I really hate to admit that I'm so awful with math that I have to ask for help for measurements....BUT I NEED HELP!

My pattern will be the disappearing nine patch... and I need my blocks to be unfinished 12 1/2.

What size would I need to cut my patches?
Should I cut them 5', and then square up/cut my block to size?

Thanks for your help!

Each block in the 9 patch is cut 4 1/2" :D:D:D

The problem is to get a D9P to come out exactly 12 1/2 you have to start with a really odd measurement that's nearly impossible to cut. Unless it's for a swap of some kind just let the blocks be the size they want to be.

Yip!

Which makes a 12 1/2 inch 9 patch. You reduce it by another half an inch when you make it a disappearing 9 patch. So that makes it a 12 inch unfinshed block and only and 11 1/2 inch finished block. A half an inch does not divide well by 3.

Yep, sorry, forgot to mention the blocks were for a swap..

I guess I should go large and cut down.

Thanks everyone!

Working on one right now. Each square is 4 1/2 inches

If you go large and cut down, be careful that you cut the same amounts from each side of your blocks or it will look like it is a little "off". Good luck with it!

If you wanted it to end up "unfinished" at approximately 12.5 inches, you might try cutting the pieces like in the attached drawing.

Cut four 4.5 inch squares
Cut four 4.5 x 6 inch rectangles
Cut one 5 inch square

A bit of an adaptation, but I think it would work.

I'm with Scissor Queen. Sometimes things want to be what they want to be. I won't stand in the way. LOL