When do I unmold soap?

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Viore

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I've made about 10 batches of soap, and most of them have stuck to the mold when I tried to unmold after 24 hours. The top of the soap feels firm to me. How do I know the soap is ready to come out?

I usually use a HDPE plastic mold that doesn't require a liner, but I'm thinking I should line all my molds if the soap is going to stick to it. I also put the soap into a freezer for an hour or two before unmolding to make it harder.
 

zolveria

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Depend on your RECIPE.. I un mold mine the next morning. I normally cook batches after dinner and un mold in the morning. I also use Sodium Lactate to make them harder. I have how ever found that when i use HDPE it has stuck so i simply place in the freezer for a little while and they un mold. I hardly use that mold. but it works for my Soleseife soaps. ( Sea Salt Soap) I use wood and line it with oven liner or freezer paper. Silicone Liner are the best also
I've made about 10 batches of soap, and most of them have stuck to the mold when I tried to unmold after 24 hours. The top of the soap feels firm to me. How do I know the soap is ready to come out?

I usually use a HDPE plastic mold that doesn't require a liner, but I'm thinking I should line all my molds if the soap is going to stick to it. I also put the soap into a freezer for an hour or two before unmolding to make it harder.
 

galaxyMLP

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You pretty much have to line all molds (even no line ones) for CP soap. It's very sticky stuff! I got some no line molds on etsy and I line all sides/bottom for CP and the 2 long sides/bottom for HP soap. It's unfortunate, I know, but it really is necessary.
 
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Obsidian

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HDPE are known for sticking even though they are supposed to be liner free. Try lining your mold or greasing it with a very thin layer of petroleum jelly.
 

commoncenz

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I've never used an HDPE mold. However, I have a friend who uses them. He lines them with Mineral Oil and doesn't seem to have any problems. As with the Petroleum Jelly that Obsidian noted, I'd assume that you would not want to use too much mineral oil; just a thin coating.
 

cmzaha

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You should line your hdpe with freezer paper. I know some say it is not necessary but I only use hdpe molds and have to line them. The other alternative is to use Vaseline as a mold release, but I find it just to messy
 

IrishLass

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I don't have HDPE molds, but I do have one wooden mold that has HDPE liners (Brambleberry's wooden vertical mold), and to be perfectly honest, I absolutely hate, hate, hate those liners- sticky-wickets and ruiners of soap are what they are no matter what kind of trick I use to outsmart them, dagnabit! :twisted: Having said that, though, I do actually love the mold itself, and so I have taken to lining it with other things that allow me to be able to unmold my soap much easier and in one piece.


IrishLass :)
 

navigator9

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Gel/non gel is also a factor in unmolding. I use only silicone molds, and when I gel, I unmold the following morning, with no problems. But if I don't gel, I have to wait several days to a week to unmold cleanly. Don't know how that translates to HDPE molds, but that's my experience with silicone.
 

shunt2011

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Another vote for lining those. I have one (Kelsei Mold) and soap just sticks to it. Now I only use it for salt bars and those come out a bit easier but I line the bottom and then grease the sides and dividers with mineral oil and that helps slide them out. I use silicone exclusively for everything else.
 

kumudini

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I have HDPE molds and I line them with parchment, bottom and two long sides. I had mine custom made to make soap that would fit in my small hand. I had talked to the seller and he so willingly shared many tips about working with these kind of molds. The explanation he gave for the lining requirement was that: the CP soap, being a liquid when poured, creates a vacuum seal between itself and the mold, kind of like a wet plate on a glass table. And it won't release no matter the number of days in the fridge.The lining would prevent that seal forming. He advised to thoroughly wet the inside of the mold, put your pre-cut parchment in and crease it into the long corners with your nail. It takes few seconds for me to do that.
No need to line for HP soap.
Recently I got a clear plastic shelf liner from Costco, I'm going to cut that to size and use that and hopefully reuse it several times.
 

cmzaha

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I don't have HDPE molds, but I do have one wooden mold that has HDPE liners (Brambleberry's wooden vertical mold), and to be perfectly honest, I absolutely hate, hate, hate those liners- sticky-wickets and ruiners of soap are what they are no matter what kind of trick I use to outsmart them, dagnabit! :twisted: Having said that, though, I do actually love the mold itself, and so I have taken to lining it with other things that allow me to be able to unmold my soap much easier and in one piece.


