Aug 01 2008

Is Catch Length Right For My Crew? (reader question)

Published by at 5:21 am under Other stuff

Recently James, from New Zealand, submitted this question:

I am interested in finding out the best way to set a crew up in the boat. I have for a long time measured back from the line of work a set distance and had all the crew set their back axel to this - to help with different length of legs etc. But now I am reading more and more about the need for a large catch angle. So, what is the best way to set the archs so everyone is rowing the same? Should I set an angle at the catch, but will this mean different finish lengths? Set it at the back and coach the catch length? What effect does Cord Length have?

First, thanks James for your question. It is a good one, that certainly should be of interest to anyone who wants to generate maximum hull speed for their boat, regardless of sweep or sculling.

Second, it would probably help to define some of terms, to make sure that we are talking about the same things (as you know, terms in rowing can be rather, er, strange.) You can find more rowing terms here.

The catch angle is the angle of the oar, at the catch, to a perpendicular line that runs down the middle of the shell. Catch length is a simple way to measure the catch angle, and is often used to really describe the same thing, from a non-angular perspective. The arch, or arc that you mentioned describes the theoretical track that the oar makes through the water. (I say theoretical because the blade really doesn’t move more than a small distance through the water, unlike the butt of the oarhandle which does make an arc.

The last term, cord length, is one seldom used here in the US. Basically it is the distance from the end of one point of the arc to another. It is not relevant to outside arc (how the blade travels through the water—because it doesn’t). Instead it is more relevant to the inside arc—specifically the distance of the inside arc. You might find this post on Oarsport helpful.

arc

Why Should You Care

For beginners coaches and Riggers (first and second Dimensional) this may all seem like hoopla. What difference does this make? A reasonable question. And a reasonable answer would be . . .”Speed.” It is all about speed.

Beginners, don’t worry about all the technically stuff here. It really boils down to this—where should I set my footstretchers? With that noted, zip to the end, and I’ll cover it there.

For you folks with more rigging under your belt, the reason you should care is still speed, but knowing how this works and all fits together will give you the tools to get more speed. The old ‘Teach a person to fish” saying applies here.

So how is all this information going to help you become a better Rigger? My rigging greatly improved when I realized most of the major adjustments I did when I rigged had an effect on the arcs. As soon as I grasped this concept, everything about rigging seemed to fall into place and I made the step from Second-Dimensional to Third-Dimensional Rigger.

Things Have Changed

There is not much change that has happened in rowing, or rigging, over the years but one place of some change has been track length. Used to be that rowers were concerned about running out of track, and hitting one or both ends. No more, in the last few years boat builders have been putting longer tracks into the boats, much longer than most rowers would ever use.
Another change I’ve noticed in the US is that the focus seems to be placed on the catch, and not as much on the finish. I know most of my peers rig to empahsize the catch, and the finish is a secondary thought. Don’t know if it is better or not, but that is what we seem to be doing.

So What Should I Do?

If the focus is all about speed what to do? I suggest:

  • focus on the catch angle
  • measure the catch angle by using catch length‚Äîor footstretcher placement
  • pay attention to the inside arc
  • pay no attention to the outside arc
  • accept a compromise between catch length vs finish length

How Do You Measure Catch Length/Angle
In a future post I will show how to measure the catch length and angle. Or you can read about  it in my book, Nuts and Bolts Guide to Rigging. In the meantime, if you are looking for a solution, you can get number suggestions here. Then set your tracks. And then set your footstretchers so that the seat wheels almost touch the front stops at the catch.

I hope that this is a productive start. Readers, send your thoughts along for James.

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