Should I make a 500ml mold

[chibi-soap]

Hi Lovely Soapers,

last week I made my first soap (yay!) using a 1 litre milk carton. This week I'm thinking of making a mold out of the that corrugated plastic stuff they use for signs.

[ame]https://www.youtube.com/watch?v=avzZUyF5o5I[/ame]

But ... I have all these ideas for soap running about in my head, and I want to make lots of different types and explore their properties in the shower. I expect there's a limit to how many my friends will take, so is there any disadvantage to a 500ml (1 US pint) mold, which would make 5 bars of 2.5cm/1 inch soap?

 

[BattleGnome]

I have a 4" square mold that holds roughly one pound of soap. That will make four bars which is perfect if I want to test an ingredient or scent but am not sure I want to gift them. Mentally I'm having some issues visualizing a pint right now but based on a pint of berries it should be similar.

So short answer, yes. A pint should be fine. As a reference point, I got my mold from Brambleberry and the exact dimensions should be on their website if you want numbers to compare.

 

[Susie]

No disadvantage at all. You would just have to change the size on the soap calculator.

 

[CaraBou]

Good idea to make a small mold like that, assuming you want to soap a lot, try a lot of new things, or don't get very dirty . It is way more economical for ingredients.

I almost exclusively use my 1 pound mold (400 - 450 g of oils) even though I have a closet full of molds. I'm always messing around with color and trying new fragrances, which means sometimes I get results that I don't even want to give away!

I've never used that kind of plastic but it sure looks worth a try.

ETA: Here's the one I use. Durable, not very expensive, and super easy to unmold. Something to consider if/when you decide you're in for the long haul and don't want to mess with making your own.
http://www.wholesalesuppliesplus.com/products/small-loaf-silicone-mold.aspx

 

[The Efficacious Gentleman]

I have a 500g mould - it is great for when I want to try something out

 

[chibi-soap]

Thanks everyone. 500ml it is. Well... maybe 470ml + 2.5cm clearance at the top, which is about 700ml. Anyway, it will make about a pint of soap.

 

[Dahila]

well you should try 800 g one from Soaper crafters, Mine silicone is like 5 years old no wear at all with 500 g ; I mean weight not volume, we do not use volume in soap making. With 800 g you get 8 soaps and the amount is enough to see the difference in soaps. 500 g would not be enough for me to see the difference, especially if you add a bit of color or clay

 

[GreenAcreHomestead]

I'll speak to the mold material to be different.

That's a neat idea using the sign board, but it's not too cheap in my area--at least not that I have found yet (finding it free negates this argument). It's an awesome idea for small batches and test loafs, for sure, but I wouldn't want to trust it for a large batch like the video shows on one of them. I'm more comfortable with plywood for mold making, but that's just me. I understand not everyone is.

 

[penelopejane]

I tried using the corrugated stuff as a divider and I wasn't too impressed as it bent. I can't see how the person in the video managed to make a mold that size and keep it so perfect without bowing out unless she used it to line a wooden mold.

 

[CaraBou]

well you should try 800 g one from Soaper crafters, Mine silicone is like 5 years old no wear at all with 500 g ; I mean weight not volume, we do not use volume in soap making. With 800 g you get 8 soaps and the amount is enough to see the difference in soaps. 500 g would not be enough for me to see the difference, especially if you add a bit of color or clay

I don't understand what you're saying. Why do you need 8 bars to see a difference between batches?

 

[Dahila]

with 500 g is easy to make mistake with 700-800 g you make not only nice soap but also the amount of additives is not so small, it seams logical to me but I may be wrong

 

[The Efficacious Gentleman]

Additives should always be added relative to the batch size - so per bar the amount should be the same if you make a 500g batch or a 10,000g batch

 

[Gerry]

with 500 g is easy to make mistake with 700-800 g you make not only nice soap but also the amount of additives is not so small, it seams logical to me but I may be wrong

Yup, the margin of error is twice as great making 500 g as it is making a 1000 g batch, and that would matter most weighing out small things like EO/FO. If 18 g of EO is called for but your scale is only accurate to 2 g, you could be adding a little more than 10% too much or over 11% too little. This probably doesn't matter a heck of a lot because it's just fragrance. High accuracy (to a point of course) doesn't matter much in soap making. You can be 2 g off with most ingredients with a 500 g batch and in the scheme of things it doesn't matter so much.

Now I have other hobbies that require much more accuracy. That scale is not used for soap making.

 

[Dahila]

Gerry 2 grams ie Activated charcoal will make a lot of difference, it will make not only drying bar of soap but grey lather which I hate,

 

[The Efficacious Gentleman]

Well of course, any size mould is too small if the scale and/or your ability to use it is not up to it.

 

[Gerry]

Gerry 2 grams ie Activated charcoal will make a lot of difference, it will make not only drying bar of soap but grey lather which I hate,

You weigh out your activated charcoal when making a batch? 2 grams of AC is a huge amount of AC. It's very light stuff! I'd think you'd get black lather... not grey. :mrgreen:

I just add a premixed amount of AC until I get the shade I'm looking for. I've never weighed out any colourants for a batch of soap. I've used teaspoons sometimes...

And what's wrong with grey lather? It means the AC is working! Hahaha

 

[Dahila]

You weigh out your activated charcoal when making a batch? 2 grams of AC is a huge amount of AC. It's very light stuff! I'd think you'd get black lather... not grey. :mrgreen:

I just add a premixed amount of AC until I get the shade I'm looking for. I've never weighed out any colourants for a batch of soap. I've used teaspoons sometimes...

And what's wrong with grey lather? It means the AC is working! Hahaha

I do the same, just tsp but I start from small amount mix then add, AC is the easiest for me, I made so many of them, I think 1 tsp weight less than 0.5 g

 

[chibi-soap]

I have some cute little scales that weigh to 2 dec. places. I just used them for measuring 8.8g of milk powder.

One problem I just found with the smaller batch is the lye water cools down faster. Its quite cool here at the moment even though it's summer. In winter, that might be more of a problem.