Lye water - why do I loose weight/volume when mixed?

[RogueRose]

IDK if any of you have noticed this or if I'm the only one who experiences this but when I mix my lye water I always seem to end up having less than the sum of what I added. So if I add 1kg water and 400g lye I might get 1290-1370g of solution.

I don't know if there is water boiling off and whether it would happen less if I added the lye more slowly and kept the temps down.

I'm curious what others have found and what they think is the cause and how it effects the soap.

 

[Lion Of Judah]

interesting ! i never ever looked at my lye water solution like that before , i just measure water , measure lye , add together and go from there . you may need to take a closer look at everything leading up to measuring and mixing your water and lye together and check if your scale is ok.
next time i make some soap i will take notice of my lye water before and after .

 

[Lindy]

It is going to be caused by evaporation from when the solution heats up. You can see the steam.

 

[IrishLass]

It's what Lindy said^^^. When I make my 50/50 master-batch lye solution for long-term storage, I tend to lose about 6 to 8 grams of water to evaporation when I'm mixing. I just add the missing water back in right before I cover my mixing container.


IrishLass