Silicone molds...bubbles!?

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jodym

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I am new to using silicone molds? is there a secret to getting bubbles out? I'm careful when I mix and pour... Thanx guys!

image.jpg
 
Do you CPOP your soap. I've heard some have issues with bubbles when CPOPing in silicone. I do sometimes but haven't had an issue. Also they could just be bubbles form the stick blender
 
ARGH. I wish I would have stumbled across this forum months ago. I, too, have had this problem with those flimsy flower molds you can by on Amazon. I did CPOP and kept thinking it was my soap formula - and kept changing the oils, etc. After combing through this forum, I see the problem resides in the molds themselves! So much time, ingredients wasted. Not to mention $.

Funny thing -- I don't have the same problem when I CPOP in my thick Brambleberry silicon molds. Just these cheap ones. There Brambleberry silicon molds do cause a little bubbling, but the cheap are just ridiculously full of bubbles. (I don't mind re the Brambleberry molds because I'm only making solid dish soap and shampoo bars. My first attempts at body soap in the flower molds was a disaster. I doubt HP would be any better result. And so...Look like for those cheap molds, CP is the way to go. (But I'm so impatient!)

Thanks Shunt2011 for your wisdom.
 
I cp in silicone molds without issues.

I place my silicone molds on cutting boards. Then fill the molds 3/4 full and then tap the molds on the ground to release any air bubbles before continuing. I finish filling the molds and tap again.

Perhaps, your trace is too thick? The only time I see bubbles in the soap made in individual silicone molds is if my fragrance was naughty and caused acceleration. The greater the acceleration, the greater the incidence of bubbles in the soap.
 
Thanks for chiming in. It was about as thick as a thin pudding - not too thick. The bubbles only happen when it's in the oven at 170. I'll try using the molds for CP next time.
Weird that I don't have the problem with the thicker Brambleberry molds.....
 
ARGH. I wish I would have stumbled across this forum months ago. I, too, have had this problem with those flimsy flower molds you can by on Amazon. I did CPOP and kept thinking it was my soap formula - and kept changing the oils, etc. After combing through this forum, I see the problem resides in the molds themselves! So much time, ingredients wasted. Not to mention $.

Funny thing -- I don't have the same problem when I CPOP in my thick Brambleberry silicon molds. Just these cheap ones. There Brambleberry silicon molds do cause a little bubbling, but the cheap are just ridiculously full of bubbles. (I don't mind re the Brambleberry molds because I'm only making solid dish soap and shampoo bars. My first attempts at body soap in the flower molds was a disaster. I doubt HP would be any better result. And so...Look like for those cheap molds, CP is the way to go. (But I'm so impatient!)

Thanks Shunt2011 for your wisdom.
What does impatience have to do with it? HP and CPOP still have to cure as long as CP so why not just cp your soap and not get the silicone rash?
 
From my understanding HP and CPOP do NOT have to cure as long as CP. That's what I've been reading for a long time. Would love to hear if others concur.
 
From my understanding HP and CPOP do NOT have to cure as long as CP. That's what I've been reading for a long time. Would love to hear if others concur.
No this is not right. cmzaha is right HP and CP soaps take the same amount of time to cure 4 - 6 weeks minimum.
To CPOP without getting bubbles heat the oven to 110*F and TURN IT OFF before putting wrapped soap in the oven. You will still have to cure for 4-6 weeks minimum but they should gel, be quicker to get out of the molds and the colours should be brighter.
Unfortunately, if you already get bubbles from the silicone you might have overheated the silicone beyond repair and bubbles will always form.
I have never done it, as I luckily learn how to CPOP properly on this forum, but I am pretty sure you can't see the damage to the molds until you soap with them as it appears on the soap not the molds.
 
From my understanding HP and CPOP do NOT have to cure as long as CP. That's what I've been reading for a long time. Would love to hear if others concur.

Your understanding is incorrect. Saponification and curing are two different animals. HP saponification is complete after cook and no zap. CP/CPOP saponification is done once no zap. Curing it separate. It allows evaporation, structure changes, more gentle, longer lasting and more lather. HP can sometimes require a longer cure due to the extra liquid required for the cook. 4-6 weeks is standard for all soap to be it's best.

I tried CPOP a few times but got silicone rash sometimes. I now just wrap them tight and let them do their own thing. Plus I make 6-7 loaves at a time and don't have enough room in my oven. I do CPOP individual molds by wrapping them in a towel on a cookie sheet and never have a problem.

