Choosing a dyeing pot

The best materials for a dyeing pot are either stainless steel or enameled steel.

Enameled steel canning pots are inexpensive for their size; you can find a new 20-liter (5 gallon) canning pot for under twenty dollars, or a 33-quart (8 gallon) canner for under fifty. The only drawback is that the lining of cheap enamel pots will chip easily. Once you get a chip on the inside of an enameled steel pot, the reactive steel underneath will rust, which can dramatically affect the colors produced by many dyes. However, you can repair the chip by painting over it with a heat-resistant enamel paint (don't use the pot for several days after the paint has dried). This is not safe to do with a cooking pot, since the paint is not food-safe, but it's okay for a dyeing pot.

My personal preference for a dyeing pot is stainless steel. It will not react with acids or bases, and it will not release metal ions in concentrations high enough to alter the color of a dye. You never have to worry about small chips or scratches. My own dyeing pot was relatively cheap, without an aluminum layer under the stainless steel, so it's thin enough that I would not like to use it for cooking food; soup would tend to stick on the bottom. I haven't found this to be a problem for dyeing, though. Even a cheap stainless steel cooking pot is usually more expensive than an enamel pot, especially in the largest sizes, so an enamel pot may bepreferable unless you will be using it repeatedly. A good source for 5-gallon and 10-gallon stainless steel pots is a beer-brewing supply store, such as Defalcos.com, which as of this writing sells a lightweight 5-gallon stainless steel brewing kettle for $35.

You'll need to make sure that your dyeing pot is large enough for whatever you're dyeing to move around in freely. If the pot is too small, the fabric will not move freely in the dye, and you will get uneven results. (This effect can be exploited for multi-color designs in low water immersion dyeing, which does not require nearly as large a pot.) To dye one pound of fabric (weighed while dry) to a solid color, you'll need a pot that is three gallons in size, or larger.

The general rule is that you don't want to use a metal that will react with either your dyes or the auxiliary chemicals you use with them. Aluminum is out, because you cannot use it with either acids or bases. Most dyeing recipes call for an acid such as vinegar, or a base such as soda ash (though never both together, since one will neutralize the other). Aluminum is also used as a mordant for natural dyes, and may affect the colors produced by some dyes. Cast iron is good only for dyeing black and especially dull colors, because the iron ions interact with many dye molecules, including both natural and synthetic dyes, in a way that makes the colors much darker and duller. Old dyeing manuals say that iron "saddens" the color of the dye. Copper and tin have very different effects on the colors of dye, changing the colors of some dyes unexpectedly, but copper pots are too expensive to consider for use in a dyeing pot, anyway.

Choosing a pot for dyeing polyester in can be a little easier than for natural fibers. Although I would try to avoid using aluminum even for dyeing polyester, Jacquard Products, the makers of iDye Poly, say that you can use an aluminum pot with their polyester dye. However, the recipe that PRO Chemical & Dye recommends for disperse dye calls for pre-scouring the fabric with soda ash before dyeing, and using a little citric acid or vinegar in the dyebath itself; neither of these is a good idea in an aluminum pot. Better to stick to stainless steel or enamel pots, which have the advantage of also being useable when you want to use a different type of dye. As you probably already know, it's not considered to be a good idea to reuse a dyeing pot for preparing food, since no textile dyes have been tested for safety for use in food, and there's always the fear that a little contamination will remain in the pot, though the risk is low for a unscratched stainless steel pot. While most of the dyes used by hand dyers are low in toxicity, not all of them are, and it makes sense to be reasonably careful.