Whether to fill silicone mold to the top or to leave some space

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alexanderte

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I recently bought a few 10″ × 3.625″ × 2.25″ silicone molds from Bramble Berry. What I wonder is if a silicone mold is supposed to be filled all the way to the top, or if I should leave some space.

What I like about the numbers 3.625 and 2.25 is that if you divide 3.625 with 2.25 then you get 1.61 which is approximately the golden ratio. I would loose this by filling it to e.g. 2″.

I tried to fill a mold to the top, and figured out the amount by oils by using the multiply by .4 trick mentioned in one of the pinned threads. This seemed to fill it to the edge, but I struggle with plastic wrap covering the top of the mold. In the middle of the mold it is touching the batter. Any trick to avoid this?
 
That is my downfall nearly every time. I muss up my swirls and decorations when I cover my soap with plastic. That's why I switched to my "shower caps" for the silicone molds. They're actually bowl covers and work well. I don't mess up as much. In answer to your question, every soaper has their own preference. You have to figure out what works best for you. I like to leave a little space at the top of mine, but I don't always manage to do that. Some people do "high tops" on their soaps, so they've got soap that comes up past the top of the rim. I have found that the easiest way for me to not mess up my top is to put a box over it instead of covering it with plastic. I'll spray it with alcohol (91%) and invert a box over it to maintain the heat. I usually put the mold on a towel and fluff the towel around the sides to help maintain the heat, as well.
 
A box works well. I lay a towel on top of a heating pad, place my mold on top of that, put the box over the mold and bring the ends of the towel up over the box. Alternately, you can put some inverted glasses or something taller than your mold around the mold and balance a piece of cardboard (or a book or something else flat) and put towels over that.
 
I use cardboard boxes. I always seem to have too many, so at least they get used for something... I just spritz the top liberally with alcohol, cover it with the box, and an old blanket. My molds are home made, so the height of my soap in the mold depends on the size batch I make. I do find it easier when my soap is a bit below the top edge.
 
I recently bought a few 10″ × 3.625″ × 2.25″ silicone molds from Bramble Berry. What I wonder is if a silicone mold is supposed to be filled all the way to the top, or if I should leave some space.

What I like about the numbers 3.625 and 2.25 is that if you divide 3.625 with 2.25 then you get 1.61 which is approximately the golden ratio. I would loose this by filling it to e.g. 2″.

I tried to fill a mold to the top, and figured out the amount by oils by using the multiply by .4 trick mentioned in one of the pinned threads. This seemed to fill it to the edge, but I struggle with plastic wrap covering the top of the mold. In the middle of the mold it is touching the batter. Any trick to avoid this?

Yes you can fill them all the way to the top. I don't bother covering my soaps but I spritz with alcohol to minimize ash.
 
I recently bought a few 10″ × 3.625″ × 2.25″ silicone molds from Bramble Berry. What I wonder is if a silicone mold is supposed to be filled all the way to the top, or if I should leave some space.

What I like about the numbers 3.625 and 2.25 is that if you divide 3.625 with 2.25 then you get 1.61 which is approximately the golden ratio. I would loose this by filling it to e.g. 2″.

I tried to fill a mold to the top, and figured out the amount by oils by using the multiply by .4 trick mentioned in one of the pinned threads. This seemed to fill it to the edge, but I struggle with plastic wrap covering the top of the mold. In the middle of the mold it is touching the batter. Any trick to avoid this?

BB's 10" mold is one of my most frequently used molds. My standard recipe for it is 36oz oils and 1.8:1 water:lye ratio. It'll fill it exactly to the top if my batter is thin or allow me to spoon up the top with a thicker batter. My method to keep the plastic wrap, towels, etc off the top is to use 1/2" sq dowel type pieces of wood that I run along the long side then place 12" x 5" cardboard over that (12' x 5" is the size of the outer rim of the mold). From there I can cover with towels and keep decorative tops looking good. If I'm doing several batches in a day then I line up the molds side by side and run the wood dowels along all the short ends, put on the cardboard pieces, cover with towels. I hope I explained that well enough! If not, let me know and I'll attach pics that show what I mean. :)
 
Thanks for the advice, all of you. Can I use a paper shoe box, e.g. those that Adidas use?
BB's 10" mold is one of my most frequently used molds. My standard recipe for it is 36oz oils and 1.8:1 water:lye ratio. It'll fill it exactly to the top if my batter is thin or allow me to spoon up the top with a thicker batter. My method to keep the plastic wrap, towels, etc off the top is to use 1/2" sq dowel type pieces of wood that I run along the long side then place 12" x 5" cardboard over that (12' x 5" is the size of the outer rim of the mold). From there I can cover with towels and keep decorative tops looking good. If I'm doing several batches in a day then I line up the molds side by side and run the wood dowels along all the short ends, put on the cardboard pieces, cover with towels. I hope I explained that well enough! If not, let me know and I'll attach pics that show what I mean. :)
Thanks! I think I get it. I’ll post a picture in this thread when I’ve found something to use that resembles your solution.
 
