Wax melter

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You're scaling up the volume. Have you scaled up the intensity of mixing? And are you testing for zap? How did you make the soap?

"...Could it be the temp. was to low when adding the KOH?..."

How can anyone possibly answer that question, given what little you have shared in your post? You did not share any info on temps or anything else about your procedure.

Yes, I sound testy. My background is in process engineering and one of the things I've done as a process engineer is scale up processes from lab scale to full industrial scale. You have to keep better records and provide more info in order to troubleshoot problems like this.
 
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You're scaling up the volume. Have you scaled up the intensity of mixing? And are you testing for zap? How did you make the soap?

"...Could it be the temp. was to low when adding the KOH?..."

How can anyone possibly answer that question, given what little you have shared in your post? You did not share any info on temps or anything else about your procedure.

Yes, I sound testy. My background is in process engineering and one of the things I've done as a process engineer is scale up processes from lab scale to full industrial scale. You have to keep better records and provide more info in order to troubleshoot problems like this.

I went from a stick blender to a paint mixing tool on a drill. I did a zap test and it passed.
The temp of the oil was about 131F when I added the KOH that was 140F ( I must say my thermometer sucks )
My wax melter was set to 170F but the oils where not much hotter than 135F and I mixed for 1 hour and 30 min finally it traced and I theft it overnight in the pot that keep the heat. It looked translucide so I went ahead and zap tested and that turned out ok. At first when diluting it looked clear but after 2 day it was cloudy with a very thin white film on top. ( I did use a wooden spoon in the paste if that matters)

Thanks for any thoughts

P.S. I dont care if you seem a little testy ( I am thankful of all the know how on this forum )
 
I am not sure exactly what you are asking, so pardon the hesitation. I will endeavor to explain some things that might be causing issues.

1. I have used room temperature oils and KOH/water with no problem.
2. You need something to speed trace if you are not happy with that long time to trace.
3. You really only need to get it emulsified, then leave it alone to get to trace and gel.
4. A wooden spoon would not be my choice, but unless it was loaded with excess oils, it is not the cause of the film on top.
5. Are you sure your scale is accurate? You should not have a white film (unless it is foam) on top with a 0% SF. Did you add any fragrances?
 
I am not sure exactly what you are asking, so pardon the hesitation. I will endeavor to explain some things that might be causing issues.

1. I have used room temperature oils and KOH/water with no problem.
2. You need something to speed trace if you are not happy with that long time to trace.
3. You really only need to get it emulsified, then leave it alone to get to trace and gel.
4. A wooden spoon would not be my choice, but unless it was loaded with excess oils, it is not the cause of the film on top.
5. Are you sure your scale is accurate? You should not have a white film (unless it is foam) on top with a 0% SF. Did you add any fragrances?

I will check the scale but it is a industrial scale that always worked in the past, this recipe worked perfect in a pan on direct heat. no fragrances.
thanks for your ideas
 
What Susie said. Some other thoughts --

Vessel size -- If I'm calculating things right, you are making roughly 2 gallons (8 liters) of soap paste in a 20 gallon (80 liter) container. If I'm correct on this point, you are using wayyy too big of a vessel for that amount of soap paste -- you need to be making this in more like a 5 gallon bucket, not a 20 gallon vessel. For efficient conservation of heat and the most efficient mixing, you want your soap batter to be as close to a sphere in shape -- not spread out like a rain puddle on the sidewalk.

Intensity of mixing -- you will get more efficient and complete mixing of a liquid if the liquid is deeper rather than shallower. Furthermore, you've dropped your intensity of mixing by switching from a stick blender to a paint stirrer. That's maybe something you'll have to live with, but you're going to have to understand that a paint mixer is not going to work well when you eventually scale up to a full 20 gallon batch. Most people using that size of vessel are using an industrial "stick blender" not a paint stirrer. Maybe something vaguely like this: http://www.zesco.com/Dynamic-SMX800E-Commercial-Immersion-Blender-27-Shaft-pz523D005.htm

Think about it -- If your smaller-scale soap making equipment is anything like mine, the batter in your small soap pot is about as deep as it is wide. That's what you want for your scale up conditions too. You're going to keep the batter at a more consistent temp and you are going to spend less energy and time getting it emulsified if you do this.

If you really want to get the best out of this investment, then I suggest you consider getting away from the paste method of making liquid soap and go to an "all in one" method where most or all of the dilution water is added up front. This method has little or no dilution at the end -- your batch size is fairly consistent from start to finish. Further, you won't have to deal with the thick paste which can be difficult in small batches and a terror as a large batch. With this type of process, you can use a lower intensity continuous-duty mixer and just plan on mixing for a longer time. Although some people do this kind of "all in one" liquid soap making on a hobby scale, it's more practical on a larger scale.
 
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What Susie said. Some other thoughts --

Vessel size -- If I'm calculating things right, you are making roughly 2 gallons (8 liters) of soap paste in a 20 gallon (80 liter) container. If I'm correct on this point, you are using wayyy too big of a vessel for that amount of soap paste -- you need to be making this in more like a 5 gallon bucket, not a 20 gallon vessel. For efficient conservation of heat and the most efficient mixing, you want your soap batter to be as close to a sphere in shape -- not spread out like a rain puddle on the sidewalk.

