Clicky

Stitch and Glue No Plans

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
Stitch and glue without plans
For quite some time I've wanted to duplicate a popular fiberglass pirogue in cedar strip or 3mm okume because the fiberglass is just too heavy. If this sounds familiar I’ve tried before and went back to building from plans.
I have tried tracing the sides of the water mocassin several times to no avail. If Bee keeper can copy sides on tar paper I can too!
This time after reading every post I could find, I decided to “eyeball’ it.Jdupree,seedtick, and several others post have been helpful.
After reading and looking at different plans I “eyeballed” two sides first out of ramboard then cedar strips (didn’t have any Luan big enough and had lots of short cedar strip The ramboard mock up looked pretty good, I thought the sides may work. But when they were built in stiffer cedar, they had too much rocker when I tried for the 35degree flare.I know that’s a lot of flare but if Bee keeper can do it….. anyway here are pictures and questions.








This pic is with a left over rib from an uncle john type build the flare is about 20 degrees. The rocker is a little more than I want, but acceptable. Of course when I put a 35 degree form in place the rocker goes out of site about 4 to 6 “. The other pictures show more information about the panels. These panels are a little over 7” tall, I could take them down to 6” to be like the Water Moccasin. ⁷
1. How would I change these panels to make my next attempt successful?

2.My guess is much more arc in the chine side of the rainbow. Would I also need to put more arc in the sheer side?

I’m considering increasing the arc on the chine by an inch in the middle of the side. Not sure how to loft that curve. The side panels are about 7” high I could take an inch off in the middle.

3. How much would the angle of the stern and bow affect the flare and rocker.

4.I am open to any and all suggestions to make the next pair of sides and or modify these.My objective is a short fat pirogue with about 35 degrees of flare. Doesn’t bother me to start over.

Thanks,
Andy
 

beekeeper

Well-Known Member
Mar 4, 2009
1,645
35
I don't know stitch and glue but I will kick off the brain storming. Take the trial panels you show in the "chine curve" picture and cut another inch off the chine side curve. Spread them to the 35 de. and note the changes in the rocker. Ignore the sheer edge for now you can add to it later if it is not tall enough after cutting the arc. If the rocker is not enough cut a little more and try again If it suits you measure the boat's panel from chine to sheer and mark and shape the pattern's panel the same. I would guess I said guess, the sheer and chine lines are parallel.
 

beekeeper

Well-Known Member
Mar 4, 2009
1,645
35
Try attaching the panels to the form secure enough (screws) so it keeps the angle you want. Block each end at the stems on the table. Boat should be touching at the widest point of the bottom ( where your form is). Wrap a batten from one end to the other. Similar to an outside chine log. Measure the height of each end to the table. Example 6" at each end. Raise the batten to 4" from the table at the form and the difference = 2" and should be the rocker at each end.
Mark and cut pattern panel to this arc and and the mock boat should have 2" of rocker.
Rocker is the difference in height between mid ship (asymmetrical) and each end, but you have to bend the panels to your desired flare before measuring because as the angle of the sides increase so does the rocker.
You can also move the sides in or out to adjust the rocker but this won't work for you when copping the Moccasin. Moving the side angle also effects the water beam, capacity, depth of the boat and stability.
 
Last edited:

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
Try attaching the panels to the form secure enough (screws) so it keeps the angle you want. Bock each end at the stems on the table. Boat should be touching at the widest point of the bottom ( where your form is). Wrap a batten from one end to the other. Similar to an outside chine log. Measure the height of each end to the table. Example 6" at each end. Raise the batten to 4" from the table at the form and the difference = 2" and should be the rocker at each end.
Mark and cut pattern panel to this arc and and the mock boat should have 2" of rocker.
Rocker is the difference in height between mid ship (asymmetrical) and each end, but you have to bend the panels to your desired flare before measuring because as the angle of the sides increase so does the rocker.
You can also move the sides in or out to adjust the rocker but this won't work for you when copping the Moccasin. Moving the side angle also effects the water beam, capacity, depth of the boat and stability.
 

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
Thanks for rhe replies, I appreciate you taking the time. I have been to Water Moccasin a few times she no longer has the 10' mold. BUT the last time I was there I left with a brandnew 11 footer!
I marked the panel to increase the arc, but think I like your secnd idea if I understand it. I'm headed out side to see if I comprehend what your saying. Ive got to rip something for a baten first, I used every left over strip I had. Be back with you tomorrow.
Thanks
Andy
 

jdupre'

Well-Known Member
Sep 9, 2007
2,167
19
South Louisiana
Andy, what helped me more than anything is a quarter scale model. Divide every tentative measurement by four and cut out the sides. Put in a suitable center form, bring the ends in a tape them in place. You can tune in the model SO much faster than trying to do it full size. You'll see the effect of more or less chine curve immediately. Soon, you'll get a feel for what you need. And, doing an experimental project demands a certain amount of feel that can't be captured in pure numbers. In the end, if it looks right, it is right.
 

beekeeper

Well-Known Member
Mar 4, 2009
1,645
35
I have questions.
1. What are the dimensions of the form? Width at the sheer, and at the bottom? How tall (deep)?
2. Length of floor and overall length of boat?
3.How much rocker do you need?

