Quick quiz question for you: Lucy and others pointed out that I haven't put in the total amount of solid material you need on the requirements list. That is because:
a) it depends on what size quilt you are doing
b) I am lazy
c) Maths is not my strong point
d) all of the above.
Sigh. I've done some calculations. Here they are:
All clear now? ;) Can someone please invent an app to tell you exactly how much fabric you need?
For each square you need a 12" backing square, and 2.5 inch sashing. If you are using the bias strip method of joining your QAYG, you'll need enough bias in the same colour to join all the blocks one side. According to my calculations, that's approximately 3 yards. But choose a solid you can get again in case I'm wrong. It's a solid. You'll use it again.
I use White-n-Warm or Warm-n-natural cotton batting mostly. I'm just using that for my QAYG squares as I'm not sure how batting of different types, weights or brands would join. (Might be a bit uneven and messy. If you've done it successfully, let us know. If not, stick to the same type of batting for all your squares).
I tried special batting joining tape I bought at the craft fair. Not sure what sort I got, but it was poly based and kinda melted. Was not too impressed with it. Decided to try plain old lightweight fusible interfacing, the kind that you use for dressmaking. Worked like a charm.
Basically, Cut 2" strips of lightweight fusible interfacing (one sided).
Cut the batting pieces so each has a straight edge.
Butt straight edges together on ironing board. Iron your tape over - voila!
You don't even need to trim until afterwards. Your batting squares need to be at least 11" square. Bigger is fine. You don't need to be precise about it - it will all get trimmed back to 10.5" afterwards, but you need the batting to be bigger than your top square in the first place as things move around when quilting.
Preparing the blocks
2.5" strips. 6.5" squares. Solid colour sashes the squares thus:
I cut my backing squares to around 12".
Sandwich backing, batting and top piece.
Stitch in the ditch around the coloured square to anchor the layers together. (The batting I used is nice and 'sticky' so being such small squares and having such a good walking foot on the Bernette, I didn't even need to pin. If in doubt, PIN!).