Second rowing station for the V10.

Sail Boats 15' and up. Please include the boat type in your question.
terrulian
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Re: Second rowing station for the V10.

Post by terrulian »

If the trim is the big concer... what about a sand bag on the forward seat?
Trim is a big concern. This boat rows very nicely with one and just fine with three. But with two, being down at the stern means that the boat is sluggish. A sandbag at the bow would have to weigh 100 lbs. That won't do.
Tony
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Capt UB
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Re: Second rowing station for the V10.

Post by Capt UB »

terrulian wrote: Mon Jun 11, 2018 10:47 am Thanks very much, Jacques. Luckily, I'm short so that might help. Capt UB reports he managed it on his 6' dinghy.
I think I'm going to try it and report back. I will attempt to mount the new oarlocks temporarily somehow.
Bear in mind, this would be used only in the case where there weren't three on board and so the center seat passenger will not interfere with the rowing motion. My main concerns are the height of the bow seat, which is above the other two, and leg room. I have large holes in the center frame so maybe my toes can stick in there.

That dink was "PRETTY" and looked nice on the davits, it was far from a work boat! I had a RIB for the real work.
0121181617b.jpg
The RIB had oar locks, noway could you row that beast!

terrulian
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Re: Second rowing station for the V10.

Post by terrulian »

Yep, you can get into vicious arguments on cruising sites (not that I would do that) over hard vs. soft dinghies.

There is absolutely no question about aesthetics, but as far as I'm concerned, no argument about the practicality of an inflatable either. You really don't want to put five jerry cans of diesel in a hard dink and then have to row a mile in chop! Perhaps a nesting dinghy would work but it depends on how much deck space you have and if you think davits will work for you.

We had one with an inflatable floor so 1/2-way between a RIB and a soft dinghy. It would get up and plane with two aboard easily. It doubled as a very comfortable seat on the foredeck when deflated. Among the downsides of a soft dinghy is that as you say, they won't row, so if your engine dies you are hosed. That happened to me in Bora Bora in a bunch of wind but a very nice local came along and not only towed me back to my boat, when I offered him a beer he gave me one instead!!
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Re: Second rowing station for the V10.

Post by jacquesmm »

Image

This was a free plan listed on our website 2 years ago. It is designed by my grandson Thomas, a yacht designer and fluid dynamics engineer.
He worked hard on it to make it easy to tow behind a sailboat, have good capacity and ability to perform well with two rowing locations.
I think he succeeded.
It is also efficiently sculled with a single oar.
Note the pram hull which stays wider forward than the V10 pointy bow.
We discussed the beam, thwarts height, footrests, knee positions etc. and the minimum length was 10 to 11'. That would be a hull length of 14' with a pointy bow.

Image

Last week, I redesigned her for foam sandwich and tried to reduce her length. I could not go under the 10' while still being comfortable to row in the forward position.
Jacques Mertens - Designer
http://boatbuildercentral.com

terrulian
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Re: Second rowing station for the V10.

Post by terrulian »

Jacques,
The V10 tows fine, even in quite a bit of wind and chop. It is great in every way.
Tony
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Jaysen
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Re: Second rowing station for the V10.

Post by Jaysen »

terrulian wrote: Mon Jun 11, 2018 12:13 pm
If the trim is the big concer... what about a sand bag on the forward seat?
Trim is a big concern. This boat rows very nicely with one and just fine with three. But with two, being down at the stern means that the boat is sluggish. A sandbag at the bow would have to weigh 100 lbs. That won't do.
100lb? I'm not so sure. Now I know I'm dumber than your average box of rocks, but I think the same balance act for COG offset applies to V series as it does to the big monsters BUT since we are talking "water trim" we actually have a bit less as the hull is so much narrower on the bow of the Vs that it will drop much faster. I'm sure JM will call BS to that last part, but wide floats better than narrow.

I think the math is that for every lb/ft you have behind you need the same put front. Remember that a lb/ft is the weight/distance from COG. So a 200lb person 2ft aft from cog (rear seat) would need 200lb 2ft forward of COG or 100lb 4 ft forward or 50lb 8ft forward. In all that math you need to figure your weight as well.

The big assumption here is that the hull displacement is constant at all points. If the displacement DOES count, then the displacement forward will be < than the displacement aft. I believe this comes out to something like

Code: Select all

(weight - displacement)lb/(distance from cog)ft
This means that to counter a 200lb 2ft aft with a displacement of 150lb would only need countered by (200-150)lb/2ft = 50lb/2ft = 25lb/ft forward.

Like I said, I fully expect JM to call me all kinds of names and ban me from ever commenting on this topic again.
My already completed 'Lil Bit'. A Martens Goosen V12 set up to sail me to the fishing holes.
Currently working on making a Helms 24 our coastal cruiser.
“Mark Twain/Samuel Clemens” wrote:Eat a live frog first thing in the morning and nothing worse will happen to you the rest of the day.
Jaysen wrote: Mon Apr 29, 2019 3:44 pm I tried to say something but God thought I was wrong and filled my mouth with saltwater. I kept my pie hole shut after that.

terrulian
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Re: Second rowing station for the V10.

Post by terrulian »

Jaysen,
All I know is that with a 200 lb rower (not me, yet) and 150 in the stern and 150 in the bow, she's trimmed just fine.
This is empirical. Don't know nothin' about no math.
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Capt UB
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Re: Second rowing station for the V10.

Post by Capt UB »

terrulian wrote: Mon Jun 11, 2018 2:38 pm Jaysen,
All I know is that with a 200 lb rower (not me, yet) and 150 in the stern and 150 in the bow, she's trimmed just fine.
This is empirical. Don't know nothin' about no math.
:lol: :lol: :lol: :lol: :lol: + :lol: :lol: = :lol: :lol: :lol: :lol: :lol: :lol: :lol:

terrulian
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Re: Second rowing station for the V10.

Post by terrulian »

Here's the trim with a 200 lb person aft, 100 lb forward, 160 lb amidship (weights are rough approximations):
Image

Now with 200 lb amidship, 100 lb forward, 150 at the stern:
Image
Tony
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Jaysen
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Re: Second rowing station for the V10.

Post by Jaysen »

I guess it’s good I don’t have any friends (or spouse) willing to get into lil bit. Heck even the dog seems to look at her and say “are you nuts?”
My already completed 'Lil Bit'. A Martens Goosen V12 set up to sail me to the fishing holes.
Currently working on making a Helms 24 our coastal cruiser.
“Mark Twain/Samuel Clemens” wrote:Eat a live frog first thing in the morning and nothing worse will happen to you the rest of the day.
Jaysen wrote: Mon Apr 29, 2019 3:44 pm I tried to say something but God thought I was wrong and filled my mouth with saltwater. I kept my pie hole shut after that.

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