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Sandy's Take on WW Dories

Posted by MikeInBoise 
Sandy's Take on WW Dories
November 05, 2015 05:27PM
Sandy & all you other decked dory folks,
I was perusing the phorum and Sandy's GC Droy page and thinking about design considerations for a decked white water dory in the 17'-18' foot range. Sandy speaks to upsizing the HD to about 17' with a 60" bottom and more flare. All of this sounds great. I am jonesing to get a project like this going even though I am just to the paint stage on my HD. I also realize Sandy is working in his shop with a "full scale model" currently. I am waiting with baited breath to see his final specs. Given the upsized HD dimensions above and a 60" bottom and "more flare", what would this mean in terms of beam at the oarlocks? What is too much beam in the world of WW dories? 85"? 80" about right?

Another item, I am strongly considering is a sizeable flat section in the center of the bottom while maintaining 12" -14" of rocker at the bow and stern. Thoughts about having a flat vs a continuous rocker in WW droies? Thoughts on length the dish in the chine? 25%-33% of total length or is that outlandish?

I like chord lengths of the front stations on the HD as it gives the dory some "shoulders" up front. Those station dimensions yield some really pleasing lines. Upsizing the HD to 17-18' with a flat in the middle while maintaining the rocker, flare, "shoulders" and raising the freeboard at the oarlocks is really appealing.

You have any recent pictures of your plug Sandy?

Thanks,
MikeInBoise
Re: Sandy's Take on WW Dories
November 06, 2015 01:47AM
Lots of good questions.

How much is too much beam? Good question. I don't know. AJ DeRosa has several boats designed by Cyrus Happy (Ray Heater's partner) made from 20' foot side panels. Those boats are about 69" wide under the oarlocks. I measured the beam and have it somewhere. Or maybe I lost it. It has six passenger seats in two rows of three, immediately in front of the rower.

I have rowed that boat, albeit with no passengers. It rows a thousand times better than the Briggs.


Flat spots? I do not like flat spots. A 4' foot or 6' foot section in the middle of the boat with minimal rocker is one thing. Dead flat is another. When a boat really does have a dead flat spot it becomes confused. There is no well defined turning axis, which there should be and which should correspond to the boat's center of gravity.

How did flat spots happen? Martin LItton went to Keith Steele and asked him to build an 18' foot Grand Canyon Dory. Keith, who was selling hundreds of 15' footers wasn't too excited about working out a new design for a guy who might someday eventually maybe possibly buy as many as a dozen. So Keith chopped his 15' footer in half and added a 4' foot square box dead flat channel in between. And that was the Suzie Two, or was it Suzie Too? Did he ever build another? He didn't build many. So Martin Litton went to Jerry Briggs, who did the same thing. He chopped and channeled a 15' footer instead of scaling it up proportionately.

The Briggs is 48" inches wide and 18' feet long. It sinks way down low into the water and it takes the Incredible Hulk to make it turn. And for all that it's annoyingly side-to-side tippy. I briefly rowed a recreation of the Suzie Two and it wasn't any better. Was much the same in fact. Hard to turn and side-to-side tippy.

So. I don't know what too much beam is but the Cyrus Happy boat is bigger and wider than what I'm planning. And the Cyrus Happy boat rows like a dream compared to a Briggs.

Getting back to the flat spot, if instead of flat you have almost flat you can still build a boat that knows where its center is, that still turns sharply. And still has good buoyancy, with a high ride on the water. More side flare creates too much rocker if you stay with a straight line chine. But if you dish out the chine you can have as much side flare as you want, with any bottom profile you want.

This is a project where 3D hull design software probably would be helpful. But it's too damned expensive. So I'm working it out full size, with cheap plywood panels. I've got two side panels on 4 adjustable ribs now, with stem end and transom end held together with bailing wire. All built on top of a heavy duty cart with six inch caster wheels.

I don't like the shape I've got yet. But I had to take a few weeks off. I'm trying to make a little money with a new self-employment business that isn't boat building related. I'll get back to the big dory soon. I also want to build the smallest possible boat--for two people only. The Buffalo Boat was supposed to be the smallest boat you could squeeze three. I want to do much the same again, next time for two only.



Re: Sandy's Take on WW Dories
November 10, 2015 05:00PM
Well, this is not a concrete science.

You will find that almost all decked boats on the river are Briggs boats. It's not really important way. We have been over this history many time.

I row with a crowd which is in the minority view so that of course makes us all wrong. And having only rowed about 5000 miles in the past ten years as compared to pro guides like Hutchinson and Dimock lets just say their opinions would be viewed more highly then mine which, is okay with me.

Find people who have rowed Briggs boats for many years and you wont' change any of their views on the 48 inch bottom and that's fine also.

So, if you were to go the river with friends with 5 dories and see another 20, you might come across a 1 decked Mckenzie boat. So it would be 24 to 1. You will hear 24 people talk about why the 48 inch bottom is the correct size. The 1 boat with a 56 inch bottom will go un-noticed. So you get convinced that 48 inches with a long flat spot is the way to you. You just committed you first major error.

Who is right in all of this? Each owner is always right if they say they like the hull on their boat but, THAT DOESN'T MAKE IT RIGHT FOR YOU OR ME.

You need to find a way to row different hull shapes because it come down to 1 issue. How does the boat spin. Do you want it to hold a straight line so you can blow down center and take on any wave in front of you in Hermit on the Colorado or do you want a boat which is quick to spin and ferry away from rocks on a low water trip down the Middle Fork of the Salmon on day 1.

