outside bubbles on my CPOP?

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denisedh

Member
Joined
Dec 12, 2014
Messages
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Location
North Carolina
Hi Soap Gurus,

I'm new - this is my second loaf of CP and I followed a recipe on Brambleberry to CPOP it. It has been two days and I unmolded it from a silicone liner (from Essential Depot) I am still not sure at all about the way things are supposed to look but I think this was too tight for Cpop and formed the bubbles around the edge.

what to do now? I would appreciate any advice at this busy holiday time! Attached pics \\
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Denise in NC
 
Thank you so much!!

Just Beachy, Obsidian and Shunt2011,

Thank you so much for replying so quickly! I will not CPOP again with that liner or maybe ever - until I get more used to this soap making!

I see a shiny section in the middle top but I am still going to cut it later today. If the first piece feels at all squishy I will wait longer.

The bubbles will probably be planed off.

Thank you again!

denise
 
I always use silicone liners, I always CPOP, and I never get bubbles. I'm always mystified when I hear people say this, because it has never happened to me. You'd think that as many batches as I've made, it would have happened at least once! I wish we could get to the bottom of this.
 
I always use silicone liners, I always CPOP, and I never get bubbles. I'm always mystified when I hear people say this, because it has never happened to me. You'd think that as many batches as I've made, it would have happened at least once! I wish we could get to the bottom of this.


I wonder if the actual thing that the liners are lining has an impact on this? Is your mould thicker or thinner than the ones used by people who do get the issue?
 
I use silicone liners and when they're brand new I get these bubbles with or without cpop. It seems after 2 or 3 batches it stops happening and the liners leave the soaps perfectly smooth. It's almost like they need to get broken in. Just my thoughts and it could have nothing to do with that. I have 2 new liners on order and am prepared for the bubbles at first.
 
I do CPOP with my silicone molds and liners, and I've found that if I turn the heat really low, then off as soon as it goes into the oven, I don't have any bubbles. Also give it some good sprays with alcohol. I love CPOP, it produces such a gorgeous bar!
 
I always use silicone liners, I always CPOP, and I never get bubbles. I'm always mystified when I hear people say this, because it has never happened to me. You'd think that as many batches as I've made, it would have happened at least once! I wish we could get to the bottom of this.

That is interesting. I wonder if what vivian is saying has anything to do with it? I don't own any silicon liners, or I'd run some tests. If it stops after a few soaps, maybe a silicone liners needs to be "seasoned".

These unanswered questions drive me crazy. :)
 
I have never had a problem with bubbles, right from the very first batch. No "seasoning" necessary. I don't understand why some have this problem all the time. Actually, in various forums I've read over the years, I've only heard about this problem recently. I'd say maybe the newer silicone liners are manufactured differently from the older ones, but I've bought some recently and not had problems with those either. Old.....new.....loaves.....individual molds.....different recipes, never a problem. I'm stumped!
 
very interesting~

I use silicone liners and when they're brand new I get these bubbles with or without cpop. It seems after 2 or 3 batches it stops happening and the liners leave the soaps perfectly smooth. It's almost like they need to get broken in. Just my thoughts and it could have nothing to do with that. I have 2 new liners on order and am prepared for the bubbles at first.

Mine is obviously a brand new silicone liner - I wonder if the lye is breaking in the silicone? This is a bad case of bubbles - all over the whole brick.

But....the first batch of soap I made (from the starter kit from ED) was perfect - not one bubble. I just remembered that - it is cut and drying - 3 weeks.

Denise
 
I'll put some time into trying to figure it out. I haven't given it much thought, due to never using silicone liners. Navigator, can you post which liners you have used and are using? And denise, which liner did you use?
 
Denise- I have a couple of silicone molds- one made by the same company as your mold (Essential Depot), and a different one made by Woodfield's. The Woodfield liner is a dream to work with and never gives me bubbles when I CPOP. I wish I could say the same about the ED silicone mold, but unfortunately, I get the same bubbling issue with the ED mold that you do:

On the left is a perfectly smooth soap made in my Woodfield silicone mold (well, perfectly smooth except for the little air bubble about halfway down from having poured at extremely thick trace), and the soap on the right is a batch soaped in my ED mold. The bubbles that you see in that soap are a typical example of what I get each time I soap in that mold. Thankfully, they are just surface bubbles that plane off nicely.
IMG_2425CroppedResizedContrastSilicone640.JPG


In comparing the two molds, it is quite obvious they are made out of two different silicones. The ED mold is stiff and can stand up on it's own without the sides bowing inward, while the Woodfield's is considerably softer (and smoother-feeling) and the sides bow inward when standing on it's own, but straighten out nicely when I pour my soap into it.

I could be wrong, but if you ask me, I think the different type of silicone each is made from has something to do with it.


