Make sure your tension is set right. Use blue or gray thread. If the lilac pleases you more then use it.

Have you tried deb tuckers Lemonyne star ruler instead of paper piecing. I have heard her rulers rock and its for that style block. I would also try gray thread since using a darker color. I like your block, and I don't think the recipient would really notice the thread the way you do, we tend to be more critical of our own work

Sorry - I noticed the light colored stitches. (If you had not mentioned it, I would not have, either.)

As you discivered, the dull lilac worked like a gray. So does a medium smokey blue or mediin smokey/ dull/drab green .

Nice job on the seam matching.

Just wanted to say your block is gorgeous! That's what I noticed, not the stitches.

I have one other suggestion, use size 60 thread for your paper piecing as it is thinner than 50 or 40. It will bury itself in the seams that have the shorter stitch easier. I would definitely choose a gray thread so whatever does show will be less obvious. Have fun paper piecing.

I bought these pens more than a decade ago and they still work!! I use the fine points the most. I used them to camouflage stitching and also flaws in fabrics. What a life saver !! I use mostly gray in my piecing unless there is white or ecru involved.

That was what I was thinking. And as Jan said, over-thinking. Could you see it from the back of a running horse??

I have been paper piecing for a long time , and could not figure out why the same thing was happening... Then it hit me, after re-sewing on the original stitching line after the papers had been taken out..... Its the paper... the stitching is laying on the paper and not getting the tension on the fabric... so once the paper is removed there is loose tension. How to fix this problem..... a few things to try, increase the tension, or once you have trimmed those outer units remove the paper then join the units, or use thinner paper ( think cheap newsprint) so the stitches can get better tension on the fabric. I also found that I was ever so slightly stretching my thread as I was pressing my units. When I leave the paper in and press ( and I love my steam) the thread when I use heat and steam stretched to accomidate the thickness of the paper, so once all the papers are removed and the thickness on the paper is gone... the stitched thread stretched and is not the correct tension.
I figured some of this out when I used "real" paper piecing paper , its thinner compared to the cheap copy paper I was using.
I feel your issue on this matter, you finally get perfect points only to get your thread showing... frustrating.

Your block looks great, love the colors. I use a 1.5 stitch for PP. Glad the lilac thread is working for you. The three basic threads I use for piecing are ecru, grey and black and that covers 99% of my piecing.

I might switch to a grey thread for stitching, and if the stitches still show, I wouldn't worry because it may never show when quilted, and if it does, use a Pigma pen to cover up the wayward stitches. You are doing a great job piecing this block, and I love blue and white.