Mathopenref.com is my go to for diagonals. School down and when you put the 3.5 into the side, it comes up with just under 5” on the diagonal unfinished. Everyone’s suggestions are great.

I should have tried it before posting��. Site is http://www.mathopenref.com/squarediagonals/html. For some reason I can’t copy to here on my IPad.

Sorry it is not working

Make your four patch borders and measure them before you try and figure out the plain (coping) border. after you have the four borders (2 sides, top and bottom) measure them and you will have some math to figure the coping border. there are tutorials on line http://quiltyfolk.blogspot.com/2014/...-when-you.html or come back and pose the question and someone will do the math. It's a beautiful quilt.

Ok, I finally have it figured out. Go to www.mathopenref.com. Scrool to bottom and click on Index by Number. Click on D at top of page. Go down and click on Diagonal of A Square. I like that you can calculate dimensions if you only have side or diagonal measurement.

Thank you! I took a quick look at the link....although it made me break out in a sweat, it has some really cool applications! I did not receive a math gene, so this will be helpful! Thanks!

Peggy, your link is helpful as well. I am a visual learner, and her diagrams are helpful. Thank you!

Progress! Not thrilled with the corners, but they will blend in more as the additional borders are added...thank you all for your help!

That is looking beautiful!!

Okay NOW I see what you're doing. Huh. It never occurred to me to do my on-point squares as 4-patches! :thumbup:

This has been so much easier to design the pieced borders before the coping borders....you all are so smart! :)
But I can’t get past those corners on the on-point borders....they look like bandaids to me!