Rigging Questions
June Kendrick
I'm looking for things such as: if there is too much stern pitch, or too
little, what symptoms would appear, what does too much height cause (way
too little height I've learned means you scratch your thighs, have
trouble rowing square blades and have trouble in rough water, among
other things). What about heel cup height? Etc., etc., etc.
I'm doing rigging for a high school team, and am learning from Mike
Davenport's book, which is a great resource. It seems mostly geared for
how to make adjustments, and what ranges to use, but doesn't seem to
have much on why to use one end of the range over the other, or how to
tell when something should be moved.
Thanks for any suggestions.
Rob Plater
comfort of the rower.
You mentioned a couple of synarios, so here goes:
to much height: unable to maintain correct blade depth with washing out a
problem
heal height: effects the forward and back rotation. To high and the rower
will struggle to get enough length forward (shoulders in front of seat) and
tend to sit back too far. To low and too much length will be gained putting
the catch in a weak position and have trouble getting to the finish
position.
Blade pitch: it is v.important to have the same pitch on each blade to
ensure each blade is working the same weight - a balance of power must be
maintained. Too much pitch on one side will push the boat over to the other
side and also tend to washing out. Too little pitch will cause the blade to
knife making the finish difficult and pulling the boat down on that side.
Dirty finishes are a clue here.
Get it right the first time and it's easy from there.
Rob.
June Kendrick <7103...@compuserve.com> wrote in message
news:39DE95B4...@compuserve.com...
June Kendrick
adjustments.
I'm working with a High School team, with many kids and few boats, so we
never know who is going to be in what seat or boat. Given the large
differences in sizes among the kids, I just try to get average settings
that won't hurt anyone, and isn't grossly wrong.
My problem is that I'm at the point where I think I've got most of the
gross wrongs removed, and would like to better set the average numbers,
but don't really know what to look for to know which way to make any
adjustments.
Your comment on too much height causing washing out also implies that
too little height could cause a problem with digging?
Regarding blade pitch, if I've got a double that is down by port, could
it be that I might have too much pitch on starboard, and/or too little
on port? By how much: 1/2 degree, 1 degree, more?
If I've got adjustable seat tracks and riggers that adjust fore and aft,
along with foot stretchers that move, where should I put the oarlock
pins, foreward, aft of or even with the main brace knee?
Thank you for your help. I'm finding this interesting and am trying to
learn, but as I'm not a coach and am not on the water with the kids,
it's not easy.
June
Anu Dudhia
> Your comment on too much height causing washing out also implies that
> too little height could cause a problem with digging?
Too little height and people can't get their finishes out because they're
scraping their hands on their thighs. If they can't row square blade, the
height is too low. If in doubt, rig too high rather than too low.
> Regarding blade pitch, if I've got a double that is down by port, could
> it be that I might have too much pitch on starboard, and/or too little
> on port? By how much: 1/2 degree, 1 degree, more?
It would have to be pretty extreme (and people pulling very hard) before
you notice the effect on the balance. More likely the oar digs/washes out
if the pitch is more than a couple of degrees out. Only very experienced
rowers would notice a difference of 1/2 degree, and +/-1 degree is about as
accurately as any two people will agree when measuring the same pitch in
any case.
> If I've got adjustable seat tracks and riggers that adjust fore and aft,
> along with foot stretchers that move, where should I put the oarlock
> pins, foreward, aft of or even with the main brace knee?
The relevant adjustment is the position of the stretcher relative to the
pin, which is best left to the rowers to set themselves as it very much
depends on the individual's height. Slides can be positioned to fit the
tallest person (so they can get their legs down flat) and the position of
the whole lot relative to the hull doesn't really matter.
Typically, reasonable flexible rowers should be able to row and arc of
around +45 deg (catch) to -30 deg (finish) at the pin (defining 0 degrees
as perpendicular to the boat length).
Rob Plater
accuracy of the finish. What you need to do in regard to pitch is set all
the boats the same so the rowers don't have to get used to a new rig each
time the change seat or boat. Set all the riggers in the middle position.
