UJ Pirogue: Changing stem angles, effects on rocker?

[lahonda]

Hi everyone,

I have been lurking around this forum for a while now and this is my first post.
I have the UJ Pirogue kit and would like to change the angle of both the bow and stern angles and I'm concerned how this will affect the rocker.
I would like to change the 45 degree angles to: bow 75 degrees and stern minus 15 degrees (the stem would be slanting 15 degrees toward the bow).
The reason I wish to do this is I've found a profile of an old canoe that has these angles and I really like it. The pirogue (if it can still be called that after the stem changes) will be both paddled/sailed with short crowned decks at each end (a flat bottomed sailing canoe?).

Thanks in advance,
La Honda

 

[seedtick]

i don't know but would suggest that you build a half scale model - sides only, no bottom - using the cheapest plywood you can find and see if you like it

 

[oldsparkey]

That's a rather radical change , best to check with Uncle John.......

Chuck.

 

[Paddlin'Gator]

If the sides are made from straight pieces (like 1x12s) the rocker is determined by the flair of the sides. The greater the flair the greater the rocker. In an extreme example, if the sides had no flair (were vertical) the bottom would be straight (no rocker). Unless you put a twist into the side panels, the stem and stern angles are predetermined by the flair of the sides. Of course, you can alter that relationship between flair and rocker by having the edges of the side panels curved rather than straight.

What you want to do sounds as if it would be better suited to strip construction than typical pirogue construction using planks or straight rippings of plywood.

Joe

 

[mosportsmen]

I had the same debates in my head before I built my last pirogue. Get some poster board and make a model and play with the dimensions and angles. All you have to make is the sides to get the ideas and see the results you are trying to wrap your head around. It is the side flare that mostly determines the rocker . I cut the 45 angle in half to 22.5 and it worked for me. I wanted to eek out a little more surface area on the bottom of the boat to increase weight carrying capacity. I don't know if I accomplished that goal but it satisfied my spirit of individuality.

 

[beekeeper]

........ I wanted to eek out a little more surface area on the bottom of the boat to increase weight carrying capacity. I don't know if I accomplished that goal but it satisfied my spirit of individuality.

Nice boat. Looking at your pictures it appears you added the transom after you built the boat and then cut the stern stem piece off. If overall length is not an issue, another tip "to eek out a little more surface area on the bottom..." (Keith and seedtick gave me) is to put the transom in place of the rear stem when you build. No wasted wood, less build time, and you gain foot print ( if that is your goal).

beekeeper

 

[lahonda]

Thank you all for your great advice. I will be building a model and see if the changes to the stem angles work the way I hope they will.

Thanks again,
lahonda