Those sawtooth borders....

....it sounds silly for a quilter of my experience to carry on over simple half-square triangles, doesn't it?

Well, it's not the triangles, it's those 37 seams......if they're off just a smidge, the whole thing comes out the wrong length, and I can't STAND wobbly borders or, on the 'other side of the coin', borders that are too tight, so that they pull on the quilt !

With the first triangle border, I sewed all of the half-squares together into pairs, and then measured........2  x 2 1/2 inch (minus seam allowance eaten  up) = 4 1/2 inches.  Each set measured perfectly right.  Then I joined those sets into sets of 4 squares = 8 1/2.  Then 8 squares........16 1/2 inches.  Each time they measured perfectly right, and I thought,....wow, no problem.    So, I went ahead and kept joining until I had 38 squares joined for a 76 1/2 inch border.  Well, when I measured the finished border, it measured a full INCH too long ! 
How did that happen?  I don't know !  But it meant alot of resewing just one thread farther over until I got it right.
This wouldn't have been a really big deal, except that I had pressed the seams open as the pattern suggested, for ease of bulk, and now the seams didn't press as prettily.

On the second border, I'd sew and measure, sew and measure.  Before long, the longer and longer units that were joined were measuring too short, but I kept going anyway (worried).  When I finished and measured the whole thing it was perfect ................... ??????????????????????????

So, that's the story.....I had not made a pieced border in a very long time........now I remember why.   But, boy, is it worth the extra effort.  This quilt is going to be NICE.......back to work !