IrishLass :)
 
I'll put some time into trying to figure it out. I haven't given it much thought, due to never using silicone liners. Navigator, can you post which liners you have used and are using? And denise, which liner did you use?

I have several different liners from different suppliers. My two original liners come from the Upland company, which is no longer in business. I also have one of the "stiffer" kind, from WSP, that doesn't need a box around it, you know the kind I mean, BB has them too. And most recently, I bought one from Nurture Soaps when they had a great sale.

My soaps always look like Irish Lass's on the left, I've never had one that looked like the one on the right. I soap at room temp these days, but I haven't always, and I never had a bubble problem when I didn't. I warm the liner in the oven while I'm soaping. Put it back in the oven after pouring, and turn the oven off, but there are times I've forgotten to turn it off, and only noticed when I went back later to check for gel. If I notice that it's gelled all the way, I take it out of the oven, but there are times when I've had to leave for work, and just left it there, with the oven off. The main oils I use are olive, coconut and palm, I don't usually add castor, but I do use avocado, and sometimes shea. I've made goat's milk, buttermilk, yogurt, coconut milk soaps. I'm trying to think of as many variables as I can, because I figure that those who get bubbles must have something in common, that I don't do, or add, and I'm sure someone out there is smart enough to figure out what it is. I sure hope so, because silicone liners have been nothing but a joy for me.

Also, as I mentioned before, is this a recent phenomenon? I've perused many soap forums over the years, and I don't remember reading anything about this problem until recently. That lead me to think that maybe the newer liners were manufactured differently, but since I recently bought one from Nurture Soaps and had no problems, I guess we can rule that out. Did I just miss this in other forums, or has it been going on all along? It just seems odd to me that over the years, using different molds and different recipes, and always CPOPing, that I've never encountered this problem once!
 
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Irish's experience and pics, as well as yours Navigator, lend a lot of credibility to the type of silicone being the culprit. Here's a paragraph from a discussion on the different types of high temperature silicone, for kitchen products.

"The high temperature silicone designation is actually somewhat misleading because silicone products in general feature excellent heat resistance qualities. There are, however, silicone products specifically formulated to deliver elevated levels of heat resistance. The average general purpose silicone product can comfortably resist constant exposure to temperatures in the region of 100°F to 150°F (37–65°C). High temperature silicone products specifically designed for use in aggressive thermal environments pick up at approximately that temperature level with low grade products rated at 150 to 200°F. The big guns among these products can withstand constant exposure to 400°F (405°C) with short peaks as high as 500–600°F (260–315°C) without suffering any ill effects."

Different articles talking about high temperatures and silicone gaskets, talk about the degradation of the silicone producing a gas, which sounded interestingly like something that would create the air bubbles. There was a lot of technical information about the chemical reaction that was taking place, that DeeAnn would probably love. :) My take on it, is any chemical reaction that is taking place in the silicone liner as it heats to temps that the silicone isn't rated for, could be the culprit in the air bubbles.

Looking up the Woodfield molds, they don't really say what type of silicone the liner is made with, but perusing the Q&A, there is a question of why they are more expensive. With the response being, that the silicone is a high grade silicone.

I'll keep looking but I'm leaning towards the type of silicone used. Specifically due to the "average general purpose silicone", being able to resist temperatures up to 150F and CPOP being done at 170F for an extended period. Then the high temperature silicone holding up to 200F, which would mean it's not breaking down at the CPOP temperature. It wouldn't surprise me if a lot of the silicone molds/liners were being made with the general purpose, cheaper silicone.
 
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I did a google search, and one reference I found said the bubbles have to do with a super hot gel phase. Don't know it that's true, but I guess anything is possible. For those of you who get the bubbles, I wonder what would happen if you preheated the molds, but just wrapped them in towels after pouring, and not put them in the oven. Maybe you have too much heat being generated? Maybe preheating and wrapping in towels would provide just enough heat for full as opposed to partial gel, but not enough to get bubbles? I'm grasping at straws here, but it's just such a shame to spend the money on silicone liners only to have your soap end up looking like Swiss cheese!

Also, for those of you with the ED liners, have you contacted the supplier to see if they have any suggestions? I'd show them that picture Irish Lass, and see what they have to say. You shouldn't have to plane soap off of every batch made in their molds.
 
I'll keep looking but I'm leaning towards the type of silicone used. Specifically due to the "average general purpose silicone", being able to resist temperatures up to 150F and CPOP being done at 170F for an extended period. Then the high temperature silicone holding up to 200F, which would mean it's not breaking down at the CPOP temperature. It wouldn't surprise me if a lot of the silicone molds/liners were being made with the general purpose, cheaper silicone.

I would go along with this, except for the instances of those who had bubbles, but then didn't, after their mold was used a few times. This is really perplexing.

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