If you're doing the very traditional JP block (I know there are some faux patterns out there):
The middle seams of each block are NOT supposed to match up with the middle seams of the adjoining blocks.
The only thing "matching up" is the intersection of the four patches within a block.
That's it.
Is that the problem ...you're trying to line them up?
You should join the blocks like you would diamonds....offset by 1/4" (little dog ears) so that after you sew the two blocks together, when you turn the block back, it now creates a straight edge along the top and bottom of the two blocks.
When joining, you treat the four patch as a whole block...don't worry about those middle seams.
They will offset a little - which they're supposed to - which creates that dynamic pattern.
And you continue on from there.
I can't find my JP wallhanging. And the workpapers from when I taught the class are AWOL (again) as well.
Hope this makes sense to you.
It's one of my favorite patterns.
eta: Check out close-ups of Twister blocks...same concept, except the JP block is not square.
Last edited by MTS; 11-10-2012 at 12:24 PM.