Big Canoe-Big Project-Questions

[battle]

I am planning on building a 22'-24' wood strip canoe for use on the lower mississippi river. I have searched for plans for a canoe this size and found none that meet my vision. I plan to use my boat specifically for downriver trips on a river that is literally a mile wide. No rapids or "real" whitewater, but there are often big rolling barge wakes, wind driven waves, and turbulent water around rock dikes. I have been paddling this water for some time, mainly in sea kayaks. Paddling is relatively new to locals on the lower Mississippi, so there are no crafts designed for this water, with the exception of one guide who has built a 27' and two 30' voyager style canoes. He has offered the use of his plans, but his canoes typically take 6-8 people to power. I would rarely be able to put that kind of crew together for a weekend trip, so I want something a little smaller. I want a canoe that would handle up to 5 adults, but could still be handled by two adults and two kids and gear for a weekend. I am not looking for a speed boat, obviously, but I need to be able to maneuver around large obstacles at a reasonable pace.

Do any of you folks out there know of a suitable design? I have looked into the idea of scaling up existing plans, but often get an unmanageble beam(4'+).
I plan on using Ted Moores' "Canocraft" as my guide through the build. The Hiawatha and Redbird are the closest to the style that I am looking for.

Right now, my most viable option for plans is:

Outback 200™ by Valley Woodworking

Length Overall 20 feet

Beam 42 inches

Rocker 1-7/8 inches

Depth (at center) 15 inches

Stem Height 22.5 inches

6-inch Freeboard Capacity 1300 pounds

Completed Weight (with trim) 90 - 95 pounds

Station Spacing 12-3/4 inches on center


http://www.valleywoodworking.biz/outback.htm[/URL]

My thoughts:

1) I could get the desired length by increasing my station spacing by 1" to 1 1/2" Is this a bad idea?

2) Is 42" too wide. I like the idea of extra width for stability, but would this thing be unbearable to paddle?

Am I making a mistake by "monkeying with the plans? Will increasing the station spacing destroy the "fairness" of the hull?

Any thoughts, suggestions, or even better, plan recomendations would be greatly appreciated.....

 

[Rollin Thurlow]

a 42" beam for what your looking for may be non too small. 5 adults would be around 1000 lbs. I would estimate that the Outback 200 would be a bit small for the use that you discribed. Its not uncommon for a general recreational canoe to have a 15" depth so for your use I would think something approching a 18" depth, 45" beam would be more the size that isneed, but at that size it is making it more difficult for just two adults to handle.
Most canoe plans can be expanded a bit before serious problems come up but its a guessing game on how much is too much. A lot depends upon your building experience and skill and how much you want to fool around with the set up for the stations. In order to get the strips to lay smooth on the expanded plans you may have to do a bit of shiming and reshaping of the stations which can take a bit of time an a lot of stareing at the form shapes!
It can be fun if you enjoy that type of work. If you don't enjoy that part of the buildng process and just want to get the canoe off the form then the canoe might end up a bit lumpy but still perfectly servicable.

 

[battle]

Thanks for the input Rollin. I have ordered the plans for the outback 200, so it looks like that will be the basis for my canoe. When I get my forms cut I am planning on setting up different spacings and using "test" strips to see what is feasible. I do not like the idea of shimming the forms! Max length looks to be more like 22.5. 24' would probably be stretching WAY too far. I am planning on using a local machine shop to cut my forms, so I may be able to change the depth when they have the plans entered in their computer. I'm not sure what the capabilities of their software are, so it will be interesting to see what is possible. Things would be much simpler if I could find plans that meet my specific needs!

 

[Mark Adams]

Get a war canoe! They are 25', be great for big waters.

