EVERYTHING
YOU EVER WANTED TO KNOW ABOUT RIGGING
BUT WERE AFRAID TO ASK
What’s it all about anyway?
Athletes come in different shapes and sizes, levels of fitness and skill. The same rig won’t suit them all, so we can either change the athlete to suit the boat or alter the boat to change the athlete. Things we can change are:
·
Stroke length
·
Catch position
·
Finish position
·
Blade depth through the stroke
·
Gearing
We
do this by altering
·
The stretcher
·
The riggers and pins
·
The blade length
The stretcher
Moving the stretcher backwards or forwards changes the arc of work:
In
sweep-oar rowing this arc (x + y) is about 90° and in sculling about 110°. In a faster boat (e.g. an eight) you want
more work in front of the pin, and in a slower boat (e.g. a pair) more work
behind the pin. You also want the
athlete to be comfortable in the boat, i.e. the outside hand should be able to
pull to the finish without having to bend the wrist out as the stroke comes in
to the body. Plus you want the whole
crew to finish at the same position, so it’s all a big compromise really.
Effect
of moving the stretcher forwards (for an eight):
Effect
of moving the stretcher backwards (for a pair):
You
can also adjust the height and angle of the footplate. The rower should be able to attain a vertical
shin at the catch, so the footplate should be set low down and at an angle of
42°. If the footplate is set too high,
the rower will not be able to achieve full compression and in addition the boat
will be less stable.
The riggers and pins
The main adjustment is the height of the work, which should be set so that the rower can pull in a straight line, producing a long stroke.
If the pin is set too
low, the rower will pull the oar in an arc, producing a shorter stroke:
The
height range will be 16cm – 19cm for sweep oar, 15cm to 18cm for sculling.
The
stroke length is also determined by the span (the distance from the centre of
the boat to the pin). The span should be
reduced for a shorter crew and increased for a taller crew in order to maintain
the correct angle and arc of work. In
sculling we measure the spread (distance between the two pins) rather than the
span.
|
|
Crew Height and Span/Spread |
||
|
|
Height (cm) |
Span (four) |
Spread (single) |
|
|
185-195 |
84-85 |
158-160 |
|
|
176-185 |
83-84 |
156-158 |
|
|
166-175 |
82-83 |
154-156 |
|
|
155-165 |
81-82 |
152-154 |
These figures are rather theoretical – in practice most coxed fours are
rigged with a span of 85.5 cm (half a cm less for coxless) and most scullers go
for a spread of 159-160 cm.
The span is also reduced as the boat speed increases – the span of a
double scull will be about 1 cm less and a quad about 1˝ cm less than a
single. An eight will have a span about
1 cm less than a four and 2 cm less than a pair.
Pitch
Pitch is the angle of the pin from vertical. There are two planes of movement:
·
Towards the bow or stern
·
Inwards or outwards
You
need some pitch to hold the oar in position in the water, since the oar is not
horizontal when you pull on it, but angled downwards. About 4° is normal, which used to be set by
having angled blades but these days is done using the plastic inserts in the
swivels. At the catch it is better to
have a little more to prevent the oar going too deep. At the finish you need a little less to make
it easier to hold the blade in the water.
So how do we achieve this?
1. You could try
setting stern pitch, but this will give less at the catch and finish and more
in the middle, giving a good finish, but a poor catch and drive. Setting the pitch towards the bow has the
opposite effect, giving a good catch but poor finish and drive. So this is NBG!
2. You could have
neutral pitch, giving the same angle throughout the stroke. Not much better!
3. Now for the
clever bit (someone with a degree in maths might be able to explain
this!). If you angle the pin outwards,
you really do get more at the catch and less at the finish. 1˝° of outward pitch gives you 5° at the
catch, 4° in the middle and 3˝° at the finish, assuming you are using 4°
inserts. Just right!
Blade length
Taller people need longer oars than shorter people. Seems obvious, but why? Because they have longer arms and legs! As we said above, the span should be set wider for tall people to achieve the same arc of work. This means the inboard of the oar will need to be greater so that they can reach right out to the catch and draw through at the finish. You don’t want less outboard as this will shorten the stroke length, so you need to start with a longer oar or scull.
Gearing
is the ratio of inboard to overall blade length. If it is too high, then rowing will be very
hard work, resulting in a “two part” stroke where the rower is unable to
maintain pressure through to the finish.
If the gearing is too light, the crew will have to take more strokes to
achieve the same amount of work, pushing the rating up which uses up
energy. So the level of fitness of the
crew also needs to be taken into account.
Because
cleavers have bigger spoons than
You
also need to adjust the gearing for the type of boat – rowing an eight is
easier than rowing a pair (you have seven people to help you) so you can cope
with a higher gearing.
So
the inboard depends on a number of things, but principally:
·
The rower (height, level of skill
fitness)
·
The type and span of the boat
Typical
inboard oar lengths are 114cm for an eight, 115cm for a coxed four and 116cm
for a coxless pair, and scull lengths 88.5cm for a single, 88cm for a double
and 87.5 cm for a quad. These lengths
are taken from statistics for international crews, who are generally tall with
long legs. Lesser mortals will require
shorter inboards!
Points to remember
·
All rig changes the way you row
·
Some rig changes are designed to
change the way you row
·
Adjustable rigging is for the
benefit of the athlete, not vice versa
·
Rig requirements will vary from
time to time (as you get fitter and more skilled)
·
All crew members do not have to
be rigged the same, but it is a good starting point.
·
Adjust one thing only, then try
it out
·
Keep a note of measurements, how
it feels/looks, how it affects the boat speed (do timed pieces)
Order of adjustment
Start
with the easiest thing first:
·
Stretcher
·
Slide bed
·
Spread/span
·
Height
·
Oar/scull
·
Pitch