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Cold Process Soap Making: Lye Questions and Answers

So, you're ready to venture into cold process soap making.  Before you start in with your first batch, make sure you familiarize yourself with lye safety.  Here are some of the most common questions about lye use in soap making.  Read through them and if you have a question that isn't answered, please feel free to ask!

What is lye?
Lye is a caustic that today is most often used as a drain opener (and is one of the key ingredients in Drano.)  Although it sounds like a horrible addition, it's a necessary ingredient used to saponify the oils, turning them into lovely soap.

Can you make cold process soap without lye?
Nope.  It's not possible.  But don't worry.  So long as you're careful it's perfectly safe.  And when cold process soap is properly made, there won't be any lye in your finished soap bars.  

If you're not comfortable using lye in your soap making, try the melt and pour method instead.  (Check out this article for more melt and pour soap info.)

What type of lye do I need?  Is any brand OK?
You can only use 100% lye in your soap making.  If the package does not specifically say 100% lye, you can't use it.  You'll be looking for either Roebic or Rooto brands (they're the only brands I know of that are good for soap making.)

Definitely don't use brands like Drano, etc.  They contain lye but also lots of yucky chemicals that won't be great additions to your soap. 

Where can I buy it?
 Best place to find 100% lye is at the hardware store, but some grocery stores sell it too.

At my local store, they keep lye behind the counter and I have to show my ID before they'll sell it to me.  What gives?
Lye can be used in the manufacture of drugs, so sometimes it will be kept locked and you'll be asked for ID.  Even if it's on the shelf, I always like to tell the cashier what I'm using it for.  It saves me from those funny looks I get when I'm buying several canisters of the stuff and nothing else. 

How did they make soap before you could buy lye at the store?
Our pioneer ancestors used to make their own caustic using wood ash and water, but it's a long and arduous process.  My colleague has some great info on how wood ash lye is made.

Can I make my own caustic then?  
Some hard core soap makers still create their own caustic like the pioneers did.  So, if you really really want to make your own lye for your soap, you can.  But there's no way to gauge just how strong your homemade caustic is, which can leave you with lye-heavy bars.  It's really much easier (and safer) to buy lye.  I've made soap for years, and have never made my own lye.  I don't think I ever will.  
Yikes!  The warnings on the canister look scary!
Yeah, they do.  But try not to let them frighten you.  Sure, lye is caustic and can be harmful if handled improperly but it's not anything to be scared of.  Do you use bleach in your home?  Have you ever used Drano on a slow drain?  Lye is not any more dangerous than those products.

You might be surprised to learn that olives and pretzels are given a lye-water bath.  And we eat those!

So handle lye carefully, use precautions and common sense, but don't let the warnings stop you from making soap.  Take a look at this piece about lye safety rules, and follow them, and you'll be fine.

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