Homemade Laundry Detergent Powder Recipe! {Large Batch}- how to make washing powder washing soap for baby ,Sep 10, 2012·So I decided to make a Homemade Laundry Detergent Powder form of homemade detergent. I had everything I needed on hand (I finally used the Fels-Naptha my mom gave me when I got married, 13 years ago), so I hung up the phone and proceeded to make a small batch of homemade laundry detergent.3 Ways to Make Your Own Laundry Detergent - wikiHowFeb 28, 2020·To make your own powdered laundry detergent, grate 10 ounces (283 g) of bar soap, like castile or Zote laundry soap, over a large bowl with a cheese grater. Transfer the soap flakes to a food processor and pulse the soap for 1-2 minutes until the flakes have been reduced to a powder.