Dyeing a shirt gray may seem like a tricky process, because you need to use black dye in a certain way to get gray. It is actually a fairly simple process to dye a fabric, such as a plain white cotton T-shirt to a shade of gray. You essentially need to just use less black dye depending on what shade you want. Follow a few steps to dye your fabric in just the right shade of gray you're looking for.

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Dyeing a shirt a solid gray color takes a little more work than tie-dye.

Step 1

Weigh your shirt on a kitchen or postal scale.

Step 2

Machine wash the shirt on the "hot" setting, which serves to scour the fabric.

Step 3

Put on the rubber gloves and an apron or old clothes.

Step 4

Use 1 tsp. of black dye powder for each pound of fabric for a pale shade, 3 tsp. for a medium shade, 6 tsp. for a dark shade and 12 tsp. for dark black. Dissolve the dye in two cups of room temperature water per pound of fabric and set aside.

Step 5

Prepare the dye bath in the bucket, adding 2 1/2 gallons of room temperature water per pound, along with 1 lb. of salt for light gray, 1 1/2 lbs. of salt for medium and 2 lbs. for dark. Add the dissolved dye and stir some more.

Step 6

Add the fabric and stir continuously for 10 to 15 minutes.

Step 7

Dissolve 5 tbsp. of dye activator for light and medium gray fabric, and 7 tbsp. for dark gray, in two cups of warm water.

Step 8

Remove the fabric from the bucket and pour in the dye activator. Stir it a little and put the fabric back in the bath. Stir continuously for five minutes and then stir every five minutes for the next hour.

Step 9

Remove the fabric and rinse thoroughly in a bucket of room temperature water, changing the water three or four times.

Step 10

Wash the fabric in hot water along with 1/2 tsp. of synthrapol per pound of fabric. Do this twice if you are going for a dark gray. Rinse with water and repeat the process until the rinse water is clear.