 

[Todd Bradshaw]

You can usually figure your length and approximate stations on paper by drawing a few curves in scale and then mount the stem forms and center station on your strongback. Place your other forms where indicated by the drawing and then use a handful of stapled-on temporary strips to test for fairness as you adjust the forms as needed. We used to use a hot glue gun to hold the forms in position while making adjustments and then bolt them down once everything seemed OK. It's not a bad idea to make your forms a few inches deeper by extending them above the sheer line a bit. It will allow adding depth, if desired, and make sure that you can eventually fair-in a nice sheer line curve without running out of topsides anywhere.

I wouldn't reduce the beam. Four or five people sitting on seats for unloaded day trips with their weight concentrated pretty high above the floor can benefit from some pretty serious beam. I would ask the designer whether they have actually built and tried one for more than just a test paddle. Wide strippers sometimes tend to exhibit a lot of bottom bounce (which isn't good for them and is a sign that they need more beef on their bottoms). If they have a proven construction schedule (strip thickness and fiberglass weights) that has worked well on the design, I'd pretty well stick with it and not try to get cute with changing the layup.

Two people paddling a 22'-24' "group" canoe is seldom much fun as it feels heavy and slow to accelerate, but it can be done if the wind isn't too bad. If that will be a frequent scenario though, I'd be very tempted to put a small wishbone transom on the stern for some auxilliary power. I've paddled my 22-footer with just one other person and it just felt like a big, heavy canoe - slow to get moving, but not too bad once up to speed. I wouldn't call it nimble, but the handling was reasonable.

 

[battle]

Great info Todd! Thanks for the reply. From the info I have gathered thus far, I do NOT plan on changing the shape of the stations (beam, depth, etc.) but I am going to try to stretch the overall length by increasing station spacing. Here is some info I got from our local builder, John Ruskey:

(the boats referred to are ladybug-27',Junebug-30',and Junebug II-30'

"Ladybug" Model

max beam = 54"
waterline beam 50"
center depth = 17, 18 and 19 1/2

I purposely made JB I deeper for more rough water conditions. JB II = 18". Ladybug's 17" has served her well -- we very, very rarely have taken in any water (one of the notable exceptions was during the rescue operation after your capsize!).

I had 13 people + myself in the JBII over the weekend, surely its max. load, which resulted in 12" of freeboard, and still we didn't take in any water, not even through some tugboat waves.

What problems should I expect to encounter from stretching a 20' plan to 23'-24'?

....the trickiest thing is with the increased spacing between the stations -- even when done with mathematic precision there is certain to be some morphing from the expansion -- as result you will have to very, very carefully inspect the finished form for continuity, and make any necessary adjustments before starting the stripping -- plan on spending a week just on that, getting the form lines right -- spend lots of time with it, in the morning, evening, whenever you get a moment to really concentrate and "See" the lines (and not after a couple of beers!)

Also, everything will have to be a little bigger, of course -- you'll need significantly more glass & epoxy/resin

How long will my strips be? Is 25' redwood or cedar available NO, not that I know of . Max length I've ever seen is 20 foot. You'll have to splice ends (butt joint is fine for this, but you could get fancy & do warf joints).

and at what cost(estimated)?

probably around $2,000 for all your woods combined (if you go the cedar/redwood/ash route. Half that if you go with cypress/ash.

-John/QUOTE]


Also- Todd what plans/designer did you use for your 22' canoe? I would love to get more info about it. If I could find a set of plans that did not have to be lengthened, it would take a lot of the guesswork out of my project. I realize that when you veer from the original design, it is possible to end up with very different results! It would be tragic to spend the effort and money to build a stripper, and not be happy with the end result!

 

[Todd Bradshaw]

I modified a plan from Adney and Chapelle's book "The Bark & Skin Boats of North America". I reduced a bigger boat a bit and then added about 6" of beam to give it better stability when unloaded (fur trade canoes had pretty narrow bottoms because the cargo worked as ballast). We had to work within some limitations. The length was limited by the diagonal corner-to-corner measurement of the garage we were building in and I chose a profile with shorter stems than most of the boats in that size range usually had. This was so that it could be carried on a van without the stems totally blocking the windshield.

