Teach Soap

Typically over the 4-6 week period how much water is actally lost? I mean if you have a 5 oz soap will you lose a 1/4 oz or 1/5 oz? Will it shrink overall? If I cut my soap to be 3.5x4x1. Should I cut it 3.5x4x1.5? So the extra water loss doesn't really shrink the soap.

Yes, I have made several test batches. I am wanting to make more. I understand that alot of it it is practice and testing. But in the regards that I don't want to waste several batches practicing on thick to make them. So is you have any ideas please help. Is there a standard amount of water lost per batch? Does the lye calculator help tell you? And I just haven't figured that out yet?

Any help is welcomed!!!

Thanks,
ginger

Water loss depends on how much water you started out with. A recipe made with "full water" has more to lose; one made with a water discount/stronger lye solution has less water to start with, therefore less to lose.

Yes, the bars DO shrink over time. I have bars that were fully cure for 6-8 weeks, then labeled with cigar-style bands. Some were set aside, and months later - the labels are loose because the bars have shrunk/dried more.

Is there a reason that your bars need to be an EXACT size?
I make and cut mine to the size I like, and don't worry about shrinkage - try to label or package after most of the shrinkage has occurred. If I was really interested, I could weigh and measure the bars before and after, and get an average amount of shrinkage both in weight and dimension. Of course, with continued curing, you'd have to repeat those measurements later.

Legally, soap is sold by weight, not dimension anyway. I think people are aware that handmade products can vary a bit.

Yes, it would be nice to find away around the testing and numerous practice batches. Good luck with that

If you really really really need your finished, cured bars to be a precise size, then testing is your only option.

sorry - I am pretty sure that is not the answer you were hoping for.

I made some measurements some time ago and my cp soaps generally lose
about 10% of their original weight during 6 weeks. I use 33% lye concentration. The difference is
noticable mostly by width. Can not give you more information about high or thickness changes
as I was experimenting with the molds and continue to change them so I have no relevant data on this.
Hope this helps at least a bit.
Good luck with your soaps!

Thank you to those who answered. I just was wondering by everyone's different experience. I have several different molds and cut my soap different thicknesses. I have looked at online stores that sell cp soap and give dimensions and the oictures like bugger than what the size they specify. So I was curious for everyone how much water loss happens for them.

Thanks,

Ginger