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RIGGING BOAT EQUIPMENT
BOAT PARTS
! Wave breaker ! Rigger (fifth rigger) ! Oarlock ! Axle ! Seat ! Footboards (heel) ! Slides
BOAT SHAPE AND SPECIFICATION
! Shape ! Specification ! Boats Weight Length
8+ 96 kg 16,5-18,5 m
4+ 51 kg 12,0-13,7m 4- 50 kg 12,0-13,4 m 4x 52 kg 12,8-13,8 m 2- 27 kg 9,8-10,4 m 2x 27 kg 9,8-10,4 m 1x 14 kg 7,30-8,30 m
BOAT RIGGING
! Spread and Span ! Internal shaft ! Oarlock height (water-oarlock; seat-
oarlock) ! Angle (total angle = oarlock angle +
paddle angle) ! Footboard angle, height and position
Spread and span
a
b
d
e
Spread and span sweep boat Spread and span scull boat
c
Internal and external oar shaft
! Adjustment of oar to new length also requires the adjustment of the internal shaft
! Internal shaft for sweep boat = span + (28-30 cm)
! Internal shaft for scull boat = span /2 + overlap ! Overlap: 16 – 22 cm (oarlock 2 cm)
Standard measures for heavy rowers
Boat Span Internal shaft Oar length cm cm cm
1x 159-162 88-90 288-292
2X 158-162 87-89 288-290 4x 156-158 87-89 288-290 2- 86 116 372-376 4- 85 115 372-376 8+ 84 114 372-376
HEIGHTS ! Height between seat and oarlock sweep– 15 - 18 cm
scull – 14 - 16 cm (difference L –D ; 0,5 – 1,5 cm)
! Height between water surface and oarlock SWEEP – 26 CM
SCULL – 26 CM Is rower comfortable? Are rower’s fists at the same height as his shoulders? Is there sufficient space to finish the pull cleanly and smoothly? Do blades sink or get out of the water at the end of the pull?
! Height from water surface to roll.
Angle
! Angle on oarlock Optimum angle is a matter of personal preference. More experienced rowers prefer smaller angle. Slower boats require smaller angle than faster boats.
sweep - beginners 5-8 degrees; others 0-4 degrees scull - beginners 4-6 degrees; others 0-6 degrees
! Angle on oar Angle on oar is usually 0.
Total angle of blade in water = angle on oarlock + angle on oar
Angle
! Angle on axel - Vertical axel - Inclined axel Lateral angle
Footboard angle, height and position
! Measuring footboard angle ! Measuring footboard opening ! Measuring footboard height ! Footboard position
BASIC RIGGING SUMMARY
RIGGING STANDARD MEASURES
span sweep table: 3.1,3.2,3.3 & 3.4 ( soon in our shop )
span scull table: 3.1,3.2,3.3 & 3.4 ( soon in our shop )
sweep = span + (30-32 cm)
Internal oar shaft scull = span /2 + overlap/ 2
table: 3.1,3.2,3.3 &3.4
Height of oarlock from seat sweep - 15-18 cm
scull - 14-16 cm
Height of oarlock from water sweep - 26-27
scull - 26 cm
BASIC RIGGING SUMMARY
RIGGING STANDARD MEASURES
sweep - beginners..........5-7 degrees
- others...............0-4 degrees
Angle on oarlock
Scull - beginners 5-8 degrees
- others 4-6 degrees
Angle on oar Usually 0 degrees
Footboard angle 40-45 degrees
Footboard opening angle 25 degrees
BASIC RIGGING SUMMARY
RIGGING STANDARD MEASURES
Footboard height 15-18 cm
Angle between axel and bow
Approximately 32 degrees for sweep
Footboard position Tall rowers - 65 cm
Medium heigh rowers - 63 cm
Short rowers -60 cm
Back angle in scull -35-40 degrees
THE GEARING RATIO
Calculating gearing ratios for “cleaver”
(oar length (cm) – internal shaft (cm) – centre of pressure span (cm)
E.g. Oar length 376 cm (376 – 117) – 26 = 2.74 Internal shaft 117 cm 85 span 85 cm Centre of pressure (CP) sweep 26 cm
scull 20 cm
CHANGING THE GEARING RATIO
Changing the gearing ratio by changing the internal shaft and span.
