My calculations of 'how much dye is needed for this piece of fabric' were a bit confusing, at least to some of you. So, let's make my steps clear in a blogpost. (And let's make sure, this is not what Ann Johnston is teaching, it's just the way I prefer to do it, because it makes life easier. This way of thinking and calculating was a result due to the high cotton and dye prices in Europe, and also, not wanting to waste any dyes for environmental reasons).
First of all, I make all colours in the same concentrate, 10%. That is, 10 grams of Procion MX powder to 100 ml. of water (1 deciliter). If they are all the same, my brains don't have to think that much, if I find a bottle in my cupboard. It's always 10%.
To avoid messing around with dye powders, I use those juice bottles with a big opening. Put them on my scale and press Tare, so it resets to zero even with an empty bottle on top of it.
Tighten the lid firmly and then I start shaking.
Can't make it easier then this. I even forgot to wear my gloves and actually, if I am careful, I don't need them.
NB for this special project, I mixed on forehand Orange: 7 grams of Yellow MX-3R with 3 grams of Red MX 8B with 100 ml. of water. And for the blue: Turquoixe Blue MX G 9 grams with 2 grams of a black without a name ;-) with 110 ml. of water.
So now that I have my 10% solution premixed ready, I start calculating how much solution I need for a full colour. I know from experience that I need 20 ml. of a 10% solution for a FatQuarter of cotton fabric (each quality). I roughly estimated that this piece was 4,5 FQ's so I needed a total of 90 ml. dyesolution.
I divided the total amount in two colours, 45 ml. of an orange, 45 ml. of a blue.
And the good thing about this way of calculating is that you can remake your unique pieces, look at this picture, one day later, same amount of dye, same tray. I only was too impatient I guess or I didn't press the same time, the piece at the left hand is the newer piece. But you can see that I am pretty close to the original.