The feet should be set by the rowers (for sculling the handles should just
scrape past the body at the finish position and for sweep the outside wrist
should be straight and close to the body). Adjust the slides so as no to
restrict the rower.
Pitching:
The best way to do this is to get two sprit levels. One to keep the boat
level with someone holding it (check the boat is also level from bow to
stern before starting). Hold the other level against the naked pin (i.e.
remove the gate and all washers).
The aim is to get all the pins vertical.
Once this is achieved make the pitch on all the gates the same. This is
actually quite easy to do by replacing the inserts or wedges to 4-4 or
number 0 respectively. This sounds a little cryptic from this end, but it's
ok, have a look at the gates and it will become clear.
Once you've set all the pitches then you can worry about making everyone
comfortable with heights.
I hope this helps not hinders,
Rob.
June Kendrick <7103...@compuserve.com> wrote in message
news:39E1286B...@compuserve.com...
Jeremy Martin
for individuals rowers within a crew, instead of being uniform. Rig for
comfort rather than conformity.
Last year I rowed a double with a friend who is significantly shorter than
me. When we first rowed together I felt very rushed, because my blades
were in the water for longer than my crewmate.
So we measured our respective reaches, using an ergometer and a
tape-measure, and then performed a simple trigonometric calculation to
set differing spans so that we would row the same length of stroke in
the water (with a suitable inboard adjustment on the sculls to fit).
The result was that my crewmate's span was set to around 155cm, whereas
I was on 162cm. My partner was concerned that he would have to do all the
work since he had a very hard gearing and mine was soft. But in fact it
felt incredibly much more comfortable, and we went significantly faster.
The gain in speed would be explained partly be the increased comfort and
partly because my oars were no longer tearing through the water. We were
able to lock on together, lever the boat along, and then finish together.
So now I would ask: why insist on everybody having the same rig? If you
do you may be throwing power away. Rig for each individual so that he or
she may row in an optimal way according to his or her physical limitations
(very much the Steve Fairbairn philosophy). You could also measure hand
heights on the ergo and set the boat accordingly. For crew sculling it
might also make sense to allow variation in the height difference between
bowside and strokeside across the crew.
This is an example where some very simple mathematics can potentially
make a lot of difference. I wonder how many international crews
use this kind of fine adjustment.
Jeremy Martin
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Dr J. M. R. Martin
Oxford Supercomputing Centre Tel: (01865) 273849
Wolfson Building Fax: (01865) 273839
Parks Road Email: jeremy...@comlab.ox.ac.uk
Oxford OX1 3QD WWW: http://users.ox.ac.uk/~jeremy
Carl Douglas
Rob Plater <r...@dutchie.net> writes
>The most common reason for a boat being out of balance is timing and
>accuracy of the finish.
Very true. But remember that some of the problems at the finish can
come from over-zealous extraction. The finish should be very hard, but
blades should leave the water smoothly, easily, together and *unloaded*.
Otherwise the boat will be edgy & unstable, there & for the entire
recovery.
> What you need to do in regard to pitch is set all
>the boats the same so the rowers don't have to get used to a new rig each
>time the change seat or boat. Set all the riggers in the middle position.
>The feet should be set by the rowers (for sculling the handles should just
>scrape past the body at the finish position and for sweep the outside wrist
>should be straight and close to the body). Adjust the slides so as no to
>restrict the rower.
>
>Pitching:
>The best way to do this is to get two sprit levels. One to keep the boat
>level with someone holding it (check the boat is also level from bow to
>stern before starting). Hold the other level against the naked pin (i.e.
>remove the gate and all washers).
Better still, since it's hard to hold a boat still unaided, chock the
boat level with a couple of inclined sticks, one each side, from the
ground to the rigger bolts or the lip on the sax.
>
>The aim is to get all the pins vertical.
Which, unless you have our AxioR pins, can only be done by bending pin
&/or rigger - which is no way to treat essential kit!
Generally you require zero stern pitch, but sound cases can be made for
adopting between 1 & 1.5 degrees outward lateral pitch.
