designing a fast rowboat

rae photo

looking at the middle photo, in the middle ground from left to right: the yellow "last chance", race winner in my class. center of shot: red with a natural sheer, but looks like black in the photo; "The Red Baron, 2nd place. Upper right the translucent " Nordfijord Salt Cod Co. #1" (us) dead last in class .The rest of the boats are fours and sixes, we don't race against them directly. Classes are: work boat, single or double, livery boat ,single or double, multis (no cox) coxed 4's coxed 6's, sliders;single, double and fours, kayaks single and double and canoes, single and double. I think I got them all. Sometimes we have some traditional currachs come in as threes or fours, un coxed. most of the time we have beat them. We'll have to see what the weather brings. The local harbor-master always has the option of cancelling the race. He calls the shots that way.

 

weather up date

Forecasters are waffling a bit on if it will rain or not. they all seem to agree on a gusty N.E. wind. Sounds like a snotty day a best. The race starts at 10:30 so there's a chance that the wind may not have had a chance to build up too much. Hey, Charlie, are you out there? Haven't heard from you lately.

 

Hey, Jeff,

Wake up, that wuz me tellin' ya'll where to get carbon fiber and Kevlar cloth Monday.

Seriously, I think you "done good", finishing the race in a decent time pulling single oars after the blade plug broke (for want of a nail, etc.). As my beloved is fond of saying, "We always plan for the big things, but it's the little things that get us."

At least for classic designs, the old adage that if it looks good it will perform well seems to hold here. The 2 boats in your class that beat you are gorgeous, and yours has good lines, also. It will look great when the finish is done. Considering how you did after the mishap, you should be contenders this week if everything holds together (How are all the other wood plugs?).

 

a stitch in time

Sorry Charlie, must have been snoozing, as you said. all plugs have been replaced and we should be good to go. Weather is questionable; large storm moving off shore with STRONG N.E. winds predicted. Race may be cancelled or moved to Sunday. Check out the yellow boat. "The Last Chance" is truely wierd. I don't know if you can pick it out, but it has reversed chines. The chines rise as they get to the mid-section of the boat. Looks VERY strange, but obviously it rows well. That crew always does well no matter what boat they row. The other boat; "The Red Baron" is a work of art that was neglected by its original owner and has been resurrected by its current owners. It's traditional cedar on oak and very light. Rowed by father and son, the Robinsons, they always are right up there too. If they ever figure out that they have a couple of things they need to change, they will be even better. I don't dare even mention them here for fear it might get back to them.

CLint, Team Saquish keeps a site with race dates, How about sending them the info on your local race for next year

 

Jeff,

At first I thought the appearance of the yellow boat was caused by a shadow or reflection, but now I see what you're talking about. Seems odd at first glance, but maybe they are keeping waterline dimensions long and narrow for best hull speed, with more surface area for stability as the hull tilts.

I think I said I had and still have family in Maine, VT, and NH, so I know a little about Nov on the water up there. I have visions of boats full of icicle-covered people rowing desperately to the finish line and the hot cider/rum et al.

Good luck and strong oars!

 

small craft warning

20 KT. winds, gusts to 35. 4' high breaking waves. Harbormaster refused to grant permission to launch. A good call. most of the boats wouldn't have survived that, especially in the part of the race where we would have been broadside to the waves. We went into the North River and rowed a couple of miles to see how things would work in the boat. Wind was the same but far smaller waves due to being behind the sand spit. A couple of problems showed up: The stern was wildly out of control, blowing around terribly; at the finish of our pull, the oar handles are too far seperated and we're pulling almost sideways. A long, shallow skeg is definetly in order. Any increase in drag will be more than offset by not having to keep struggling to stay on course. Moving the oar buttoms out about 2" on the shafts should ease the rowing problem with the added benefit of lowering the "gear ratio" just a bit to lessen the effort needed to pull the oars. Looks like that is the last race of the year so we'll have the winter to finish the boat and also get a lot more time behind the oars to get back in our best shape for next March. Will stay in touch, Jeff

 

Hey, Jeff,

Sounds like fun!

You and bro seem to have things well in hand. Typical development of most any racing vehicle: work up a design based on past experience, build it, test, test, test, race, race, figure out what's not working, figure out a fix, make the fix, race, etc. etc.

Probably a good break to get to practice in nasty winds; finding out she won't track in the wind would not be fun to learn in a race!

Enjoy the holidays.

 

back to the future

Not done with one and yet thinking of another. I've got a CAD program and been toying around with it a bit. So far, not able to do much with it (PRO SURF) I'm told I need to load up a drafting program to draw what I've defined. I know that's another forum, but the point is that the gears are grinding still. A bead and cove strip built, glass sheathed in and out is my preferance for the next build. Traditional in appearance with the best possible underwater profile to maximize speed and reduce drag. Thinking of either eliptical sections or slight vee with hard bilges. how much rocker to have is also up in the air. Needs to have a nice hollow entry, but carry LCG about 40% aft of the bow to support our weight. I don't feel too attracted to building a surf-ski of a boat with raised bulwarks and large limber holes to free any water that comes in. Open to ideas and any drawings anyone may care to bring into the conversation. Optional plan is to take our original molds for the Nordvind, stretch them a bit and build in more beam. The original was good, and with the right changes could only be better. One thing we've noticed in our new boat is that we may have too much boat and maybe 18' would be better. time will tell as we get more time in with it and experiment with oars and other details.