Intensity of mixing -- you will get more efficient and complete mixing of a liquid if the liquid is deeper rather than shallower. Furthermore, you've dropped your intensity of mixing by switching from a stick blender to a paint stirrer. That's maybe something you'll have to live with, but you're going to have to understand that a paint mixer is not going to work well when you eventually scale up to a full 20 gallon batch. Most people using that size of vessel are using an industrial "stick blender" not a paint stirrer. Maybe something vaguely like this: http://www.zesco.com/Dynamic-SMX800E-Commercial-Immersion-Blender-27-Shaft-pz523D005.htm

Think about it -- If your smaller-scale soap making equipment is anything like mine, the batter in your small soap pot is about as deep as it is wide. That's what you want for your scale up conditions too. You're going to keep the batter at a more consistent temp and you are going to spend less energy and time getting it emulsified if you do this.

If you really want to get the best out of this investment, then I suggest you consider getting away from the paste method of making liquid soap and go to an "all in one" method where most or all of the dilution water is added up front. This method has little or no dilution at the end -- your batch size is fairly consistent from start to finish. Further, you won't have to deal with the thick paste which can be difficult in small batches and a terror as a large batch. With this type of process, you can use a lower intensity continuous-duty mixer and just plan on mixing for a longer time. Although some people do this kind of "all in one" liquid soap making on a hobby scale, it's more practical on a larger scale.

"All in one" method??? I will search the forum to see if this has been covered but im interested. Thank you again
If that really is something great for me I will send you some Swiss chocolate ( if you like chocolate? )
 
I don't have a good reference for you. It's only been mentioned a time or two on SMF that I recall. I do not remember any discussion that would be useful to someone who wants to use the technique. It would be a tough method for a small-scale hobby soap maker to use, so there is not a lot of info out there.

There is (or was) a video on YouTube from a soapmaking company that makes liquid soap with this method. They use a vessel that looks to me to be about 200 gallons (800 L) in size. It has a low speed mixer that runs continuously during saponification. Continuous mixing for some hours would be really critical, and that is the hard thing for a hobby soap maker to provide. The video doesn't give much detail other than that -- I'd give you a link, but I can't find it now.
 
I don't have a good reference for you. It's only been mentioned a time or two on SMF that I recall. I do not remember any discussion that would be useful to someone who wants to use the technique. It would be a tough method for a small-scale hobby soap maker to use, so there is not a lot of info out there.

There is (or was) a video on YouTube from a soapmaking company that makes liquid soap with this method. They use a vessel that looks to me to be about 200 gallons (800 L) in size. It has a low speed mixer that runs continuously during saponification. Continuous mixing for some hours would be really critical, and that is the hard thing for a hobby soap maker to provide. The video doesn't give much detail other than that -- I'd give you a link, but I can't find it now.

I will try a big batch in my wax melter when I have enough oils and change the recipe.

Thank you:bunny:
 
As a process engineer who has done scale-up work, I strongly advise that you begin to develop the "all in one" method on a much smaller scale. This is not a process you are going to figure out in one or two trials! Start with a recipe that uses 500 grams of oils and scale up once you have a better idea of what you are doing.

Here's a reference about scaling up using the usual "make paste then dilute" method. http://chemistscorner.com/cosmetics...id-soap-production-do-i-really-need-a-machine

This video is poorly made and not especially helpful, but it will give you a rough idea of what the "all in one" process might look like during saponification. [ame]https://www.youtube.com/watch?v=Vd3hhgJssI4[/ame]
 
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It looked translucide so I went ahead and zap tested and that turned out ok. At first when diluting it looked clear but after 2 day it was cloudy with a very thin white film on top. ( I did use a wooden spoon in the paste if that matters)

Thanks for any thoughts

You need to rule out some of the simpler more obvious problems before going into the more complicated. I think you didn't have enough KOH to saponify all your oils. Even a small residual oil will cause clouding and a film to form. 0% superfat is never perfectly accurate because KOH purity and oil SAP values change from batch to batch. Liquid soap is unforgiven of excess oil. The zap test doesn't help here because it tells you about residual lye in your batter but not residual oil.

My suggestion is to take a kg of paste, melt it and add additional KOH to drop the superfat to -5%. Let it cook for an hour or so on low heat and repeat the dilution. If it clears, you identified your problem. Any excess lye can be neutralized with citric acid. If you have a pH meter or pH paper, you can use them to help you get the soap into the right pH range. You're not trying to be 100% accurate with the pH. You just need to be in the right range.

Learning how to scale up is also important. You need to start smaller, repeat repeat and repeat the process until you are very comfortable with it, then scale up again.
 
That's the video I was thinking about -- THANK YOU, Carolyn! This shows the larger vessel with continuous agitation and an external heating jacket. It also shows the concept of adding the alkali as a solid directly to the water and fats in the vessel. That's certainly not the norm for hobby soap making, but it works fine in this context.
 
Try what Soapmaker145 suggested, for a start. It might be as simple as that. Also, Macherey-Nagel strips work well with liquid soap if you need to check pH.

As an aside, be careful of brass fittings on some of these melters. There should be no brass involved in soapmaking. You might be able to find stainless steel fittings to replace them.

Thanks for the tips I will post as soon as I test it.
 
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