Example:
oar length 376 span 83.5 internal shaft 113.5 By changing the shaft from 113.5 to 114.5 the gearing ratio changes from 2.83 to
2.82. The difference is 0.01
CHANGING THE GEARING RATIO
If shaft is left at 114.5 and span increased by 1 cm i.e. from 83.5 to 84.5 cm, the gearing ratio will change from 2.82 to 2.79.
The difference is 0.03
CHANGING THE GEARING RATIO
Changing the gearing ratio by changing oar length
Example:
oar length 376 span 83.5 internal shaft 113.5
If at this gearing ratio configuration oar is lengthened by 3cm, the gearing ratio will increase from 2.83 to 2.87.
The difference is 0.04
CHOOSING THE GEARING RATIO
! Shorter race – higher gearing ratio ! Stern wind –higher gearing ratio ! Bow wind – lower gearing ratio ! Stronger and fitter rowers - higher gearing ratio ! Shorter pull – higher gearing ratio ! Higher pull frequency – lower gearing ratio
GEARING RATIO CONFIGURATION
Faster boats – higher gearing ratio Faster boats – shorter span Faster boats - longer external oar shaft
Scull boat gearing ratios are lower
- Scull boats are 2.17 - 2.38 - Sweep boats are 2.55 - 2.95
APPROXIMATE GEARING RATIO FOR SENIORS
Seniors Span +
cm Internal shaft
cm Oar length
cm Maximum
gearing ratio
1x 159 87 288-292 2.33
2x 159 87 288-292 2.34
4x 157 86 288-292 2.38
2- 86 115 374-378 2.79
4- 85 114 375-379 2.85
4+ 85.5 114.5 376-379 2.82
8+ 84 113 376-379 2.89
MECHANICAL PRINCIPLES
PULL EFFICIENCY IN RELATION TO ANGLE
- X ; PROPULSION IS GREATEST WHEN OAR IS VERTICAL TO BOAT - Y ; TORQUE IS GREATEST DURING GRASP AND AT END OF PULL
Y
X
B
B
Propulsion and torque percentages at several angles
Oar angle before and after axle
(vertical)
Propulsion in percentages in relation to total force (y %)
Torque in percentages in relation
to total force ( x %)
58 Grasp 45.62 55.38
45 Grasp 50.00 50.00
35 Grasp 58.81 42.19
20 Grasp 73.31 27.69
0 100.00 00.00
20 End 73.31 27.69
35 End 58.81 42.19
45 End 50.00 50.00
50 End 45.62 55.38
GRASP AND END LENGTH
Rower’s physical dimensions (arms, legs, body) Boat and equipment gearing ratio configuration Specificity of technique prefered by the coach Crew size and shape – desire to have rowers from
the same crew row with equal length and parallel during pull and in the return stage
Beginners Others Grasp End
Sweep 80-85 85-100 45-60 35-40 Scull 85-100 95-110 55-65 35-40
MEASURING PULL LENGTH AND ANGLE
Grasp End
z k Oarlock
Bow Centre line
GRASP VALUES ( sweep )
angle 82 82.5 83 83.5 84 84.5 85 85.5 86 86.5 87
45 82.00 82.5 83.00 83.5 84.00 84.50 85 85.5 86.00 86.50 87.00
50 97.72 98.32 98.92 99.51 100.11 100.70 101.30 101.89 102.49 103.09 103.68
55 117.11 117.82 118.54 119.25 119.96 120.68 121.39 122.11 122.82 123.53 124.25
span
Grasp
PULL END VALUES ( sweep )
angle 82 82.5 83 83.5 84 84.5 85 85.5 86 86.5 87
30 47.34 47.63 47.92 48.21 48.50 48.79 49.07 49.36 49.65 49.94 50.23
33 53.25 53.58 53.90 54.23 54.55 54.87 55.20 55.52 55.85 56.17 56.50
35 57.42 57.77 58.12 58.47 58.82 59.17 59.52 59.87 60.22 60.57 60.92
span End
BOAT MODIFICATIONS DEPENDING ON WEATHER CONDITIONS
Adjusting to bow/stern wind Lifting oarlocks on rough water Using tape and other materials to prevent
entry of water into boat In strong wind, put lead tapes on oar body
end (by the blade)
ITALIAN AUSLEGER FORMATION
! Possible boat formation variations
ADVANTAGES OF ITALIAN FORMATION
Lateral distance of the boat due to unequal pressure on oarlock
ADVANTAGES OF ITALIAN RIGGER FORMATION
A B
a) Normal rigger formation and (b) Italian rigger formation