Here is a link to a tutorial that may help:
https://www.thesprucecrafts.com/quar...quilts-2821362

The standard is to sew 3 strips 2.5" wide together, iron, then measure across all of them. This gives the most accurate indication of whether your seam allowance is too big, too small, or just right.

Well, here's the final verdict. After looking at images on GOOGLE for "scant 1/4 inch" - I see my issue. If I were to sew at a scant quarter, I'd be spot on... Moving forward w/the pineapple quilt, not changing anything. My next quilt, I will sew a few test pieces and measure, using the scant quarter. Quilting is such a learning adventure, no? LOL

Fdid you copy the paper pieces or purchase them there is distortion when copying

my foot was wiggly too... it happens with age. I replaced it and VOILA!

I've come to the realization that I need a seam guide in place if all my seams are to be accurate. I can sew accurately using the mark on my machine when I'm bright eyed and bushy tailed but after a while I get tired and my seam wanders a bit. That being said, as long as all my seams are consistent, even if they're a bit off the 1/4 mark, I don't worry. I've never made a quilt to be a certain size...it is what it is.

I"ve been using a seam guide, too. It really does help. I'm the same about starting out and being really good but as the day wears on, I get less attentive and my seam allowance does vary. The seam guide keeps it accurate.

Did you possibly copy your pattern on different machines? Sometimes the copier can distort a pattern.

I can have the perfect scant 1/4 " allowance and still be a little off the measurement. I have to make a sample unit and measure that not my seam. Funny how each unit has a different needle placement. Never figured that out. I'm just glad my seams match.

It could be the printed pattern. I've heard that if you take and print a copy (say from a website) and then you use that copy to print another copy, the second copy will not be "exactly" the same size. Something about the fact that the printer reduces the second copy just a hair. So that being said, in order for all the copies to be exactly the same you would need to print all the copies from the main website that you originally printed the first one and not make copies of copies. I hope this makes sense. By the way, your block is beautiful!

I share your pain, but I have decided that if I always use the same machine, my blocks should all be consistent. I am not a fanatic about my blocks, and I am not denigrating anyone here; I am just plugging away at my projects and using what I produce. Happy Quilting everyone!