Building "by hand and eye" is harder than building by plans or putting together a kit. Doing it to specific dimensions is even harder. The arc and flare of sides relationship is not simple. That is why many builds have near vertical sides and/or lots of rocker.
You are close to getting what you want. Cutting some more off the bottom of the panel will get you closer. The worst that could happen is you cut too much and the rocker goes away. Then you know not to cut that much the next time.
Just noticed in your picture your arc is cut about 2". A guess, a guess I say you might need 3" to 4". Just sneak up on that 1/2" or so at one time, because I don't have a formula.
 

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
Jack you are right. I think I'm finally on the right path. In the last two days I finally have interacted with how stem angles, width, flare, and shape of the sides are interrelated. Bee Keeper and jdupre' opened my eyes! I guess you could say I saw the light-- now to study it and learn to live it. I amazed how just a simple suggestion by jdupre' to plan large and divide by 4 to build your model, solved my understanding of how to use a model. I've built models 2x, but couldn't enlarge them successfully. Thanks gentlemen I no doubt will be back for more:)
Good Fish'n
Andy
 

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
I have questions.
1. What are the dimensions of the form? Width at the sheer, and at the bottom? How tall (deep)?
2. Length of floor and overall length of boat?
3.How much rocker do you need?

Building "by hand and eye" is harder than building by plans or putting together a kit. Doing it to specific dimensions is even harder. The arc and flare of sides relationship is not simple. That is why many builds have near vertical sides and/or lots of rocker.
You are close to getting what you want. Cutting some more off the bottom of the panel will get you closer. The worst that could happen is you cut too much and the rocker goes away. Then you know not to cut that much the next time.
Just noticed in your picture your arc is cut about 2". A guess, a guess I say you might need 3" to 4". Just sneak up on that 1/2" or so at one time, because I don't have a formula.
Thanks Ithink we were typing at the same time, see below. Ihope send some progress pics in a day or two.
 

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
There is rejoicing at the Texas Tin Shed this morning. I have sides of a pirogue 9ft long 30,"bottom, 35 flare, 2 ""rocker in bow 1" rocker in stern. Bee keeper and jdupre' are some smart fellas, and after 2 years of splain'n I think I under stand. I planned on 9'4" but next time! Bee your idea about a baten and subtracting the rocker was right on. makes sense now. I have a good start, but next time i will plan a full scale, devive by 4 and make a model.
 

jdupre'

Well-Known Member
Sep 9, 2007
2,167
19
South Louisiana
Good news! Now you have a certain feel about what effects what. That feel can be carried over to other even unrelated designs. Some guys are different on this site, but I reckon I could build a decent pirogue with no tape measure. Millions of boats have been built without one.
 

oldbuffpilot

Well-Known Member
May 13, 2014
398
12
77
Central Kansas and Central Texas
How much did arc you have to cut off the chine to get the rocker you wanted?
About 4". I'll measure and makae a post later. you were pretty much right. Of course I complicated it by going assymetrical. The by eye thing has had me making changes as I go, I
ve settled on the final hull shape and will remeasure and post.
I'm working on tumble home and
disadvantaged by not having luan to play with! With my brides cancer treatment I just cant risk going to Home Depot. I'm working with slow progress. I remember you once posted pics of cutting tumble home?
Later,
Andy
 

beekeeper

Well-Known Member
Mar 4, 2009
1,645
35
"Pretty much right" is about all I can hope for. If you are copying a design the "by eye" kind of goes out the window. If you just want to build something similar then "bye eye" will get you there. I have made the tumble homes with plywood or strips.
Place oversize panel in place and mark the desired shape using a batten for a fair line. Mark and trim off.
............
IMG_2473.JPG

IMG_2471.JPG
IMG_2474.JPG
IMG_2476.JPG
...................................................................................................................................................
 

beekeeper

Well-Known Member
Mar 4, 2009
1,645
35
Thumblehome with strips. Shape the inside strip to your desired shape and size. Fill in the remainder strips and trim flush. I found bead and cove keep the strips flush with each other and reduces sanding. If you don't mind the look of straight strips you can make an oversize panel on the work table and treat it as a plywood panel. Probably would not need the bead and cove.
IMG_3720.JPG

IMG_3721.JPG

IMG_3730.JPG