Soap Flakes & Cloth Nappies
We sometimes get asked about soap flakes and natural soaps for washing nappies. Pure soap flakes, rather than detergent, give a much softer feel to nappies and wraps. They are particularly useful when washing wool wraps, because they retain the wool fat. Where it's certainly possible to use soap flakes, we frequently find that they just don't give a thorough enough clean for cloth nappies, which may lead to problems with skin sensitivity and lowered absorbency. It is also against some brands' warranties. If you decide to use soap flakes to wash your cloth nappies, bear the following in mind:
Effect on absorbency
Soap is primarily made of fat, animal fat, or vegetable oil (e.g. olive soap) and sodium hydroxide. This explains why soap is alkaline and not great for sensitive skin. (You see, we do beauty tips free of charge here as well!) It can leave a film that can affect absorbency. But the main factor seems to be hard/soft water. Hard water will leave a 'fatty scum' on the fibres, no matter how much you rinse, and that will affect absorbency. Soft water is better, as the soap dissolves more completely. Soap flakes leave cotton very soft to the touch, but not as absorbent.
As for clogging the machine, it's back to the hard/soft water thing. It shouldn't be a huge problem in the dispenser drawer, but can be in the waste pipes, because you are getting rid of the scummy water at that stage. The inside of the pipes can get clogged until they are totally blocked. However, a good dose of very hot water and washing soda crystals does wonders for that. It de-clogs the machine as well as the pipes.
Too much froth in the washing machine inhibits the cleaning process, which is why you should be really sparing when using soap flakes instead of detergent. Adding them direct to the drum rather than in the dispenser drawer makes sure that all the flakes get to the nappies rather than stuck on the path from the dispenser drawer.