Jerry and Andrea at the Island Falls Canoe have an original 15 foot long Old Town form that was used for the Fifty Pound, Lightweight, Featherweight, and Trapper models. I sent them a message about this thread and asked if they could measure the rocker for us. They have very kindly responded as follows.
"Andrea has attached a few photos of our 15' Trapper form. In the long view you can see that the rocker is all located in the ends.
The run along the bottom is perfectly straight until you get to the start of the stem slots. In the closer picture with the level you can see the rapid drop off - or rise if the form was right side up.
By measurement it goes like this. The piece of tape is at the end of the stem slot.
At the second rib from the end the measurement is 1/8"
Rib 4 = 1/2"
Rib 6 = 1 1/8"
Rib 7 = 1 3/4"
Rib 8 = 2 1/2" (often a cant rib)
At this point the curved part of the stem becomes the major factor.
So yes, the rocker is built into the form. But only at the stems.
Island Falls Canoe
220 S. Stagecoach Rd.
Atkinson, ME 04426
View attachment 50203 View attachment 50204 View attachment 50205 View attachment 50206 View attachment 50207 View attachment 50208