>
>Once this is achieved make the pitch on all the gates the same. This is
>actually quite easy to do by replacing the inserts or wedges to 4-4 or
>number 0 respectively. This sounds a little cryptic from this end, but it's
>ok, have a look at the gates and it will become clear.
However, do not overlook the possibility - as nearly everyone mistakenly
does - that the oars themselves may be off-pitch. (Everything made &
used by Man is susceptible to error, especially after time).
You can get a very useful check on pitch by taking a pair of oars at a
time, putting then side-by-side at the pulling face of the sleeves on a
horizontal bar (e.g. a trailer or clubhouse boat rack bar), holding the
handles side by side so that they are supported only on the sleeves, and
then carefully & slowly making a visual comparison between the 2 oars:
1. Do the spoons look to be pitched equal & opposite (swap the oars from
side to side until you are sure)?
2. Are the shafts straight in both the vertical (pulling) direction &
sideways?
3. Are the spoons identically aligned, or is one either drooping or
angled sideways.
Manufacturing standards are high, so normally there will be no problems,
but just occasionally you'll spot trouble this way which, otherwise,
would never have been identified.
>
>Once you've set all the pitches then you can worry about making everyone
>comfortable with heights.
>
>I hope this helps not hinders,
>Rob.
>
Cheers -
Carl
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing low-drag Riggers/Advanced Accessories
Write: The Boathouse, Timsway, Chertsey Lane, Staines TW18 3JZ, UK
Email: ca...@carldouglas.co.uk Tel: +44(0)1784-456344 Fax: -466550
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)
Beverly Shelton
> sound cases can be made for
> adopting between 1 & 1.5 degrees outward lateral pitch.
> Cheers -
> Carl
I'm just a neophyte recreational rower, but the used Maas 24 I picked up
last spring just didn't feel right. The pins had too much outboard pitch.
Shimming them to 1 - 1.5 deg. made a huge difference. (Those throw-away AOL
cd-roms make good shim stock.)
Ken Shelton
edgar cove
<ca...@carldouglas.co.uk> writes
>However, do not overlook the possibility - as nearly everyone mistakenly
>does - that the oars themselves may be off-pitch. (Everything made &
>used by Man is susceptible to error, especially after time).
>You can get a very useful check on pitch by taking a pair of oars at a
>time, putting then side-by-side at the pulling face of the sleeves on a
>horizontal bar (e.g. a trailer or clubhouse boat rack bar), holding the
>handles side by side so that they are supported only on the sleeves, and
>then carefully & slowly making a visual comparison between the 2 oars:
>1. Do the spoons look to be pitched equal & opposite (swap the oars from
>side to side until you are sure)?
>2. Are the shafts straight in both the vertical (pulling) direction &
>sideways?
>3. Are the spoons identically aligned, or is one either drooping or
>angled sideways.
>Manufacturing standards are high, so normally there will be no problems,
>but just occasionally you'll spot trouble this way which, otherwise,
>would never have been identified.
This is good advice and I would only add that the horizontal bar that
you use should not be too wide as the area of the sleeve that comes into
contact with the swivel is only about 2cm from the button. This is the
part that wears and if your bar is wider than this you will be locating
on the unworn part of the sleeve which probably started off at zero
pitch and your result may therefore be misleading. Best to put a piece
of wood or metal on the bar which is accurately 2 cm square and rest the
blade on this as near the button as possible. Then you can zero your
pitch gauge on the bar and then transfer it to the blade to get an
accurate pitch.
But the visual inspection that Carl advocates is essential as without it
it is easy to make a mistake as to whether the pitch is positive or
negative. My sculling blades started out both on zero but now one is 2
degrees positive and the other 2 degrees negative and I have no idea why
this happens. I suppose I could file them back to zero but I simply
tweak my Axior system so the net result is what I want. ;-)
--
edgar (remove nospam from return address for e-mail reply)
Ewoud Dronkert
> (Those throw-away AOL
> cd-roms make good shim stock.)
