UK measurements, US lye calculator?

[stationdragon]

Does using a lye calculator such as soapcalc and then using UK measurements make any difference?
I'm sorry if there's a really obvious answer to this but I'm terrible with numbers.
My batches have all failed despite very careful attention to EVERYTHING and I'm trying to eliminate possible problems to reach the source of all the failure.
Thanks

 

[Hazel]

Isn't the UK on the metric system? You can enter everything as grams. Also, the recipe section which you print off will show the amounts in pounds, ounces and grams. So if you're entering a recipe in ounces, it will still give you the weights in grams.

Can you post a sample recipe so I can see what you're doing?

 

[stationdragon]

yes we're on the metric system but I am just curious is a UK g, oz, lb is different to US because I'm losing my patience with these failed recipes. A lot of money is going down the drain despite my perfectionism and very, very, very careful weighing out of the ingredients.
I choose to use grams because it's the smallest possible increment giving me a greater deal of accuracy than oz's.
The recipe came out in points of grams e.g. 408.137g but my scales only measure in whole grams so I rounded them up. But being grams (which is a pretty small measurement) I assume that these points don't make a whole lot of difference.
I was given the choice of 76deg, 92deg or fractionated coconut oil on soapcalc. I looked at my jars and they only said 100% pure coconut oil, so unsure I entered fractionated. Perhaps this was a mistake?

 

[majstor]

I dont think theres difference between UK and US pounds or ounces, thats a standard weight. There are differences in fluid ounces, pints or cups but thats not issue here.

 

[VanessaP]

I was given the choice of 76deg, 92deg or fractionated coconut oil on soapcalc. I looked at my jars and they only said 100% pure coconut oil, so unsure I entered fractionated. Perhaps this was a mistake?

Generally, here in the US at least, you can't buy fractionated coconut oil in most stores. Assuming that your coconut oil was solid at room temp, it was most likely 76 deg which is what I find in our grocery stores. Fractionated coconut is the liquid form and usually used for massage oil. I have used fractionated up to 15% in CP though and it seems to be fine. I wouldn't use more than 20% unless you can compensate with it in other ways.

 

[stationdragon]

oh dear, well mine was solid at room temperature. Is this likely the offender here? It's definitely a measurements/sap value issue because of failed zap tests and lye crystals

 

[VanessaP]

Most likely it was then, yes. I just did a quick 100% coconut oil recipe on SoapCalc for a 1 pound batch, and it was .75 oz more lye needed for the fractionated.

 

[stationdragon]

yeah I've just done the same and found that the two temperature based ingredients come out exactly the same but the sap value of the fractionated is as you said, of significant value.
Right then, next experiment shall take place tomorrow and the failures shall be put to one side for a future rebatch.
Thanks for your insight x

 

[Hazel]

Travis,

If you'd like to post your recipe, I'll check it and we can compare the recommended amounts of lye.

 

[Fragola]

Speaking of unit's, it wouldn't matter even if they were different.

Mixing 20 grams of lye with 100 grams of oil will give you the same soap as mixing 20 oz lye with 100 oz oil. No matter if the oz are UK, US or Madagascar ounces.

 

[judymoody]

The coconut oil is probably the culprit. I went to soap calc and compared - 500 grams of 76 degree coconut oil requires 87 grams of lye. Fractionated requires 110 grams! (assuming 5% superfat default) That's a significant difference!

Hope your next batch goes well.

 

[stationdragon]

Ok thank you for pointing that out about the measurements. I had already considered that but taking into account my uneae with numbers I thought I'd better check with a wider audience. I do feel silly now.
I'm really quite sure that the issue here is that I hastily chose fractionated coconut oil which has a very different SAP value than solid. As I was using a 3lb recipe then this turned out to be about 30g out.
But for your own personal sleuthing here is the recipe;

408g coconut oil
885g olive oil (pomace)
68g Sweet almond oil

517g water
211g lye (here is the mistake as I used solid coconut oil but entered fractionated, giving me this answer when in fact it should be 192.5g)

This at a 5% superfat

 

[stationdragon]

PS girls -

I will win this mighty battle of the soaps and I shall perfect my recipe, produce a fantastic range of soaps (and more) and I shall be victorious (but only if you girls help me first haha, apparently we men really are rubbish...)

Cheers for all the input, you have no idea how appreciated it all is.

Kisses all round xx

 

[Hazel]

There's no need to feel silly. Everyone started out the same and lye calculators can be confusing when you first start working with them. I put your recipe in soapcalc and came up with 194 g lye which is still off from the amount you used.

You could rebatch this soap and add more oil to it so it won't be lye heavy. I think the best explanation I read about rebatching is by pure&simple. You'll have to scroll down and read her posts because she elaborates on how she does it as people asked her questions. Here's the link to the discussion.

http://soapmakingforum.com/forum/viewtopic.php?t=28489

I'm not great with numbers either but I'll try to help you figure out the amount of oils and lye you'll need to add for the rebatch. I'm going to do some calculating and get back with you in a little while.

 

[stationdragon]

Thanks for helping me look into this. The reason it would have showed a different amount is because I rounded the numbers off.

I entered these values into soap calc.

3lb oils
1oz per lb of fragrance
38% water
5% superfat

30% coconut oil
65% olive oil
5% sweet almond oil

This should give you the same value of lye as I had.
I rounded the numbers off because my scales are as small as grams but no less and soapcalc gives to 3 decimal places. I assume this makes little difference in soap making and without the decimals available on most kitchen or postal scales all we can do is round off.

Anyway, thanks for your interest x

 

[VanessaP]

A tip to make sure you don't round too much is to round your water up and your lye down.

189.6 g water can be 190g

174.8 g lye is better off being rounded back down to 174g to help prevent being lye heavy.

 

[Hazel]

Thanks for helping me look into this. The reason it would have showed a different amount is because I rounded the numbers off.

This should give you the same value of lye as I had.

I still get a different lye amount even with percentages. It's because I'm using a different lye calculator than you. This may be because lye calculators use slightly different SAP values.

Like VanessaP said, it's best to round your lye down. That's what I do with my recipes.

pure&simple recommends using 50/50 of old soap to the new oils. Do you have a double boiler? I think it might be easiest to do this in one. I took her explanation and tried to turn it into steps to follow. I think people use around 170 degrees F or 77 degrees C for the oven temperature. (Someone please correct me if I'm wrong!)

Grate soap & add it to the oil of the new batch
Place in oven to melt
Once the grated soap has melted enough, take out and stick blend to mix well
Add new lye solution
Cook for approximately 5-10 minutes – stirring occasionally
Add a little water if the consistency is too thick
Pour into mold

By the way, I forgot to tell you guys, once the consistency of the batch is satisfactory to you, pour it into the mold quick. It will harden very fast!

I may be wrong about this and you might want to wait until an experienced soaper gives an opinion but here’s my suggestion.

Use half of the old soap and add to the oils of your new batch.

New batch –

204 g coconut oil
443 g olive oil (pomace)
34 g Sweet almond oil

Since you needed 192 g lye, I would deduct 106 g (half of 211) from that amount and use 86 g lye for the new batch.

259 g water
86 g lye

This will probably give you higher than 5% SF but I don’t think it will be high enough to cause a problem. You’ll just have a little more oil that hasn’t saponified.

However, I'm just guessing this would work out. Hopefully an experienced soaper will come along and correct me if I'm wrong.