My stain glass
 

Here's two I've done...Brick wall is a Poppers pattern...the other from one of my books which is PP'd.
There are many pp'd stain glass books out there to make it easy...

this is mine, I used 1" sashing that finished at 1/2". By doing that, I was able to cut large sqaures and cut them apart and with the sashing and sewed back together, I was back at the original size. no need to figure the math so they would all fit back together correctly like using a different width of sashing. You do have to pay attention to which sides of each piece you need to put sashing on.

http://i31.photobucket.com/albums/c3...pstloxfvi3.jpg

http://i31.photobucket.com/albums/c3...pskqcaczfu.jpg

Something like this pattern is made simply by using a narrow sashing. If you are trying to figure out sizes, use graph paper to plan it out (reminder to add your seam allowances). I did a wall hanging of a beach scene and simply added the 'stain glass leading' as an applique using a very narrow bias binding. I found using the double sided tape worked great on the tiny curvy spots.

Thanks for all the ideas everyone - lots to think about!

Oops. Yes, you are so right, cut 3/4” to finish at 1/4”!

You can also do a "reverse" stained glass. One large piece of black fabric (the size you want your quilt to be PLUS an extra allowance on all sides for sandwiching and quilting). You can then applique (any technique) your color blocks onto the black fabric. Carefully cut away excess leaving just a narrow bit of black. This technique works really well when doing stained glass pictures (think Tiffany windows, etc). Hope this makes sense.

I have done this technique... super simple! https://ludlowquiltandsew.co.uk/2014...quilt-pattern/

I just finished one and the pattern was free just go to Ludlow Stained Glass Quilt.

http://www.robertkaufman.com/assets/...20Heritage.jpg has a pattern for a quilt you could go by and make narrower. I always just use graph paper to draw my patterns like this, which does take more time and I do not always get each step, and must rethink it.

I'm working on one now, a free pattern called Prairie Glass Squared by Jessica Levitt. She suggested not cutting the black strips to length until they were sewn to the pieces. It's been a fast and easy way to do it, and kind of addictive, like string piecing.