ninab

Hiya!
I just finished the Quiltworx Dresden blade 18" square. My first paper piecing project (Craftsy unlimited).
The first two blades joind perfectly. Every blade afterwards was a consistent 1/16th of an inch off.
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I checked my seam allowances - I sewed perfectly on the line, and had a perfect 1/4" seam allowance. I measured Multiple times during the process. I used my purple thang and a ruler to check 1/4" from stitching to the edge of the fabric. Disgruntled with the lack of perfection, I decided I'd not do the other three blocks (more fabric for my stash <sigh>) and moved on to the Pat Sloan pineapple quilt for my daughter. Instead of making a bazillion 2.5" squared, I joined multiple 2.5" fabric strips to give the pineapples a scrappy look. (DD has requested a gray background)
Each section of the 4 2.5" squares sewn together are exactly 1/4 inch shy (totaling 1/16th off on each seam!). After calculating the 1/16" per seam loss across the entire width/length of the quilt, this means, upon completion, I'll need to add a 4.25" border to have the quilt come out to the expected size.

Has anyone experienced something like this before? I mean, at least I'm consistent... I've taken great care w/my cuts, I measured the wazoo out of all my seam allowances on the pineapple stuff - and I'm still facing that 1/16th of an inch issue.

Your wisdom is Much appreciated!

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