Firming Up Fabrics with Gelatine
A solution is made – 1 teaspoon of gelatin (not a whole packet) is introduced into 16 ounces of tap water; let it sit for 30 minutes. Heat a quart of water to boiling, and add the gelatine mix to the quart of hot water.
Here's the fabric soaking. We left it in for an hour.
The water's now poured out.