Density of soap?

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dxw

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I am new to all this, but enjoying immensely ... as long as I don't dwell too long over this morning's effort.

Anyways, I do not have any of those nice silicone moulds yet and bash some timber scraps together, and throw in some baking paper, to make my soap moulds. I need to make a mould for the batch I'm hoping to prepare (rebatch) later today.

It weighs 1.75kg, so what volume should I be looking at if I want to use the one mould? Given the fatty / oily derivation of soap I am assuming it's density is <1 ... but how much? I guess I could just make my mould able to hold 2l or 2.5l to cover my options.

btw, these moulds are very temporary and slap-dash so they do not need to be exactly-anything.
 
A mold 12-14" (30-36 cm) long on the inside should be able to hold almost 4 pounds of soap (your 1.75 kilos), if the other dimensions are pretty close to 'standard' (9 cm by 6 cm for height/width) for a loaf mold. I'd err on the side of making it longer.
 
A mold 12-14" (30-36 cm) long on the inside should be able to hold almost 4 pounds of soap (your 1.75 kilos), if the other dimensions are pretty close to 'standard' (9 cm by 6 cm for height/width) for a loaf mold. I'd err on the side of making it longer.

Brilliant, thanks you very much. I've thrown together some timber and clamps to make 6cm (variable) x up-to-10cm x 40cm which will hopefully let me make 6 x 9 x 40 (ish). Fingers crossed.

I don't know if this will help, but you might see if my mold size calculator would be helpful. See here: https://goo.gl/CPmpsh

Thanks DeeAnna. That *is* going to be useful in the future, but it seems to start a bit early in the process for my present problem.

Those dimensions were perfect, thanks.

soap mould.jpg
 
Awesome! How'd the rebatch turn out?

Ummm, I learned that you could burn soap :)

It was very effort intensive, and I was not prepared for the gloopy consistency. I suspect I added too much liquid in the endstill in the mould and I'll see how that goes tomorrow.

It does smell lovely though, and I did get to play with some colourants.

Awesome! How'd the rebatch turn out?

I just cut my rebatch handmill effort, so will report here and seek thoughts.

It started out as my first-ever soap effort, a 70% olive 25% coconut oil CP with some other oils and a little (?2% superfatting). I used no colours and rosewater as a scent. I did not know that rosewater was not great for soap scenting, and my batch turned out a slightly greeninsh yellow and smelling only of olive oil. That smell faded over the following week but I decided to use it to try handmilling, and dabble with other scents and with micas.

I grated the batch, saving two bars to see how they progress with curing time, and left it until last weekend. I made up four batches of scent / colour: 1. peach and some titanium oxide; 2. peach and orange-peach colour; 3. peach and pink-peach colour; and 4. coconut/vanilla and titanium. I used peach kernel oil for the frangrance/colour batches.
I used milk as my main liquid and an oven-based method for rebatching.

It would not melt at all nicely and I added more liquid. I also increased the temperature (140C) and managed to caramelise some of it. Finally I got it to a semiliquid (gelatinous yellow petroleum jelly) consistency and divided it 80%/20% popping the 20% back into the oven to keep pliable. I mixed #1 scent colour throughout, and then sort of swirled #2 and #3 roughly through the mix. I then spooned it, quite messily, into my homemade wooden mould and bonked it on the bench a little to try and smooth out the larger mountains. With the 20% I added the colour/dye and spooned-smoothed it as a layer on top of the main peach mix.

The next day the mixture in the mould still felt semiliquid. I left it for another couple of days, and it was still very soft so I popped it (mould and all) into the fridge. After two days there, this morning, it felt soft but firm so I removed the paper-clad block from the mould, inspected, and cut.

It had a very 'moist' oily exterior surface and there was obvious colour mica swirled over the surface. The mica was loose and transferred onto my fingers when I touched the soap. The block cut easily, still relatively soft, but some small white blobules dragged as the knife cut through the block. I assume they were little collections of the titanium oxide colourant.

It does smell great and the colours are a base of pale cream-brown with the pink and orange forming swirl patterns, there is nothing to suggest white / cream colours yet.

Anyways, here's a couple of photos. I suspect, subject to your advice, that:
1. I used way too much liquid in my rebatching effort;
2. I impatiently burnt part of the mix;
3. Perhaps I mixed the micas in an inappropriate carrier (oil);
4. Perhaps I should have mixed the orange and pink mica liquids into a small aliquot of soap before adding it to the main batter ... maybe that would have 'embedded' the colour better into the mix;
5. Perhaps I used way too little titanium oxide ... but I guess that part may lighten over time.

First image is the uncut block, and the second is some of the cut bars (about 20% of the entire batch).

2018 01 27 remilled peach block.jpg


2018 01 27 remilled peach cut bars.jpg
 
I just cut my rebatch handmill effort, so will report here and seek thoughts.

It started out as my first-ever soap effort, a 70% olive 25% coconut oil CP with some other oils and a little (?2% superfatting). I used no colours and rosewater as a scent. I did not know that rosewater was not great for soap scenting, and my batch turned out a slightly greeninsh yellow and smelling only of olive oil. That smell faded over the following week but I decided to use it to try handmilling, and dabble with other scents and with micas.

I grated the batch, saving two bars to see how they progress with curing time, and left it until last weekend. I made up four batches of scent / colour: 1. peach and some titanium oxide; 2. peach and orange-peach colour; 3. peach and pink-peach colour; and 4. coconut/vanilla and titanium. I used peach kernel oil for the frangrance/colour batches.
I used milk as my main liquid and an oven-based method for rebatching.

