Sand as a heat regulator for cavity molds?

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Has anyone ever tried pushing a mold, the kind with six individual cavities, into a bed of sand that would act as a more constant, even heat source or insulator around individual cavities? Just wondering if it would be more like making soap in a loaf mold where the mass of the batter seems to increase or sustain the rate of saponification. If what happens in the loaf is not due to the mass of batter and heat retention, then the sand probably wouldn’t help, but if heat retention is important, then the sand bed idea might work. A side benefit would be that my flower molds would have less tendency to tip (due to the flexibility of the silicone), which they always seem to do no matter how careful I am. I would probably want to put plastic wrap between the sand and the mold in order to keep the mold clean and the sand out of my soap. I realize that I could put the mold on a heating pad, but somehow I have the idea that the effect would be different.

I have no problem with anyone telling me why this is a crazy idea.
 
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How are you thinking of heating the sand?
Seems 'extra' but it definitely has a sort of rustic appeal.

Just saw your other thread, aha. Yes, try it and takes photos. One way or another it sounds like fun! Soap and sand! I sense a new trend on the horizon :)
 
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How are you thinking of heating the sand?
I would heat the sand in the oven. This idea started with being annoyed about my molds tipping, which led me to thinking about oysters on the half shell tipping. The solution for that is a bed of crushed ice if we want them cold, or rock salt if we want to cook them. Then my brain went to keeping soap warm on a bed of rock salt and from there to a bed of sand. Due to the small grain size and packing, I think the sand would be a better thermal mass = more even temperatures around the individual cavities. I tried to gel my cavity molds on a heating pad last night and that went nowhere. I can force gel in the oven, but it’s a lot of work to keep the temperature of my oven in the right temperature range.
 
Sounds good! I think oven temps fluctuate a lot so it might be easier for you to be precise with the sand. Can chart the heat loss :) How much sand do you think you'll need to maintain heat long enough for a full gel?

I'm going to have fun watching this experiment on the sidelines.
 
I would heat the sand in the oven. This idea started with being annoyed about my molds tipping, which led me to thinking about oysters on the half shell tipping. The solution for that is a bed of crushed ice if we want them cold, or rock salt if we want to cook them. Then my brain went to keeping soap warm on a bed of rock salt and from there to a bed of sand. Due to the small grain size and packing, I think the sand would be a better thermal mass = more even temperatures around the individual cavities. I tried to gel my cavity molds on a heating pad last night and that went nowhere. I can force gel in the oven, but it’s a lot of work to keep the temperature of my oven in the right temperature range.

A gal I follow in Taiwan use a styrofoam cooler to insulate her soaps. Not one of those $5.00 ones you get at Walmart, but studies and flatter. But you could probably use a $5.00 one to make cut-outs that you molds fit into.
 
I made a sand soap once!
Ok the competition is on. In how many ways can you involve sand in your soap? I'm thinking the water needs a little extra filtration.... through sand :swinging:

I think of cavity mold soapers as different from loaf soapers, the way CP and HP soapers are different. Are there any special tricks that go into cavity mold soaping other than extra heat? I keep thinking a little extra water would help, but maybe that is already a thing.

@KiwiMoose How does the sand soap feel? Is it just for feet?
 
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I think of cavity mold soapers as different from loaf soapers, the way CP and HP soapers are different. Are there any special tricks that go into cavity mold soaping other than extra heat? I keep thinking a little extra water would help, but maybe that is already a thing.

@KiwiMoose How does the sand soap feel? Is it just for feet?
It's a very fine black sand, from the west coast of New Zealand. It's gritty but much less so that fine ground pumice. A good hand soap. It's supposed to mimic sand, sea and surf:

IMG_2600.jpeg
Sorry for thread hijack @Mobjack Bay - as a consolation I'll add a 'brown' pic to your other thread. :)
 
When I went to summer camp as a child, rumor had it that the punishment for breaking a rule was getting washed in the shower with a bar of soap that had been coated with sand. So far I haven’t added any sand to my soap :).

@TheGecko I thought about putting the bed of sand into the bottom of a cooler. That would help even more with heat retention.
 
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In Pakistan there is a method of brewing coffee where a bed of sand is heated from below and the brewer pushes a metal cup of water and grounds into the sand to heat it. In bet you could easily adapt to this method with some type of heating plate and a pan of sand!
 
I wonder if there is something you could mix with the sand to make it stiff? That way you only have to set up the sand bed one time.

Maybe a little plaster, just enough to set the sand in place without making it super hard.

Not sure if it would hold up to a oven though but a heating pad should work.
 
I filled a couple of large ziploc bags with rice, set them in a cardboard box, set my empty molds on top and heated everything to 120F while I made my batter. When it came time to pour the the batter, everything was warm, which means the batter did not have a chance to cool down from where it was when I finished pouring. I put everything back in the pre-warmed (160F) and then turned the oven down as low as it goes, about 110F. I have the timer set for 30 min...

The plastic bags are not especially pliable and it will probably work better to set the molds directly into the rice.

Another thing I did for the first time today was cover the molds with parchment paper. It’s touching the individual bars, so I hope nothing weird and unanticipated happens.
 
I’m not sure. In my experience with sand, I haven’t found it to be particularly good at retaining heat. It’s not a fluid really, just many many tiny solids, each with more surface area relative to mass. Probably some sort of very dense/viscous liquid would be better? But messier...

sand is *amazing* for soundproofing, though. Kills vibrations dead. Your soap will be very, very quiet in the mold!
 
I’m not sure. In my experience with sand, I haven’t found it to be particularly good at retaining heat. It’s not a fluid really, just many many tiny solids, each with more surface area relative to mass. Probably some sort of very dense/viscous liquid would be better? But messier...

sand is *amazing* for soundproofing, though. Kills vibrations dead. Your soap will be very, very quiet in the mold!
Water would be the best, but until I figure out how to contain it, I’m sticking with something solid. I don’t need the solid to do the entire job, I just need it to act like a big batch of soap in a mold.
 
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