Short note about bias tubing

This pattern I'm working on has you sew bias tubing using a scant 1/4" seam allowance. I don't have a problem with that in theory, but the thing is, you're using a bias strip 1" wide and you're supposed to stretch it while sewing. In this case, at least with the particular fabric I'm using, you'd end up with the seam allowance being too wide to fit flat inside the tube.

I think a better plan for these narrow-ish tubes (if you're turning tubes at all — RTW doesn't bother with this quite as often as home-sewing patterns seem to; sometimes they just fold and edge- or topstitch) is to focus on keeping the seam allowance just slightly narrower than the tube itself. So you're sewing just a bit over half the width of the folded strip from the folded edge. For thick fabrics, the seam may need to be slightly closer to the cut edge than for thin ones.

 
Ideally the seam allowance width will stay consistent throughout, but if you haven't cut perfectly accurately, it's more important to keep the stitching the same distance from the folded edge. No one will see the exact width of the seam allowance once it's inside the tube.

This is all assuming there isn't a very precise with the turned tube must be, but in general, tubes made this way will end up about a quarter of the width of the cut piece. These particular ones are meant for tie ends and are 1/4" wide finished.