FINE TURF CYLINDER MOWERS UNDERSTANDING YOUR CYLINDER MOWER
A Precision Machine
TURF CONDITIONS ARE NOT PRECISE
AND CAN VARY GREATLY
SOMETIMES TO THE EXTREME 5
THE TYPE OF GRASS BEING CUT WILL VARY CUT WILL VARY
THE MACHINE AND IN PARTICULAR THE CUTTING UNITS MUST BE ADJUSTED CORRECTLY TO ACHIEVE THE BEST POSSIBLE QUALITY OF CUT FINE TUNING IS REQUIRED DEPENDING ON CONDITIONS
THE PRIMARY COMPONENT OF A FINE TURF CYLINDER MOWER IS? THE CUTTING UNIT IS THE PRIMARY COMPONENT
OBJECTIVES Understand the forces that influence the performance of the cutting unit Understand how these forces can be amplified by variable turf conditions
Understand why the mower needs to be adjusted to suit variable turf conditions OBJECTIVES Understand how to make Understand how to make the required adjustments
The Forces Acting On A Cutting Unit CAN BE Complex Some are very obvious Some are not Most are actually invisible
IN IDEAL CUTTING CONDITIONS Most forces have LITTLE or NO effect on the quality of cut IN THESE CONDITIONS.
WHEN TURF CONDITION VARY CUTTING UNIT FORCES ARE EXAGGERATED WITH A CHANGE IN THE CONDITIONS.
The Result CAN Lead To Quality of Cut Issues Turf Marking
If you understand what's going on You know what to expect And how to rectify the problem Or even anticipate it and make adjustments before quality of cut issue occur
UNDERSTANDING CUTTING FORCES Weight or mass of the cutting unit Rolling resistance Static balance Centre of gravity / weight transfer Ground pressure Torque reaction Gyroscopic forces
1. Weight or Mass of the Cutting Unit A number of factors can effect the weight/mass of a cutting unit. Number of reel blades Alloy or steel rollers Rear roller brushes Turf Groomer kit Weight can vary by X
How Does Weight Effect The Cutting Unit? Ground pressure Rolling resistance Unit sinkage into turf EFFECTIVE height ht of cut (HOC) Bedknife clearance
ROLLERS The roller is a major factor in the determining the quality of the finished cut. The roller type impacts on the HOC. Poorly maintained rollers will greatly increase the risk of turf marking. The incorrect choice of roller type can also result in turf marking problems reduced d cut quality. Seasonal changes, grass types, course layout and conditions should be considered. Different roller option should be considered for different times of the year.
ROLLER TYPES
GROOVED MACHINED STEEL Weight: 7.65 Kg General G l purpose roller, used on pedestrian mowers More aggressive than aluminium version Ideal for pedestrian models
GROOVED MACHINED ALUMINIUM Weight: 3.40 Kg General G l purpose roller, light weight. Even weight distribution well suited to triplex models Less aggressive, suited to new greens.
GROOVED SEGMENTED MACHINED ALUMINIUM Weight: 3.80 Kg Roller R section can rotate t at different speeds when turning Less aggressive, reduced marking on tight turns on perimeter cut
GROOVED ASSEMBLY STEEL DISC Weight: 4.08 Kg Wide spacing, very aggressive roller. Suited to Tees, Fairways and general Straight Line mowing
SOLID STEEL TUBE Weight: 3.45 Kg (smooth steel) Weight: 7.10 Kg (smooth steel solid) Solid: Tees units or basic units, closer cut. Solid: Used on pedestrian models, good ground following. Smooth: S h As above, good for wet winter conditions, i reduced d marking.
