These 2 bottles pictured above are a perfect example of a few things in soap making. Weight and volume are not the same and scales are important to have! My husband actually pointed it out which got me thinking - he does not make soap (thank goodness) - when he said "Why'd they send you half empty bottles?" as I unpacked my supply haul. He's a "glass half empty" kinda person, can you tell? Well, I had news for him. This is a case of the glass being half full not empty!
One bottle is glycerin (for mixing colorants) and the other is sodium lactate (for my soaps). They each weighed over 16 ounces, which is good because that's what I paid for :P! To compare, below is a picture of the exact same packaging, but different product:
You need to have a fairly accurate scale and a digital one at that, one that weighs in grams and/or tenths of ounces at least to soap properly. Especially when making smaller batches of stuff! Being off by just a tad in a small batch can be a BIG disaster! To me, it's like grains of rice....another dorky analogy...
If you need 4 grains of rice, but you have 5, it's a noticeable difference. Not only can you see it, but the percentage of extra rice is 25% of what you should have. Now, on the other hand, if you need 50 grains of rice and you have 55 you are less likely to notice the 5 extra grains aren't you? Then, when you do the math that's only 10% more than you should have - a smaller difference. Soaping is much like that when you look at the grand scheme of things.
I have found that the bigger a batch is of something the more forgiving it is to an extra tenth of an ounce of something, but the smaller a batch is the more accurate I need to be...in comes the part about a good scale! If your scale only measures in crude ounces or doesn't have grams as an option it becomes far harder to end up with accurate amounts of oils and such...which leads us to the next issue. Weigh everything every time!!! Don't get all cocky and start using your measuring cups or guessing and eyeballing stuff - eventually this will blow up on you.
That's right, you heard me...WEIGH IT OUT WITH A SCALE! Sure, there are some soapers out there who use recipes that have measurements in cups and teaspoons. Maybe it works for them, kudos to them, and good luck. I've even seen videos on youtube where people are making soap using what I call "kitchen measurements" - those cups and teaspoons I mentioned instead of a scale. In my opinion they are purely lucky! Clearly, as demonstrated by the two different products being two different VOLUMES in the same exact bottle and pictured above, one cup of sodium lactate is going to weigh more than one cup of avocado oil. Weight and volume are not the same thing and are not interchangeable when it comes to soaping! Take the chance when you bake a cake...not when you are making a loaf of soap....there's no caustic lye in cake batter but there is in soap batter. See where I'm going with this?
Be patient, be accurate, and invest in a decent quality digital scale and 99% of the time your soap will turn out perfectly (there's always that oddball batch...it happens...soap gone wild and such). But if you gamble with your weights and measurements be prepared for more failure than those of us that don't. Accuracy and attention to detail are what make a really good soaper. We all have a bad night or a bad batch, but your odds are so much better when you are accurate!
Anyways...off my little soap box now and back to my soap room. I shall have pictures in the next day or two of the 2 loaves of soap I cooked up this evening :) Until then my friends, stay dirty!