I have a bunch of 5inch (4.5 finished) nine patch blocks. I would like to make into a baby quilt using nine patch ,1/4 square triangles then another nine patch. What size should my squares be to start to make the 1/4 triangles. Clear as mud I know. LOL.
True4uca

Using the Quilt in a Day triangle square up ruler instructions.
Cut 2 sqs 6 inchs, draw line corner to corner and sew 1/4 inch from each side of line. Cut on both diagionals then press toward dark. Match the pieces with opposite fabrics next to each other. Sew the pairs togather.
Set seams and press open. Square up to 5 inchs. Makes two blocks.
This ruler is a must have for both HST and quarter triangle sqs.

Knew I was wrong,my careful math worked out to be 6.5 inches. Yours sounds better.
Thank you
True4uca