:). That's between the shell and rigger I guess? Problem is the height
will change too, and sometimes out of the desired range. For riggers
without a pitch adjusting system (eg Empacher or Filippi or maybe most
except Aerowing) I always use some small rectangular pieces cut from a
soda can to put next to the pin under the washers. Gives about one
degree change.
Ewoud
Triton Utrecht
Rob Plater
written. Remember who asked the question in the first place, a humble school
coach with limited experience. It's actually quite hard to get a 1 degree
camber on the pin without the write equipment. Yes you may need to bend the
pins to get it right, but done once correctly and you shouldn't have to
worry about it in the future.
I sure we could all wirte our own books on how to rig a boat, I reckon I
could write a completly new book for each type of boat, but lets try to keep
it simple. Rowing is a fairly simple sport.
June Kendrick
Does Ruden actually discuss all this? If so, I'll go get a copy.
It should be noted that I'm not actually a HS coach, but just helping
one out. He knows less than I do about rigging.
The comments about individually tuning are great, but in a HS
environment where the same seat may be rowed by a number of different
sized kids in a week, I'm doing good if I can just get the rigging so it
doesn't hinder or hurt the kid. Last year, we had a four that was
stroked in one race by a boy 6'2" and 250, and in the next one by a girl
5'6" and 120#, with no time between to adjust rig. We gave the girl a
seat pad or two and said have fun, while the guy could barely get the
oar over his knees.
Fortunately the program is intended to give the kids some experience and
have fun, not to be highly competitve, though we do have our share of
serious kids.
For the sweep boats, I figure that if I can keep the pitch somewhere
between 4-7 degrees, aiming towards 6, and the height so that the kids
can get the oar over their knees and below their armpits, I'm doing ok.
The sculls are a bit more interesting, as most of ours come in with the
coach saying that they are digging to port and we haven't yet figured
out whether it is the rigging or kids or boat. If it's the rigging, the
question is height, pitch, span or what? On one boat, we know its the
boat. It was dropped this summer, and the deck is now not quite
centered over the hull, so it doesn't even float evenly at the dock.
Thank you again for your help.
Rob Plater
lighty girls in the same seat. Unfortuantely there's not much you can do,
but what you did (seat pads) was spot on. Many of my rowers where ther
runners in the boat and still fit into the guys foot straps.
It's really hard to diagnose a problem like off pitch etc, but it is fairly
easy (and not so time consuming after a bit of practice) to get right,
therefor removing the problem. A poor workman blaims his tools, and it goes
the same for rowers, never have the boat in a condition where it could
possible effect the rowing.
Anyway, enough from me. Good luck and I hope you get you share of medals
this season.
Rob.
June Kendrick <7103...@compuserve.com> wrote in message
news:39E7C103...@compuserve.com...
edgar cove
<7103...@compuserve.com> writes
<snipped>
>The sculls are a bit more interesting, as most of ours come in with the
>coach saying that they are digging to port and we haven't yet figured
>out whether it is the rigging or kids or boat. If it's the rigging, the
>question is height, pitch, span or what?
It is most likely the pitch and the two sculls should have the same
pitch (final pitch relative to the water) within 1 degree of each other
if the sculler is to feel comfortable. Do not assume that because port
is digging that port is at fault-it may easily be that starboard does
not have enough pitch and the effort of keeping starboard buried is
forcing port down.
> On one boat, we know its the
>boat. It was dropped this summer, and the deck is now not quite
>centered over the hull, so it doesn't even float evenly at the dock.
>.
We need more info here, I think. Do you really mean that it is the deck
that is not centred over the hull? How can this be?
June Kendrick
soft single skin, and had a bad dimple in the hull when I found it -
about 1 foot square, in the bottom of the boat, about even with the aft
end of the deck area. It hasn't balanced right since then, even with
nobody in it. We popped the dimple out, but that hasn't helped. The
sad part is that it was sent back to the factory last winter and was
rowing real nice this spring. It looks like the deck is about 1 cm off
to one side when you look at it.