Ever notice the manufacturer doesn't always get the fabric folded and rolled onto the bolt square? This is one of the main reasons I choose to pre-wash. Pre-washing gives me a chance to re-square it before I refold it. It can be an inch or more off in a single cut.

Here's what I do:

Fresh out of the dryer - hold it selvage to selvage let the fold fall. Is there a diagonal "bubble" in the fabric? If so, slide one of the selvages right or left - when it hangs completely flat, it's right.

Now look at the cut edges again. 85% of the time, I've lost some usable fabric from the original cut. Can't discover this unless you pre-wash.

So strips cut from an unwashed piece, may not actually be on the straight of grain and sometimes this shows.

Hope this helps someone...

Thanks for the info. I, too have noticed this. Although I don't always prewash I always check my fold this way before cutting.

I do this as well. I prewash for a lot of reasons and this is one of them. Additionally, I always give a tug along the bias in both directions to coax those warp and weft threads into alignment before doing the fold you describe.

I've also had some fabric where the selvage shrinks a bit so I've had to clip it every few inches to get the fabric to lay flat to cut or fold. (I try not to buy fabric from China.)

That's what I do too. Because of fabric being 'off' when sizing added, it is almost impossible to get it straight without washing out the sizing. And you can tell what the fabric will really feel like after washing. I bought a piece of Benartex that was a little stiff. I thought washing would soften it. But it is still stiff. I won't use it in a quilt.

yep yep yep..... here too....

You described the process well. I think it is one of the more important steps.

I've also decided that once it "lays flat" - I'm not going to fight with it any more and will use it "as is"

I've tried doing the diagonal "tug" - but after washing and drying, it seems to have found its "natural mode" - and many times after doing the tugging, it just goes to where it wants to go.

I'd much rather have the uncut fabric relax to it's natural state and lose some to scraps.
If it happens after the quilt is finished the blocks get wonky and just don't look right to me.

The trick to straightening is to pull on the opposing selvages to straighten. This is a basic technique taught in home ec. Then you press the fabric with steam keeping the grain aligned.

Julia