It would not melt at all nicely and I added more liquid. I also increased the temperature (140C) and managed to caramelise some of it. Finally I got it to a semiliquid (gelatinous yellow petroleum jelly) consistency and divided it 80%/20% popping the 20% back into the oven to keep pliable. I mixed #1 scent colour throughout, and then sort of swirled #2 and #3 roughly through the mix. I then spooned it, quite messily, into my homemade wooden mould and bonked it on the bench a little to try and smooth out the larger mountains. With the 20% I added the colour/dye and spooned-smoothed it as a layer on top of the main peach mix.

The next day the mixture in the mould still felt semiliquid. I left it for another couple of days, and it was still very soft so I popped it (mould and all) into the fridge. After two days there, this morning, it felt soft but firm so I removed the paper-clad block from the mould, inspected, and cut.

It had a very 'moist' oily exterior surface and there was obvious colour mica swirled over the surface. The mica was loose and transferred onto my fingers when I touched the soap. The block cut easily, still relatively soft, but some small white blobules dragged as the knife cut through the block. I assume they were little collections of the titanium oxide colourant.

It does smell great and the colours are a base of pale cream-brown with the pink and orange forming swirl patterns, there is nothing to suggest white / cream colours yet.

Anyways, here's a couple of photos. I suspect, subject to your advice, that:
1. I used way too much liquid in my rebatching effort;
2. I impatiently burnt part of the mix;
3. Perhaps I mixed the micas in an inappropriate carrier (oil);
4. Perhaps I should have mixed the orange and pink mica liquids into a small aliquot of soap before adding it to the main batter ... maybe that would have 'embedded' the colour better into the mix;
5. Perhaps I used way too little titanium oxide ... but I guess that part may lighten over time.

First image is the uncut block, and the second is some of the cut bars (about 20% of the entire batch).

They look nice.

A couple of questions:

Did you use Titanium Oxide or Titanium Dioxide? I am not familiar with TO but am with TD. Perhaps it's just a nomenclature error? Or do you actually have TO that you used in your soap? BTW, I have not noticed TD lightening any more over time than it was out of the mold.

Did you actually carmelize the soap? As in carmelized onions? I like carmelized onions, carmelized soap may be overcooked. But if you didn't smell burned soap, then maybe not an issue.

Did you use too much water? Well, that can happen. When it does, the soap takes FOREVER to dry out and it shrinks big time over that time of drying out. And it starts to look really sort of crinkly and ugly as it looses all that excess water. And if it was placed in a pretty mold with fancy design features they all disappear (the fancy design features) and you end up with an ugly blob of soap. But the soap is still soap, may still smell great and often bubbles and lathers beautifully. I know this because I did that once and learned my lesson about too much water in a re-batch.

Did you say you used vanilla? Vanillin containing fragrance oils are notorious for darkening soap and in fact the higher the content, the darker the soap becomes over time. I made a pretty Easter soap last year using only pastel colors that is now completely brown because of the DB FO I used. (It's all I had with me at the time and the entire project was just an experiment in a new-to-me technique, so discoloration wasn't a real concern, but it was a lesson.)

Yes, it is possible the micas weren't mixed well enough. That takes practice, I believe. As with any craft, the more you practice, the better you become at the craft.

So, I suggest leaving them on the curing rack for a GOOD LONG TIME, I mean months, not weeks, months and watch what happens. They are pretty to look at and if they smell nice, that's always a good thing. Maybe use one of them to see how it performs with use. But leave most of them to dry out and also to cure.
 
They look nice.

Thanks. They sort of did what I was trying, in a very first-try kind of way :)

A couple of questions:

Did you use Titanium Oxide or Titanium Dioxide?

Sorry, that was just me being not-so-familiar with the terms and lazily choosing a 'near enough' chemical. Wrong! I used TD.

BTW, I have not noticed TD lightening any more over time than it was out of the mold.

I was hoping the base soap might lighten, rather than the colourants.

Did you actually carmelize the soap? As in carmelized onions?

What happened seemed pretty much caramelization to me. a 5mm thick later, touching the edge of the container, turned a lovely rich darker brown colour when I turned the heat up a little. There were a few small black flecks on the pan itself, which I took to be small burned spots. I scraped the latter out and mixed the caramel into the rest of the batter ... and turned the temperature back down.

Did you use too much water? Well, that can happen. When it does, the soap takes FOREVER to dry out and it shrinks big time over that time of drying out. And it starts to look really sort of crinkly and ugly as it looses all that excess water. And if it was placed in a pretty mold with fancy design features they all disappear (the fancy design features) and you end up with an ugly blob of soap. But the soap is still soap, may still smell great and often bubbles and lathers beautifully. I know this because I did that once and learned my lesson about too much water in a re-batch.

That's good news. I was hoping it'd be a matter of just letting it dry out over a prolonged time. I had not thought of the shrinkage and crinkling but that makes sense too.

Did you say you used vanilla?

I used a commercial coconut/vanilla/cream scent. I assume they're synthetic scents rather than essential oils. I'd already been told about vanillin, so was willing to accept that possibility here. Maybe I can claim the upper layer is pie-crust, brown, if it does not turn out to be cream :)


So, I suggest leaving them on the curing rack for a GOOD LONG TIME, I mean months, not weeks, months and watch what happens. They are pretty to look at and if they smell nice, that's always a good thing. Maybe use one of them to see how it performs with use. But leave most of them to dry out and also to cure.

Great, thanks. They have their own rack now and I will checkin on them periodically.

Now, by popular family demand, I am off to make another syndet shampoo bar batch. S'funny, I saw syndet as an interesting experimental aside but not really what I wanted to make - all natural soaps and associated products - yet the entire household wants more of that stuff. Oh well.
:confused:
 

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