 

[Canoeal]

Take the plans for the 18' Micmac, From David Hazen's book, draw an extra center form and space it the same as the others. That should give a 20' x
36"+ by 13" canoe to do what you want. If you want it a little longer than that, space the forms in the middle 2 sections a little farther apart.

 

[Dan Lindberg]

Just to keep things confusing, I'll throw out a different method.

When I was building my 2ed canoe, I stretched it from 17.5 to 18.5, and prior to doing so, had a series of exchanges with the designer.

Anyway, his comment was in order to keep the same shape, all the dimensions should be increased by the same %, and if possible, try not to go over 5%. To do this, I enlarged the sheets by running them through a copy machine, set at 5% enlarge. To increase the length, his instruction was to increase the station spacing by an equal amount at all stations, in my case, to get the 1 ft increase, it was about 11/16".

All of this resulted in a shape that was fair and true to the original, except 5 % larger.

Dan

 

[battle]

well.....
Here's what I did to increase the length of the Outback 200 from 20' to 23.5':

I increased the station spacing from 12.5 to 14.25(can't recall exactly) and used two center stations. Had to use the two center stations because I was afraid to stretch the station spacing too far past 14". I am pleased with the shape of the hull, but it did flatten out slightly on the sides where I added the center station. The flat sides are completely unnoticeable when the canoe is turned upright(attaching the gunwales restored a fair curve to the sheer), and I am very pleased with the shape/fairness of the hull. because the profile of the bottom is essentially the same for stations 0,1, and 2 on the Outback 200, the additional 0 station did not affect the bottom shape at all. I must warn, for the perfectionest or professional builder, the slightly flattened sides may be unnacceptable. One thing I liked about adding the center station is that I added a significant amount of volume in the widest part of the canoe, which I hope translates to even greater weight capacity. I hope to get out on the water next month, to actually test my modified boat. I have built the canoe with four seats- I am hoping to carry four or five adults plus gear for weekend trips. All I have left in the build is varnish and caning the seats!


random info:
strip material- louisiana bald cypress
trim and outer stem- black cherry
overall length-23.5
beam: 42"
weight: 128# (before varnish)

the capacity with 6" freeboard at 20' design is 1200#- I am hoping my modifications will increase this by 200-300 #. We'll see.

glassing: outside-3 layers 6 oz. on bottom, 2 layers on sides. inside-2 layers 6oz. on bottom, 1 layer on sides. maybe overkill, but i'd rather be a little heavy than have too much flex...

btw- the addition of a center station was recommended by the designer

That's Bell my red and white border collie, posing in the canoe!



View attachment 10066

 

[Canoeal]

If you are expecting the capacity to be in around 1500 lb, I by I think you under guessed. By my calcultions you increased the spacing by 14 percent. that would increase the voulmue and related capacity by 14% to 1368. you added about 3 cu ft of vome with a extra form, adding about 200 lbs of capacity. That puts you at 1568 lbs. so that's OK.
But, when I looked at the canoe on Valley's site. they claim the outback 200 to have 1300 lbs of capacity. redoing all the math, and using 1300 as a base yours should be up around 1668 lbs., so you should be more than OK.
By the way it looks great!

 

[battle]

Launch!

Thought I'd post up some photos of my finished 24' "big" canoe:

Thanks for the input, guys! Now its off to the 29th annual Memphis in May canoe race. She's pretty fast with a six man crew!

 

[Todd Bradshaw]

Looks great! The last photo reminds me of the time I drove across town with my 22' fur trade canoe on top of my '65 Chevelle - only with the high, voyageur-style stems on mine it made it darned difficult to see.

 

[Dan Lindberg]

I agree, you made a very nice canoe.
It looks great being used on the water.

Dan

 

[battle]

if anyone was wondering why I wanted a big canoe....

We share our river with some pretty big boats!

 

[Todd Bradshaw]

Just remember that as a paddle-craft, you have the right of way. Also remember that you're probably the only one who gives a hoot that you have the right of way.