I would like to experiment (being new to this expression of Origami) with creating origami tessellation patterns using fabric of some kind rather than paper. If anyone has experience with this, what fabrics do you feel are better suited for this initial foray, and does the fabric benefit from a stiffening agent in advance? Thank you!
Cottons which take folds well and hold the crease when you rub or iron it in. I would look for a woven fabric and not for a certain weight but I would experiment with several which I have around in the house.
I know that sail makers used to use a sail rubber when having made a fold in the sail before sewing.
Sail cotton (also called cotton duck) is about as heavy as you can get it and still be able to work it by hand.
Whether you need to stiffen it depend on what you want to do when the initial folds are in and on the quality and weight of the fabric.
Some other fabrics will work, if you use an iron or steam in the folds. Traditionally woolen fabrics were used to make pleated skirts where the folds worked pretty much like the patterns you plan to make. Steaming those fabrics was a specialist job, but simple patterns should be within reach for people at home.
The best is to experiment. And please come back to tell use what worked for you.
The best option for fabric origami is lightweight polyester because it can still hold the pleats after being washed. From Sewguide.com:
Polyester is the favourite for making the pre-pleated fabric. On polyester, the pleats formed remain the same for the life of the fabric. The soft, smooth and lightweight and flowy nature of polyester fabrics, especially polyester chiffon fabrics makes it a popular choice in dressmaking. Other best fabrics preferred for pleating are silk and wool.
You can still get the same advantage from a blended fabric of at least 65% polyester content.
There are several natural types of fabric that pleat very well, like linen or cotton but these also tend to accumulate additional creases from being handled or worn. That makes silk or wool suiting the best natural options.
The most important secret lies in the process of pleating. Synthetic fibers pleat when they are hot, natural fibers when they cool down. That means the safest way to pleat any fabric is to get it hot and wet, put it into the desired shape and hold it there until it's cooled and dry again.
If you're pleating fabric with an iron, pass the iron over it (steam intensifies the creases) and then keep the fabric in position until it's cooled down again. You can use a wooden board called a "clapper" to press the fabric while it cools down.
For fabric origami you need 2 thin cardboard pieces that are prefolded in the tessellation pattern. Sandwich the fabric between both templates, fold them up and bind them tightly with some strings or ribbons. Then steam the whole package for half an hour (or longer for thicker packages containing lots of fabric) and let it cool down completely. You get a better result if you can pressurize the fabric package while steaming, for example in a pressure cooker. Only unfold the package after it's cooled down all the way through.
I've heard or read somewhere that adding vinegar to the steaming water is supposed to help permanently pleating the fabric, but I cannot find a source right now.