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Red Hudson

This morning, I took out the red Hudson, stored just above the blue Hudson I'd used previously. It was much nicer in key ways. The footstretchers hold my feet at right about the correct spot, and the tracks are much smoother. It also has a holder for a Stroke Coach, which means I can use the older model stroke coach that dichroic gave me a while back to do timed workouts with known stroke rates.

For some reason, though, it felt like the spread was way off for my starboard oar. Either that or my posture changed dramatically between Saturday and this morning. The handle was a good inch closer to my ribcage than the port oar handle. That made steering interesting, too.

I got in about 10 good strokes over the course of the morning, but at least for those 10 strokes, I could feel that sensation of the boat moving well. The red Hudson should be the correct weight class overall - 160 to 190 pounds. I'll row it again.

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( 8 remarks — Remark )
randomdreams
Mar. 2nd, 2016 03:12 am (UTC)
Are the oarlocks adjustable? Are the points where the seat attaches to the rails adjustable? That's really odd.
rebeccmeister
Mar. 2nd, 2016 06:32 pm (UTC)
There are a lot of aspects of the oarlocks that are adjustable - both pitch and "spread" in particular (distance of the oarlock from the center of the seat).

From visual inspection, the spread looked fine/even (both oarlock pins were in approximately the same place in either rigger). Another rower wanted the boat immediately after I finished using it, so I didn't have time to measure the spread, though. I told her about my experience, and she said she'd check it, but methinks I'll double-check it again on Thursday morning. I was also noticing some differences in leverage between my right and left arm, which would correspond with incorrect spread.

I'm pretty sure the pitch was all right - that mostly affects the angle of entry and exit for the oar, and usually if the pitch is way off it's pretty obvious. And I know the oars were okay, because I've been using those oars in the Maas and the blue Hudson without any problems.
randomdreams
Mar. 3rd, 2016 01:31 am (UTC)
Hmmm, weirder yet.
I'm assuming (maybe incorrectly) that the oarlocks are fixed on the oar shafts? The ones I used, the oarlock was D-shaped with the straight part of the D going through a hole in the oar shaft, but now that I think about it I can see a bunch of utility in having that an adjustable item to help change leverage.
rebeccmeister
Mar. 3rd, 2016 01:46 am (UTC)
Here's a Wikimedia photo of the oarlock:
https://en.wikipedia.org/wiki/File:Rowing_Sport_Oarlock.jpg

And here are two oars:
https://en.wikipedia.org/wiki/File:Croker_Sculling_Oars.jpg

The hot pink portion on the oars are the "sleeves," and the greenish pieces on the sleeves are the collars or buttons. The buttons are adjustable, to change the outboard oarlength. Some oars also have a separate adjustment mechanism for changing the inboard independently of the outboard. The best inboard/outboard and overall oar length depend on the rower's biomechanics and the characteristics of the race. A lighter load will be better for a longer event, but on the other hand it will translate into less power application per stroke.

The angle of the oarlock on the rigger, along with the positioning of the collar on the oar (usually carefully standardized), together determine the pitch of the oar blade when it's in the water. In addition, you can see from the photo of the oarlock that the pin attaching the oarlock to the rigger can be moved closer to the boat or further away, affecting the spread. It's also possible to make vertical adjustments of the oarlock, which will adjust the oar height.

in a nutshell, lots of little fiddly bits to optimize... :^)
randomdreams
Mar. 3rd, 2016 04:31 am (UTC)
Oh, yeah, unsurprisingly totally different than what I had. That's neat!

Okay, so, pitch of the oar blade in the water. My initial presumption was that you'd want it normal to the water surface, both to minimize drag and to maximize water acceleration -- but that anticipates an unmoving medium. So presumably you want it to cut in at an angle dependent on speed, to minimize entry/exit drag? How does that affect the angle during the power stroke?

My biking experience immediately makes me think more strokes per minute == more power, but that seems to be a lot more biomechanical than pedaling is.
rebeccmeister
Mar. 7th, 2016 09:30 pm (UTC)
So, I suspect there's some slightly more complex geometry involved, but the leading experts on the subject are one of the major oar manufacturers, a company called Concept2. They say a 2-degree pitch is ideal, and I am just going to take their word for it. I *do* know that it's hard to get good leverage through the water with an over-pitched oar, and that it's really hard to get an under-pitched oar out of the water at the end of a stroke. They have a cool diagram of what's involved at the bottom of this page:

http://www.concept2.com/service/oars/pitch/checking-and-setting-pitch-sleeve
randomdreams
Mar. 8th, 2016 01:42 am (UTC)
I'm suddenly struck by the thought that this might be a good place to swap flat plates for aerofoils. I was thinking about a hummingbird-wing-movement oarlock that varies pitch as a function of linear displacement. (I recall reading about rowers who twisted their oars during paddling, similar to how free-oar rowers like canoeists do.) That makes me wonder if there is a way to make oars like airfoils, the way sailboat sails are beginning to shift: double-surface and relying on lift rather than just displacement. It's much harder to do with the movement of an oar blade than windflow across a sail, though.
( 8 remarks — Remark )

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