Thank you to Peckish (Peggi) who just last week introduced me to (my new best friend) STARCH!!!! Whoo hooo! I can't believe the difference it makes! I started with just a light spray (Faultless brand Heavy Starch- Original Fresh Scent), and that was ok, but when I really put the starch to it (pieces were literally wet), it was much better. (Yes, I screwed up and forgot to apply the starch BEFORE cutting).
But wow, what a difference in sewing! Love it, Love it, Love. IT!

Sorry; I know that my commentary didn't address the OP's question AT ALL...but I just thought I'd put in my 2¢ :)

I prefer using fabric sizing spray, it makes it somewhat stiff

Thank you I am going to try some Sta-Flo!!!

Another sta-flo fan here as well. The cost difference is amazing. I mix up a bit at a time, a 1:1 ratio and use a regular spray bottle. It's a snap to mix up as needed but will also last for longish periods just sitting at room temp with no problems. And I think it does a far better job of any of the commercial spray starches or sizing.

my formula is 2 tbsp cornstarch to 2 cups water, put in spray bottle and shake. Works well for me.

I've never boiled it so don't know how that does...but am satisfied as is. I always have cornstrarch on hand anyway for cooking so this makes it double worth the buying.

Also I never have to run to the store to pick up starch.

I don't use starch...I use Mary Ellen's Best Press, a starch alternative. No residue, no mess, comes in several pleasant scents or unscented. I bought a whole gallon and use it to refill my spray bottle.

I too use a homemade recipe
Stir 1 -2 teaspoons of cornstarch into a bit of cool water to dissolve
Stir in 1 cup boiling water, and stir for one minute to fully dissolve cornstarch
stir in 1 cup cool water.
let sit until cool enough to handle and pour into a spritzer bottle.

That's it! All natural, made for pennies, super easy and friendly to you and the environment.

You can add some lemon juice (2 teaspoons) if you like, but it's not necessary. Shake well before each use and throw away any you don't use within a week. No preservatives means it doesn't last as long as the commercial stuff, but given that it is so inexpensive and easy to make, this is not a problem.

I have been using cooked starch for years now. I couldnt find Stay Flo where I live so I made my own. I dont have a recipe per say, I just know how its supposed to look and feel as I'm cooking it. I recommend adding washing borax to the starch, it will preserve the starch for a really long time. Without the borax the starch will go sour, it doesnt take much, just a couple of spoonfuls.I also add a spray of my favorite lavender body spray, just one push on the pump. It gives the starch a nice smell and doesnt change the nature of the starch. I have a half empty pickle jar of my last batch in the fridge, its about 5 months old now and still as fresh as the day it was made thanks to the borax. I normaly make a batch every 6 months or so and keep it in the fridge.

i had no idea that starch was made from corn starch. i thought it was made from some strange and magical mixture. LOL it's amazing what i learn from this group!

I like Niagra concentrated starch and mix it up to the strength I want. it has a very pleasant scent. I prefer to mix my own rather than be throwing empty cans into a landfill. One bottle last me a long time.
peace