Technically, jelly rolls should be 2-1/2" wide. I bought two colorways of the same designer (sorry, can't remember which) (one brownish-yellow and one bluish-pink), sewed strips together and cut them into half-square triangles. Then I lined them up so I have bands of light fading into dark, with blues & browns side by side.

As a beginner, I would have to teach myself all over again how to correctly cut the triangles so they were the same size. But once that was done (took only two mistakes per cutting time), I used the ruler the exact same way on the brown and blue elements. You would think all the triangles would be the same, yes? Well, it didn't work out that way!

all the blue elements are wider than the browns by as much as 1/4". I finally figured out that the brown pack is narrower than the blue pack, and combined into three strips per triangle, it makes for a big difference.

at this point, your advice will be on how to deal with this in the future; I am now in the sewing-into-squares phase, and will even up the sizes after they are all done. This will be a wonky quilt, as the center strips of the brown ones won't match the center strips of the blue ones.

Thanks in advance for your insight.
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