We started by using a potato peeler to shave slices from the Fels-Naphtha bar. You can use a grater, but we found the potato peeler worked better. The soap was just the right consistency for the potato peeler.
Once the soap was "peeled" we poured it into 4 cups of hot water and continued heating it on the stove. You do NOT want the water to boil, but it must be very warm to melt to the soap. I stirred it continuously, and smashed the pieces of soap against the side of the pan. This took several minutes.
Below is what the "melted" soap and water looked like.
While I was melting the soap, Renda filled a 5-gallon bucket half full of hot tap water. (Anybody need any 5-gallon buckets, I have dozens of them in my barn, seriously.) After the soap was completely melted, we added one cup washing soda and one-half cup borax to the bucket, then poured in the melted soap mixture.
I stirred this after all the ingredients are added. The water was hot, so it didn't take long for the powder to dissolve. After the powder was completely dissolved, we filled the bucket full with hot tap water. This is the full 5-gallon bucket of our homemade laundry soap.
We covered it and let it set overnight, and the next day, this is what it looked like.
It had separated, and was almost "stringy" in consistency. I took a large spoon and stirred it and it mixed together nicely. I filled a clean milk jug with a gallon of homemade soap and took it home. When my Tide bottle is empty I will fill it half full of the homemade laundry soap and half full of water. When I need to do laundry, I will use 1/4 cup of the new soap in my front-loading machine. I wish you could smell it because it is the most "clean" smell you'll ever smell. I still have a few days worth of Tide, so I will let you know what I think after I do my first load. Oh, by the way, the cost of the ingredients for 10 gallon of homemade soap was around $2. And that will make 640 loads for a front loading washer. That's a lot less than Tide.