 

"If you want to build a ship, don't drum up people to collect wood and don't assign them tasks and work, but rather teach them to long for the endless immensity of the sea." Antoine de Sainte-Exupery

Jeff,

Substitute "winning that damn long open sea rowing race" for "immensity of the sea" and that's you and bro. I chuckle, but I know the feeling. You've got it bad, but that's not a bad thing.

 

sickness

Charlie,

right you are. It is a sickness, but an exceedingly good one to have. The people we race against, and with, more importantly are a good group of people. Everyone from physicatrists to carpenters are out there enjoying themselves. There is NO money involved other than a race entry fee, usually $20.00 per person to support the organization sponsoring the race. After every race there are awards given out and usually a great feed is put on. Only once have I been the target of any hostility after a race because of who got beaten. I, on the other hand have been just a tad hostile on a couple of occasions. After one race where a coxed four passed us too close at the finish, tangled oars and cost us a place. I booted the fat cox in his rear end, and right into the bilges of his boat, delivering the message that he should abide by the racing rules of the road. Another time, I had a supply of nice smooth beach stones in our bilges and happily threw them at the big gigs that had been, up till that time, running down the smaller boats in the turns. No problem with that any more. One time, a gig tangled oars with us, and my brother got hold of two of their oars and just held on untill several other gigs passed. That was years ago, and racing is done with much more respect now. Great fun, and a thrill to be competitive at my age. Jeff

 

Sounds good so far.

Whoah there. 40% aft of the bow for your CB? That's way too far forward for low resistance. In fact you'd be hard pushed to find any boat with it that far forward. For low resistance you want it around 53-54% aft of the bow.

Why more beam? That's only going to slow you down. Also if you think you now have too much boat why stretch it so it's bigger? 20 feet should not be too long for a double. I can tell you for a fact that a sixteen foot waterline is way too short for a double.

 

CB etc.

Ok, 40% is too far forward, but consider that all our weight is centered forward of midships and we need the center of bouyancy as far forward as possible to support us with out a serious bow down attitude. A hollow entry might cheat the C.P. a bit to help ease things in the right direction. I guess I confused you with my ramblings. Our original molds are for a 9"6" boat with a 42" beam. to widen the beam to get enough room to pull a long oar, we pushed extra beam in at the gunnels and stretched the molds out to the 16" 8" length. This resulted in far too much rocker and an underbelly that dragged too much. Our idea is, since the molds are split to remove them from the finished hull anyway, seperate them to our desired beam and either add a flat panel as the bottom plank or to fair in the existing vee of the hull to the new bottom beam. This would get rid of the excessive rocker in the bottom and give more waterline length compared to LOA.Nordvind is 16" 8". Newest boat is 20' 3". Still need lots of time at the oars to find out if the 20' boat is OK or too much boat. A whole new boat is an option I'd like to consider in the bead and cove construction. A blank piece of paper might be a good thing.

 

Ok, the obvious question is why do you have your weight so far forward? To cut wave making resistance you need to put the CB aft of amidships. Putting in a hollow entry won't help support weight in the bow, because hollowing the entry removes buoyancy from the for'd sections. Just move your weight back to where it's best suited.
Yes, I think a blank sheet of paper is a good idea. A 20 foot waterline should not be too long for a double. Those 17' Herreshoff/Gardner boats have a 16' waterline and are slower with two crew than they are solo. The extra displacement jacks up the wave drag to the point where it outweighs the extra power.
If your boat is only 20'3" overall what's the waterline length? 18'? That's nothing, even for a solo boat.

 

weight distribution

we have found that if we center our weight in respect to LOA, our oars wind up so far aft that we have a very difficult time holding the bow into the wind, and that far too much effort goes into trying to stay on course. with the oars further forward, it is far easier to hold a course and put more effort into going fast in the right direction. This, unfortunately, puts our weight center far forward of midship. Hence the problem. Our LWL is about 18' 6", and we're finding that the boat is more manageable as we tune our oars length and spread as related to ratio of inboard to outboard. The most pressing problem is directional stability. there is no keel or skeg in place, and that will be changed shortly. Our theory was to build to a minimum and then add to it as necessary. We went out in 10/15 KTs this weekend and got blown around a lot, same as last weekend. despite that, we were able to get up to 6.1 KTS quite easily and hold it there for a while until we got way off course. this easily gets us in the realm where we can win races with the boat. not a perfect boat, but still it has the amount of improvement we are hoping for.
Another addition will be a spray rail. The boat isvery wet and holding the spray down a bit will be a good help for us mentally. I hate to row wet and cold, and waves slopping over the gunnels is distressing even if the amount of water being taken in isn't too significant.

 

the weather man lied! Thursday was sunny and warm, in the 60's. Brother was on his way north for the day so I gassed up my Triumph Bonneville and took a ride gor an hour. The roads were wet and a lot of leaves on them so caution was a must. Not rowing, but a good second choice. We're going to attatch a trial keel and skeg for Sunday AM to assess how much we need to stay on course. Out thought is to start just forward of midship with a shallow keel about 1" high and run it parralell to the waterline to form a skeg aft, then round it up to the stern, blending it in to look a bit like a rudder on a sailing faering. Should be a good test, forecast is for 40 degrees and a light to moderate breeze.