Also, since you're new here please be sure to go over to the introduction forum and tell us a bit about yourself, your soaping experience etc. Welcome!
 
Ugh, I hate 'silicone rash'! I have a few different grades of silicone soap molds, one is a somewhat sturdy thick-walled, self-standing, white/translucent silicone log mold from Essential Depot, and the other is a thinner-walled, hot pink, very floppy/wobbly silicone tall & skinny log mold from Woodfields that came with an outer wood support box that it fits into like a glove. All things being equal in terms of soap formula, soap temps, trace thickness, FO, CPOP temp, etc...., the Essential Depot mold consistently gives my soap unsightly crater-like rashes, but the Woodfields mold does not: Below on the right, the typical rash I get from the ED silicone mold. On the left, the typical smoothness I get from my Woodfields silicone mold:
IMG_2425CroppedResizedContrastSilicone640.JPG



What is the most effective, consistent remedy that I've found for the 'silicone rash'? One to two swipes across my soap planer. lol :
IMG_2424CroppedResizedBayberryBubbles640.JPG





From my understanding HP and CPOP do NOT have to cure as long as CP. That's what I've been reading for a long time. Would love to hear if others concur.

Ditto what cmzaha, Shunt and Penelope said. There's a lot of misinformation on the net and even in some soapmaking books about cure. Most of it stems from a misunderstanding of the difference between saponification and cure, which are 2 very different processes. Saponification can be sped up through the application of heat (heat shortens the time it takes for raw soap batter to turn into soap that lathers and cleans), but although freshly made/unmolded HP, CPOP and fully gelled CP will all lather and clean from the get-go, there are still chemical changes going on inside the soap to help it mature to the best it can be in terms of the complete lathering, cleansing, hardness, gentleness, and longevity qualities/abilities that were built into the soap formula.

Here's an excellent post by our DeeAnna that peels back the curtain to see what's going on inside of soap once it's been saponified and is in the curing stage: https://www.soapmakingforum.com/threads/cure-time.35831/

For what it's worth, my HP batches take 2 to 3 weeks longer to catch up to my CP batches in terms of how long it takes them to mature/cure out to their best. For example, even though they are both zap-free and can be safely used within a time-frame of less than 24 hours of being molded, my CP soap lasts longer than my HP in comparison when used young, because of the extra water amount added to the HP.

Of course, 'best' is a relative thing from person to person, and no one is saying that one can't use soap the second it is zapless and thereby safe to do so, but only that there is so much more benefit to be reaped by waiting out a longer cure. It's good practice to hold back a bar from each batch and take notes on the changing qualities as it ages. It never ceases to amaze me how much better my soap is at 6 to 8 weeks, compared to 4 weeks when I consider it to be at it's earliest best.


IrishLass :)
 
ARGH. I wish I would have stumbled across this forum months ago. I, too, have had this problem with those flimsy flower molds you can by on Amazon. I did CPOP and kept thinking it was my soap formula - and kept changing the oils, etc. After combing through this forum, I see the problem resides in the molds themselves! So much time, ingredients wasted. Not to mention $.

Funny thing -- I don't have the same problem when I CPOP in my thick Brambleberry silicon molds. Just these cheap ones. There Brambleberry silicon molds do cause a little bubbling, but the cheap are just ridiculously full of bubbles. (I don't mind re the Brambleberry molds because I'm only making solid dish soap and shampoo bars. My first attempts at body soap in the flower molds was a disaster. I doubt HP would be any better result. And so...Look like for those cheap molds, CP is the way to go. (But I'm so impatient!)

Thanks Shunt2011 for your wisdom.


I have used the cheap Amazon flower molds for HP soap and I've never had a problem with bubbles appearing in the soap. I usually will place the molds on a sheet pan and bang the pan to release any air bubbles. In fact, I used the molds on Monday and didn't have a problem (except for the fact that I forgot to preheat the molds before I started filling the molds).
 
I have used the cheap Amazon flower molds for HP soap and I've never had a problem with bubbles appearing in the soap. I usually will place the molds on a sheet pan and bang the pan to release any air bubbles. In fact, I used the molds on Monday and didn't have a problem (except for the fact that I forgot to preheat the molds before I started filling the molds).
This is a heat rash caused by overheating the silicone mold.
 
When I say preheat, I mean place the molds in hot tap water to remove the chill - the dungeon is chilly in the wintertime.
Yes sorry, I didn't explain myself well.
I mean the silicone rash that causes the bubbles as displayed above is caused by serious over heating of the mold in the over when some people CPOP to 140-170*F and some leave the oven on as well and cook the soap in the mold.
This is not necessary. To CPOP you heat the oven to 110*F and turn it off before putting wrapped soap in the over. Then you won't destroy your molds and have every subsequent batch turn out with silicone heat rash even if you don't over heat the mold on the subsequent times.
 
