here, but if you've read any of my recipe posts, you know that i'm an inveterate tinkerer, and have to fiddle with anything i try.
The original version calls for Fels-Naptha soap, but even though it no longer contains any napthalene, the label is disturbingly vague about what it does contain. I decided - knowing you can get soap flakes of various things like Ivory in the laundry aisle - to try using a plain, unscented Castile soap. The other ingredients are washing soda and borax, both cheap and readily available at the grocery store. Since i was using an unscented soap, i also added in a few drops of lavender essential oil.
The sum total of the procedure is to grate the soap and then mix it with a cup each of the borax and the washing soda. I used about 10-12 drops of lavender oil to scent the whole batch, and mixed that in well before packing it in a couple of small mason jars - i was tickled to find in my stash of pint jars one that reads "Naturally Fresh," so of course i had to pack some in that. You only use about a tablespoon per load (got myself a cute little coffee scoop at the thrift store that works very nicely for measuring).
The report from the field test? It works, and it works quite well. I tried it on an musty set of sheets that was still smelling funky after three rounds with the commercial detergent, and the sheets came out de-funked. It looks like it will be significantly cheaper than the stuff i was buying, and it doesn't take much time to prepare.
Notes for next time: add a little extra soap - the Fels-Naptha bars are 5.5 ounces, and the bar i used only 4 ounces. It's supposed to be low-sudsing, but i think it could use a wee bit more.