​Does anyone else do this...?​

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wearytraveler

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If my recipe calls for, let's say, 9.62 oz. of water I always round it down to 9.00 oz. when it comes time to measure I've been doing this since I start making soap and I'm just wondering if anyone else does this.
 

toxikon

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I'm definitely a lot more precise! I aim to be about ± .05 oz.
 

dixiedragon

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I would round that down to 9.5, but not all the way to 9. Now, if I was doing that recipe and using a 33% water:eek:il ratio vs the standard 38% the lye calculators start off with, it may very well drop from 9.67 to 9. But wouldn't round it there myself.
 

Steve85569

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What E.G. said.
I weigh in grams and try to be as precise as possible.
Like others said, if I want a higher lye concentration I simply start with it.

I usually do run a higher lye concentration so reducing the water may cause serious problems. If memory serves me lye wants to be at a minimum of 1:1 with water to safely and properly dissolve and not just go in to solution.

Lye is not my friend. It wants to eat me alive.
 

IrishLass

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I do the same as the good Gent and Steve- I weigh everything in grams and try to be as precise as possible.


IrishLass :)
 

Gerry

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I round my grams. If it calls for 2066.7 grams of lard, I go for 2067.

But seriously, I don't think rounding by ounce is a great idea, unless your batches are like 50 pounds of soap. Being off by 14 or 15 grams can be pretty significant with small batches, especially if you're measuring lye.
 

DeeAnna

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I'll concede that water is not nearly as critical to measure carefully for safety, since water doesn't affect whether a soap is lye heavy or not. But Steve makes a good point about the max NaOH concentration.

Also, the change of just a percent or two in lye concentration can change how your recipe performs -- whether it gels easier or not so easily, how fast or slow the recipe traces, etc. Looking at my current favorite recipe and translating from grams to ounces, the recipe calls for 16.7 oz of water. If I rounded that down to 16 oz, the lye concentration would increase by 1%. Whether that's significant or not depends on the soaper's point of view. For me, that's a definite change.

I use an elderly but still useful lab scale that weighs to 0.01 grams. While I don't get that finicky for soap making, I do weigh soap ingredients to whole grams like Irish Lass, Steve, and The Gent. I figure there is enough unknown error in a soap recipe due to estimates for lye purity, sap value, etc. I don't need to add to the error by rounding any deeper than that.
 

shunt2011

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I'm another one who always measures in grams. Most accurate measure for me.
 

Scooter

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Stick to what the lye calculator tells you. If you are not happy with the water amount, change the lye concentration on the calculator. Rounding numbers here and there can cause bad habits.
I tend to finagle my recipe on soapcalc to where my oils are all integers in ounces and then I use grams for the lye. I have been known to finagle my recipe to where everything is in integers... and that usually means I have a weird looking SF like 2.34512% or something.
 

toxikon

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I tend to finagle my recipe on soapcalc to where my oils are all integers in ounces and then I use grams for the lye. I have been known to finagle my recipe to where everything is in integers... and that usually means I have a weird looking SF like 2.34512% or something.
It would be cool if lye calculators had an option you could choose to round numbers at the cost of small changes to SF or oil amount! I'd definitely make use of that.
 

kchaystack

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It would be cool if lye calculators had an option you could choose to round numbers at the cost of small changes to SF or oil amount! I'd definitely make use of that.
Rounding like that is fine if you are using grams, but if you are using ounces and your batch size is just a pound or two, that can be a big change.
 

toxikon

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Rounding like that is fine if you are using grams, but if you are using ounces and your batch size is just a pound or two, that can be a big change.
Oh definitely! Grams would be the much better unit.
 

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