THE EFFECT THE WEIGHT OF THE EFFECT THE WEIGHT OF THE CUTTING UNIT IS DEPENDENT ON THE CONDITIONS OF THE TURF
FIRM TURF CONDITIONS LOW ROLLER LOW ROLLER PENETRATION
FIRM TURF CONDITIONS BEDKNIFE CLEARANCE MAINTAINED
FIRM TURF CONDITIONS EFFECTIVE HOC = BENCH SETTING
SOFT TURF CONDITIONS ROLLER PENETRATION HIGH
SOFT TURF CONDITIONS BEDKNIFE CLEARANCE IS REDUCED
SOFT TURF CONDITIONS BEDKNIFE CAN CONTACT TURF CAUSING INCREASED CONTACT WITH REEL
SOFT TURF CONDITIONS BEDKNIFE CAN CONTACT TURF CAUSING EFFECTIVE HOC IS NOW BLADES MUCH TO LOWER THAN RIFLE BENCH SETTING
Soft Turf Conditions (cont.) Effects Of Bedknife Contact On The Turf Excessive reel / bedknife contact Increased friction Increased heat Expansion of blades Harmonic vibration Bedknife rifleling Tramline turf marks Damage to cutting unit
SOFT TURF CONDITIONS (cont.) The increased friction between the bedknife and reel can be measured using a rolling torque wrench
Soft Turf Conditions TYPICALLY THE FORCE REQUIRED TO TURN THE REEL INCREASES FROM 0.6 Nm (5 Inch/Lbs) 0.6 Nm
Soft Turf Conditions (cont.) TO OVER 2.26 26 Nm (20 Inch/Lbs) 2.26 Nm A FOUR FOLD INCREASE!
KEY LEARNING POINTS When setting HOC allow for turf conditions Ensure clearance exists under bedknife when the unit is on the turf Select the correct profile bedknife for the HOC you require AND the turf conditions Don t forget contact between turf and bedknife will cause marks and damage to the blades
KEY LEARNING POINTS (CONT) CONTACT WITH THE TURF MUST BE AVOIDED
QUICK TIP If the underside of the bedknife becomes very polished from the leading edge all the way to the trailing edge HOC is TOO LOW Bedknife profile is TOO thick for the HOC and the turf conditions
GREENS BEDKNIFE PROFILE OPTIONS High Profile Low Profile Super Tournament Championship Height-of-Cut Range 4mm to 11.1mm 1mm recommended height of cut range 3.2mm to 5.6mm recommended height of cut range 2.1mm to 2.8mm recommended height of cut range 0.5mm to below Super Tournament Blade 1.6mm to 11.1mm, depending on turf conditions and bedknife installed
GREENS BEDKNIFE PROFILES Championship Bedknive Super Tournament Bedknive Low Profile Bedknive High Profile Bedknive
LOW ROLLING RESISTANCE
HIGH ROLLING RESISTANCE
ROLLING RESISTANCE PUSH FROM POWER UNIT RESISTANCE FROM TURF
ROLLING RESISTANCE FRONT ROLLER BECOMES PIVOT POINT ROTATING MOMENT IS CREATED
ROLLING RESISTANCE CENTER OF GRAVITY
ROLLING RESISTANCE SHIFTS FORWARD
EXAMPLE OF A SHIFT IN CENTRE OF GRAVITY
EXAMPLE OF A SHIFT IN CENTRE OF GRAVITY
ROLLING RESISTANCE WEIGHT IS NO LONGER WEIGHT IS NO LONGER EQUAL ON FRONT AND REAR ROLLERS
ROLLING RESISTANCE EFFECTIVE HOC WILL EFFECTIVE HOC WILL REDUCE
Variable factors are: RESISTANCE FROM TURF
Variable factors are: DISTANCE BETWEEN ROLLER AND UNIT PUSH POINT
Key learning points Rolling resistance is variable Soft turf conditions increase rolling resistance As rolling resistance increases, the centre of gravity of the unit shifts forward Weight is shifted on to the front roller Effective HOC is reduced. Weight transfer kits are available to to compensate
STATIC BALANCE WEIGHT ON EACH END OF UNIT EQUAL
STATIC BALANCE WEIGHT TO BALANCE HYDRAULIC MOTOR
KEY LEARNING POINTS Units must be statically balanced to avoid mismatch cutting issues Beware that accessories fitted to the units can cause imbalance unless correct balance weights are fitted. Example being Rear Roller Brushes. Stiff, twisted or incorrect specification hydraulic hoses can upset the static balance of the unit.
