At first the idea seemed perfect: do a 3d model, UV map it, print the UV map and sew it into, well… A plushie. blushes
The model is done (easy enough), I’ve done the seam-lines for the UV Map, they are placed where you usually see the seams on plushies, unwrapped and then came the nasty surprize:
Blender re-sizes the areas (islands, I guess that’s the technical term for them), so they don’t keep the proportion in relation to each other. For example: the arms are bigger than they should be and the shoulder seam on the arm won’t match the size of the shoulder seam at the body.
I guess it was programmed like that to optimize the UV map area, so my question is: Is there a way to turn this off so the parts will have the size they should in relation to one another?
Select the uv islands and use UV / Average Islands Scale menu
This assumes you haven’t placed the seams poorly and use cleared the objects scale (Ctrl+A) before you unwrapped
While I do have a pretty good spatial vision/sense, I have no idea if the seams are the ideal, but the UV test grid looked OK when applied to the 3D model, the only distortions were those you would see on on real patterned cloth covering a curved surface, so I’ll take it as a sign that they are good.
I did what you said and after a lot of rotating the islands around on Gimp I verified that the sizes are mostly right, only the outer edges of the islands are a bit off, but not by more than half a centimeter (wild guess). I’ll deal with that with a pencil and a ruler on the printed map. All in all, Blender already did the bulk of the work, which usually takes me a while and lots of trial and error, plus making the 3D model was pretty fun.