IrishLass :)
Always wondered why they though hdpe liners would release soap
 

cmzaha

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I have HDPE molds and I line them with parchment, bottom and two long sides. I had mine custom made to make soap that would fit in my small hand. I had talked to the seller and he so willingly shared many tips about working with these kind of molds. The explanation he gave for the lining requirement was that: the CP soap, being a liquid when poured, creates a vacuum seal between itself and the mold, kind of like a wet plate on a glass table. And it won't release no matter the number of days in the fridge.The lining would prevent that seal forming. He advised to thoroughly wet the inside of the mold, put your pre-cut parchment in and crease it into the long corners with your nail. It takes few seconds for me to do that.
No need to line for HP soap.
Recently I got a clear plastic shelf liner from Costco, I'm going to cut that to size and use that and hopefully reuse it several times.
Really does not matter why the soap sticks, soap sticks. You can actually line a hdpe with 1 cut of paper, vaseline or mineral oil the short ends, then cut a slip sheet the will go down one side across the bottom and up the other side, for mine I cut my paper 9.5# and the paper fits perfectly in my 18" mold. I do cut a piece for each end since I hate gooey molds using vaseline. Easy Peasy. One other way is to let the soap stay in the mold a month or so and wait for it to start shrinking away from the sides, but then who has time or patience for that. Not me!
 

kumudini

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Carolyn, I agree, the CP soap sticks no matter why. I was just putting my 2 cents in as to the why:), as it doesn't really make sense why a supposedly non stick surface like HDPE sticks like it's nobody's business. I do use a single cut of parchment and never bother to line the short sides. They release fine for me. Never used any other stuff to line my molds either.
I would need my molds well before the month or two, even if I had the patience to wait.
 

spenny92

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I use silicone moulds and don't normally have problems with unmoulding, they just pop out nicely the next morning!
 

cmzaha

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Carolyn, I agree, the CP soap sticks no matter why. I was just putting my 2 cents in as to the why:), as it doesn't really make sense why a supposedly non stick surface like HDPE sticks like it's nobody's business. I do use a single cut of parchment and never bother to line the short sides. They release fine for me. Never used any other stuff to line my molds either.
I would need my molds well before the month or two, even if I had the patience to wait.
I have a couple of very small 1.5 lb hdpe molds that are the smooth hdpe and it still loves to stick! My larger hdpe are not smooth so smooth or not does not seem to matter. Sometimes I do not line the ends but then have to take a knife to separate it from the ends. I also find hp does not give me the stick problems
 

Viore

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Thank you all for your input! Looks like I'll be learning how to line these molds then.

I still don't know what soap looks / feels like when it's ready to unmold. Does it separate from the sides of the mold? I know salt soaps are ready to unmold in a matter of hours, but how do you know it's ready?
 

The Efficacious Gentleman

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You get used to your recipes after a few times. But before then, I poke it with a knife to see how firm it is and then maybe take the loaf out of the mould in the paper liner to air a while. Keeping an eye on it, poking with the knife until it can safely be cut
 

Seawolfe

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The nice thing about lining your mold with paper is that you can lift it out and evaluate if its ready to be unpeeled from the paper and if its solid enough to cut. I think lining with butcher or parchment paper gives you more chances to get the timing right.
 

cmzaha

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As SeaWolfe mentioned with heavier paper such as coated butcher you can gently lift from the mold and check the sides. I usually let mine stay overnight and remove the next morning pull the liner from the sides and let it sit another day befor cutting unless it feels very hard. You will eventually know your recipes. I have one recipe that is so hard I have to unmold and cut within 6 hrs.
 
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