CENTRE OF GRAVITY
CENTRE OF GRAVITY
EFFECT OF TURNING DURING MOWING ON CENTRE OF GRAVITY DIRECTION OF TURN Inside end of roller becomes pivot point
EFFECT OF TURNING DURING MOWING ON CENTRE OF GRAVITY DIRECTION OF TURN C of G shifts to inside of turn
The inside end of cutting unit now has more weight more weight Effective HOC on inside of turn will be lower
In tight turns the effect is compounded
KEY LEARNING POINTS In soft turf conditions expect a step in the HOC on the inside id of the turn This is exaggerated on triplex mowers The step is due to the turf resisting the cutting unit turn Grooved front rollers may exaggerate the effect
GROUND PRESSURE EXPLAINED
GROUND PRESSURE EXPLAINED
LOW GROUND PRESSURE
LOW GROUND PRESSURE
HIGH GROUND PRESSURE
FOOTPRINT
TURF MARKING EXAMPLES TRAMLINING SCALPING WASHBOARDING MARCELLING STEP CUTTING GRAINING GRASS BROWNING OR YELLOWING MISSED STEM GRASS STEMS
TRAMLINING LINES OR UNCUT GRASS IN THE DIRECTION OF TRAVEL OF THE MOWER
TRAMLINING - CAUSES TRAMLINING IS CAUSED BY CONTACT BETWEEN THE REEL AND BEDKNIFE EXCESSIVE CONTACT CREATES HEAT BETWEEN THE METAL SURFACES DUE TO THE VARIATION IN MATERIAL THICKNESS THE METAL EXPANDS AT DIFFERENT RATES. THIS RESULTS IN HIGH SPOTS, AND RAPID DIFFERENCES IN THE WEAR PATTERN OF THE BEDKNIFE AND REEL. THIS VARIATION CREATES AREAS ALONG THE BLADE WHICH DO NOT CUT RESULTING IN THE UNCUT GRASS LINES. RESULTS IN HARMONIC VIBRATION PROBLEMS
TRAMLINING - CAUSES THE CAUSE OF THE REEL/BEDKNIFE CONTACT IS USUALLY AS A RESULT OF INCORRECT ADJUSTMENT BUT NOT ALWAYS!! CAN BE ONE OF THE MORE DIFFICULT CAN BE ONE OF THE MORE DIFFICULT TO RESOLVE.
SCALPING EXCESSIVE REMOVAL OF THE GREEN LEAF OF THE PLANT RESULTS IN HEAVY BROWNING OF THE SURFACE
SCALPING - CAUSES MOWING TOO FAST EXCESSIVE THATCH BUILD UP HEIGHT OF CUT TOO LOW FOR PLANT TYPE UNITS OR DECK NOT FOLLOWING UNDULATIONS
WASHBOARDING CUT APPEARS TO HAVE GENTLE ROLLING WAVE PATTERN IN DIRECTION CUT. RESULT OF VARIATIONS IN HEIGHT OF CUT
WASHBOARDING - CAUSES ROLLERS NOT TRUE (BENT OR OVAL) GRASS BUILD UP ON ROLLER REELS HOPPING DURING MOWING
MARCELLING OR RIBBING SHORT WAVY CUT PATTERN EXAGGERATED REDUCTION IN CLIP RATE PRODUCING CHOPPY FINISH NORMALLY THE CUT WAVES GREATED BY THE STANDARD CUTS PER METRE SPECIFICATION ARE INVISIBLE TO THE EYE ON A FINE TURF REEL MOWER. WHEN A PROBLEM OCCURS THESE WAVES BECOME VISIBLE.
Frequency Of Frequency Of Cut Explained
STEP CUT UNEVEN STRIPING EFFECT NOTICABLE DIFFERENCE IN HEIGHTS OF CUT WHEN CUTTING IN OPPOSITE DIRECTION.
STEP CUT - CAUSES UNITS NOT SET AT MATCHING HEIGHTS OF CUT UNITS NOT SET PARALLEL REELS NOT GROUND PARALLEL (CONICAL) UNEVEN PRESSURE ACTING ON DIFFERENT UNITS
MARKING GENERAL MARKS OR IMPRESSIONS ON TURF. NO VARIATION IN HEIGHT OF CUT SOME NATURAL DEFINISIONS OR MARKINGS CAN APPEAR DIRECTLY AFTER MOWING PARTICULARLY IN DAMP CONDITIONS
GRAINING GRASS GROWING IN ONE DIRECTION GRASS DOES NOT PRESENT ITSELF WELL TO THE BLADES FOR CLEAN CUT. TUFTING OR PATCHY FINISH
GRAINING - CAUSES MOWING IN REPEATED SINGLE DIRECTION CONSTANT TRAFFIC (BUGGY TRACK?) GRASS GROWING TOWARDS WATER SOURCE
GRASS BROWNING Grass that has developed a brown or yellow effect 24 hours after mowing. CAUSE: BLADES NOT SHARP GRASS LEAF IS TORN MISSED STEMS OR SEED HEADS FROM INCORRECT REEL/BEDKNIFE CLEARANCE. C
MISSED STEM GRASS Mowing finish satisfactory except for patches of missed grass stem or weed stems.
Thank You