So considering that Hutchinson and Dimock are right and some of us are wrong, do you want to be right or wrong or,,,,,,,, is it okay to be wrong and like what you row. So, what do you think you are after?

Size, that's a tough issue. Sandy seems to want to build bigger boats. I don't want to go past 16 foot and I don't want the deck so wide I need to move to 11 foot oars. For me it's got to work with 10 foot oars. I think 16 foot is also kind of a magic number. Over 16 foot and different regulations can come into effect on some rivers.

Just one more comment, wright or wrong, the 48 inch bottom sucks!



Re: Sandy's Take on WW Dories
November 17, 2015 01:36AM
All this is great info. I row a-lot-of-whitewater. But all those miles have been in a Maravia 16' self-bailer I have owned since 1995. I am really used to a slow turning overloaded (down to the d-rings anyone) Suburban stacked to the rafters with tons of stuff. In the fall on our Idaho steelhead rivers I spend my time on the sticks of two different aluminum drift boats. Other than sounding like a perpetual car accident they row OK. I am looking to get my Honkey Dory on the water in the next month, hopefully the Clearwater River in December for some steelies. I want to experience my Honkey on the water and evaluate my decisions like the chine shape and at the same time learn here about the pro and cons of different aspects of hull design for a decked dory. As far as LOA I am thinking between 16' and 17' so whatever that works out to along the gunwale. Above I stated 17-18' meaning around the gunwale. LOA vs. gunwale...hmm, I should have been more clear.

My goals for this dory project are to have a a functional, graceful, tough whitewater dory. I'd like to be able to haul a large fraction of what I stack on my raft, but that may be unrealistic. If a lightly loaded home built drift boat is a Ferrari and my 16' Maravia self-bailer is a 3/4 ton Suburban with a roof rack, I am looking for a something in between like a Dodge Magnum Wagon or a 3/4 Ton extra-cab. I think that paints the picture I am looking at.

As to bottom width, both of the aluminum DBs I use are narrower than the HD at 56". I have no doubt my ww dory will be much wider than 48". Looking back to the Gem and some the preceding cataract boat designs used in the Grand Canyon, they had widths exceeding 48". I can believe the only rational for a 48" bottom was production considerations. The real question rolling around in my head regarding width is how wide is too wide for a ww dory? My 16' raft is freaking wide. I have a couple trips on the Middle Fork Salmon River from Boundary Creek fully loaded with less than 1.68' on the gauge. No big issues. Width at the waterline is about 7'4"....so 88". So in a dory 88" at the oarlocks would not be too much. I can fit through anything on the Middle Fork and Main Salmon at 88". I doubt the Grand Canyon has anything nearly as tight as Day 1 on a low water Middle Fork trip from Boundary Creek. There may be some tighter squeezes on the Rouge but none are coming to mind.

The comment about 11' oars is interesting. I row with 10' Sawyers that are counter balanced. I have 3 sets right now. When rowing 18' Maravia's on the Middle Fork of the Salmon I have used 12' Solid Ash Smokers. Not my ideal set up. It would be nice to stick with counter balanced or Square Top Sawyers. 12' footers would be acceptable.

OK, so no flat spot. My thinking on that topic was related to drafting less water. I think Sandy addressed that: keep rocker, but dish the chine so it is not continuous.
Re: Sandy's Take on WW Dories
November 19, 2015 04:09AM
If you measure along the gunwale and multiply the measurement by .93 you will be close to the LOA.

When loading for a Grand trip, I am actually amazed how much stuff we can actually get below the decks on these boats. Of course they won't haul what an 18 foot raft will but I have never had to cut back. For me there is a point where the boat becomes too big and too heavy. We can get away with a slow moving raft bashing into rocks now and then but it's good to have a dory which you can move when needed. Rocks and hard hulls do not mix. I don't know about 88 inches on top. It will start looking like an air craft carrier or something. While the sides are to low on the HD for really big water, having been on 1 trip with 2 stock decked over HDs we didn't have any trouble. So for someone who wants a smaller boat the HD with taller sides will get you down river just like anything else will.
Re: Sandy's Take on WW Dories
November 11, 2017 05:48PM
Mike, did you ever end up building a white water dory?
Re: Sandy's Take on WW Dories
November 24, 2017 04:51PM
Yes and no. I did all the 3-D modeling I wanted to get a feel for the very hull design questions I posed at the begining of this thread. Along the way another Phorum member gifted me (that is amazing btw! Thank you again Joel) a shell of a HD built in all Plascor. That hull will be completed soon. I am just about to finish the final glass layers on the bottom and flip it.

Having been given the shell I will finish this one and run it and then reevaluate my urge to build a bigger boat! I have a wife and 3 daughters who all row white water and row very well. This current placore Honkey will see plenty of trips even if I build a bigger ww dory. My first HD is an open floorplan. That is the turquoise Honkey Dory that Pat Andersen finished from the hull I built and it rows like a dream and is tough as hell.

It funny how all these threads and friendships come together. Pat later build an all wood traditional framed McKenzie with a clear finish. I have yet to row that one to compare to my Honkey but soon will.

-MikeInBoise
Re: Sandy's Take on WW Dories
November 24, 2017 05:20PM
Cool, I live up in Donnelly so let you know if you're ever putting her on the water around here...I'd love to see her on the river! Where do you normally boat?
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