKING
Not only have there been great changes in grass marking, but marking out on hard surfaces has also become easier and more effective. There are specialist VOC compliant paints and marking equipment for playgrounds, car parks, factory floors etc. that are colourful, hard wearing and non-toxic. The reign of the aerosol in hard surface marking is over!
About the Author
John Carr works for Fleet Australasia Ltd. He is based in Wanganui NZ.