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Cardboard shoe boxes work fine. Just as long as they are large enough. I used to use those, until my hubby tossed my perfectly trimmed down one by accident. Then I swapped to a plastic one that gives me about an inch of clearance over the top of the mold. It fits perfectly. All you need is some way to keep the box/towel/blanket/etc off the soap. Plastic wrap is such a pill to use.
 
Cardboard shoe boxes work fine. Just as long as they are large enough. I used to use those, until my hubby tossed my perfectly trimmed down one by accident. Then I swapped to a plastic one that gives me about an inch of clearance over the top of the mold. It fits perfectly. All you need is some way to keep the box/towel/blanket/etc off the soap. Plastic wrap is such a pill to use.
Plastic wrap is the worst.
 
Since I am always getting cardboard boxes and trying to find uses for them before recycling, I find that inverted cardboard boxes are the perfect cover for my molds. Depending on which molds I am using, I have different boxes I can use. I have also cut some down to use as 'lids' to fit some of my molds for when they go into the oven for CPOP. Covering with a towel or wool blanket in addition to the box-top depends on how warm it is and the type of batter. I do prefer my soap to gel, so I do usually insulate, but sometimes not.

Filling all the way to the top of the mold is something I like to do so that I can smooth the top for a flat surface. Even when I use the standard method for calculating how much oils I need for a particular mold, I often end up with too much (easy as I have several small individual molds for the extra batter) or not enough. When I end up with not enough (higher lye concentration is usually the reason, I suppose), then obviously I don't fill all the way to the top and I don't get the smooth surface I prefer.

Before filling my molds, I like to put them into a sturdy leak-proof and heat-safe carrying tray where they will sit throughout the gel phase. That way when I carry it if anything spills over on my way to the spot they will gel (upstairs in another room or the oven for CPOP) then it spills onto the tray. Also if the batter overheats or volcanoes, it will spill over onto the tray and not ruin the surrounding surface. I don't like messes in my oven, something I learned from cooking (I do the same thing when I cook, keep a tray under all casserole dishes, for example.) And I unfortunately stained the bedspread of the bed where I have soaps in cardboard 'trays' drying out, because I had not used a leak proof tray at the time and oils oozed out on the bedspread. Ever since then, I now cover every surface before every putting any soaps atop, even when I don't expect them to ooze oils, which of course why would I expect that?
 
Above advice all excellent! I, prefer to gel my soaps. I put them in an "igloo", which is a heavy duty plastic cooler. This way, I can gel my soaps, and not worry about them. I also spray the tops with 91% alcohol to help avoid ash. Welcome to the wonderful world of soap making! I personally am truly grateful for all the help and support here. Happy soaping!
 
I modified the box that my molds were delivered in. I could trim the height, but chose instead to build something to place the mold on top of as I don’t have a proper scissor. Because I couldn’t modify the size of the box, I chose to add bubble wrap to each of the sides. Let’s see how this will work out. :)

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Is there a problem having space at the top of the mold? If the batter is liquid enough to settle down to the bottom, what difference does it make if there is an inch or so of space at the top the mold?
 
I think I must be the only person who loves the plastic cling wrap and never have a problem with it messing up my fancy tops. I spray with alcohol, cover with plastic wrap, then either put a box over the top and cover with a towel, or if it's a known heater (either ingredients or fragrance) I leave the box and towel off but still cover with plastic wrap.
 
I think I must be the only person who loves the plastic cling wrap and never have a problem with it messing up my fancy tops. I spray with alcohol, cover with plastic wrap, then either put a box over the top and cover with a towel, or if it's a known heater (either ingredients or fragrance) I leave the box and towel off but still cover with plastic wrap.

No, you are not the only one. I don't have any problem with plastic wrap either. I use it the same as you (except that I don't do fancy tops), and sometimes I used it as a barrier between my gloved hands and the soap to create a smoother surface on a thicker soap.
 
No, you are not the only one. I don't have any problem with plastic wrap either. I use it the same as you (except that I don't do fancy tops), and sometimes I used it as a barrier between my gloved hands and the soap to create a smoother surface on a thicker soap.

Almost everyone of my soaps has a fancy top, swirls of some sort or high peaks (not piped, just 'fluffed up' so to speak) and the only time I have problems is if it overheats and the tops fall, but that's not due to the plastic wrap.
 
Before I stopped covering my soap, I bought some large plastic placemats. They were intended for outdoor patio use but I cut them in strips that fit the top of my mold. This only worked for soap that had head room in the mold. Now that I use sodium lactate and a 35% lye solution and don't gel, I don't cover and get less ash.
 
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