Thank you everyone for chiming in. After reading a tip in this forum, I put the molds into the oven at 170 degrees for 15 or so minutes, just until the soaps gelled, and then pulled them out. A few hours later, when I popped them out of the molds, they looked great! (BUT -- they feel a little oily for some reason - is that normal? Orange is the one I cooked at 170 for 2 hours; pink I cooked at 170 for 15 minutes -- just until it gelled.).
soap molds.jpg
 
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I have used the cheap Amazon flower molds for HP soap and I've never had a problem with bubbles appearing in the soap. I usually will place the molds on a sheet pan and bang the pan to release any air bubbles. In fact, I used the molds on Monday and didn't have a problem (except for the fact that I forgot to preheat the molds before I started filling the molds).

What does HP look like in these intricate molds? I'd be curious to see a photo. Are you able to get the same level of detail using HP in these cheap flower molds as you would with CP?
 
Yes sorry, I didn't explain myself well.
I mean the silicone rash that causes the bubbles as displayed above is caused by serious over heating of the mold in the over when some people CPOP to 140-170*F and some leave the oven on as well and cook the soap in the mold.
This is not necessary. To CPOP you heat the oven to 110*F and turn it off before putting wrapped soap in the over. Then you won't destroy your molds and have every subsequent batch turn out with silicone heat rash even if you don't over heat the mold on the subsequent times.

Unfortunately 170 degrees is the lowest setting on my oven.
 
Ugh, I hate 'silicone rash'! I have a few different grades of silicone soap molds, one is a somewhat sturdy thick-walled, self-standing, white/translucent silicone log mold from Essential Depot, and the other is a thinner-walled, hot pink, very floppy/wobbly silicone tall & skinny log mold from Woodfields that came with an outer wood support box that it fits into like a glove. All things being equal in terms of soap formula, soap temps, trace thickness, FO, CPOP temp, etc...., the Essential Depot mold consistently gives my soap unsightly crater-like rashes, but the Woodfields mold does not: Below on the right, the typical rash I get from the ED silicone mold. On the left, the typical smoothness I get from my Woodfields silicone mold:
View attachment 44314

Thank you for your long and thoughtful answer.

IrishLass said:
What is the most effective, consistent remedy that I've found for the 'silicone rash'? One to two swipes across my soap planer. lol :
View attachment 44313

Unfortunately for these silicone flower molds, I cannot use a soap planer...




IrishLass said:
Ditto what cmzaha, Shunt and Penelope said. There's a lot of misinformation on the net and even in some soapmaking books about cure. Most of it stems from a misunderstanding of the difference between saponification and cure, which are 2 very different processes. Saponification can be sped up through the application of heat (heat shortens the time it takes for raw soap batter to turn into soap that lathers and cleans), but although freshly made/unmolded HP, CPOP and fully gelled CP will all lather and clean from the get-go, there are still chemical changes going on inside the soap to help it mature to the best it can be in terms of the complete lathering, cleansing, hardness, gentleness, and longevity qualities/abilities that were built into the soap formula.

Here's an excellent post by our DeeAnna that peels back the curtain to see what's going on inside of soap once it's been saponified and is in the curing stage: https://www.soapmakingforum.com/threads/cure-time.35831/

For what it's worth, my HP batches take 2 to 3 weeks longer to catch up to my CP batches in terms of how long it takes them to mature/cure out to their best. For example, even though they are both zap-free and can be safely used within a time-frame of less than 24 hours of being molded, my CP soap lasts longer than my HP in comparison when used young, because of the extra water amount added to the HP.

Of course, 'best' is a relative thing from person to person, and no one is saying that one can't use soap the second it is zapless and thereby safe to do so, but only that there is so much more benefit to be reaped by waiting out a longer cure. It's good practice to hold back a bar from each batch and take notes on the changing qualities as it ages. It never ceases to amaze me how much better my soap is at 6 to 8 weeks, compared to 4 weeks when I consider it to be at it's earliest best.

Thank you! I'm a newbie and appreciate the time you took to answer my question. I'm still learning.
 

We were all newbies once. And I, for one of many, learned from the wonderful, patient, helpful people here. When you get to where you can answer another newbie's questions, you need to pay it forward. Someone will be relying on your patient helpful answer in the future.
 
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