Just wondering If i can up scale a set of plans i like ?
I just want a slightly larger version of a boat i like and was thinking I could simply enlarge the forms by about 3 % on a copy machine .
Will this lead to a bigger boat or a whole set of problems i don't see .
thanks in advance
teddy

You don't mention whether you need/want more width/depth, or just a larger boat with more storage capacity and ability to support a heavier paddler than the original design.

It's generally accepted that it's easier to keep to the original intent of the designer by increasing the length of the boat (by increasing form spacing) if you want a larger boat. As an example, the plans I have from Bjorn Thomasson provide capacity data for different form spacing. For Frej, data is provided for form spacings between 37cm and 41 cm for boat lengths from 481cm to 533cm and design displacements from 129 to 142kg.

However, I agree with Bill that a 3% increase shouldn't cause a big problem. This is not to say that most paddlers cannot notice an increase in width of 3/4" or so - it does make a difference.

What design are you thinking of altering?