what about a 'stay stitch' before cutting, to keep your angles true....

Perhaps liquid starch would work for you? You can put it in a spray bottle rather than using the aerosol cans. I don't know if there is an entirely unscented one. I don't have an allergy as such to scented products, but I don't like them. I quit using fabric softener altogether after Costco quit carrying the unscented one. I don't understand why manufacturers think they have to add scent to everything.

Now that I think about it, you may be on to something here. :)
I will give it a try. I'm always up for learning something new. :)

Use good quality flanel (not saying yours isn't ) and starch starch starch before cutting. I like working w/ it because it is easy to match up since it sticks together when you sew it.

The only liquid one I can find at Wal Mart is scented. I'll check a special catalog I have for environmentally safe products. I agree with you 100% about the manufacturers. :) They claim all of the consumers want scents. I don't believe they are asking everyone. :(

I can sympatize with you, Tropical. I have problems with perfumes, etc. I use MaryEllens Best Press unscented. It is in a spray bottle, not aerosol. You might be able to use that.. It doesn't flake, has no starch in it, but gives a nice crispness to flannel to make it easier to work with.

You could also use spray sizing. That is what manufacturers use when they make fabric so it looks nice in the store. Also- All cotton, including flannel, has a stretch across but not down. When I work with flannel, I make a small clip on the not stretch edges, so that when I put them together, I can put stretch to stretch, and no stretch to no stretch. This may help you too, just remember to make little clips, so that they end up in the seam allowance.

Sometimes flannel will need multiple wash dry cycles before it's done shrinking. It also shrinks in one direction lots more than the other. I'm wondering if it was not done shrinking with your single wash and when you pressed it(with steam??) it shrunk again. If you still have an uncut piece, try washing and drying again.

If you want to sew with flannel after washing out all the sizing, you HAVE to use starch. The weave is too loose. If you can't use starch, try Mary Ellen's Best Press. I have a bottle of it, but haven't tried it with flannel yet.

Yeppers, that is exactly what I do...starch, starch, starch.....just finished a 56x56 rag quilt with flannel
I use Mary Ellen's best press for everything...it works well with flannel