Soap Wire cutting hints

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penelopejane

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Hi,

I have a beautiful wire cutter from bud's woodshop. It is very well made.
The bars are the perfect width every time.

My problem I am having is that I can't work out the right time to cut. Even if I leave the soap a while so that it is almost too hard to cut through I get a sort of chalky, rough finish to the cut at the centre of the soap. It's not just the mark made by the wire.

Has anyone experienced this before or does anyone have a good technique for using a wire cutter?
 
Can you post a picture of the end result?

Also, are you tightening the wires enough. It takes a bit to know how tight and when you start on one end and work your way across, you will need to go back to the beginning and check that they are all "in tune".
 
I haven't had that happen to date. But, I don't wait long enough and sometimes end up with wire lines because I'm cutting too soon. I also sometimes get little bubble looking thinks on the bars. I'm sure a lot of it is getting it tuned just right and waiting long enough.
 
"...Even if I leave the soap a while so that it is almost too hard to cut through I get a sort of chalky, rough finish to the cut at the centre of the soap. It's not just the mark made by the wire...."

I have seen this a time or two in my soaps. The problem in my case is the soap didn't get warm enough during saponification. I soap with a high enough lye concentration that my soap doesn't necessarily gel, but if the soap gets warm enough as if it is thinking seriously about gelling, it doesn't have an unusual softness and powdery or chalky texture. If it doesn't get warm enough, it sometimes does have those problems.

I've found a gentle "CPOP after saponification" can correct this problem -- Put the soap back into its mold if needed, even if the soap is already cut. Preheat the oven to about 150 deg F and turn the oven off. Put the soap in the oven and leave it there until the oven cools down. Check to see if the texture is improved. The few times I've tried this, it has helped a lot. I still consider this an experimental tip, however, so use at your own risk.

If you think your soap is getting warm enough, the only other things I can think of that might cause this problem might be a recipe higher in linoleic acid and lower in palmitic and stearic acids than usual, a very high superfat, or an unusual amount of liquids and additives, including fragrance and colorants.
 
I haven't had that happen to date. But, I don't wait long enough and sometimes end up with wire lines because I'm cutting too soon. I also sometimes get little bubble looking thinks on the bars. I'm sure a lot of it is getting it tuned just right and waiting long enough.

I get that bubble looking things too, I think it's tiny soap balls made by the wire passing through. But i don't know how to stop it. I got a cheap wire cutter from Amazon and am afraid to let the soaps get much harder before trying to cut them as I felt like my wire was going to break on a less-than-24-hrs-old lard soap.
 
I have attached a photo. The soap on the left is cut with the wire cutter, the soap on the right is the same soap showing the side which was next to the mold (perfectly smooth). I can plane the marks left on the side cut with the wire cutter off and it is smooth again.

I CPOP at 100*F.

Soap wire cutter.JPG
 
I get that same look. All I do is smooth it with my thumb straight away after each cut and it comes up OK.
 
Thanks for the photo -- I have a better idea of what you're talking about now. It's different than what I had thought earlier.

I'd say for the most part that this texture is pretty normal for a wire cut soap, at least from what I've been seeing since I started using a wire cutter over a year ago. You know about mottling/rivers/streaking in soap, right? IMO, this texture is also from that same mottling -- you might not see the "rivers" in the soap, but they're there. The texture doesn't show up with a blade because the blade is stiff and heavy enough to cut through any slight changes in the hardness of the soap. A wire, being much lighter, can deflect as it goes through harder and softer bits.

Faster cooling might => more consistency, but I don't think the texture will entirely disappear. I also think it helps a little bit to make sure my hard fats are completely melted before I start soaping.

Just my opinion, so take it for what it's worth!
 
I get the same look with some of my soaps. I usually soap at 33% lye concentration and also CPOP so I can usually unmould and cut in about 6-8 hours depending on how lazy I am being. I find that running a damp cloth over the cut soaps before I put them on the drying rack sort od smooths the appearance of this down a bit. But to be perfectly honest it disappears after the first use anyways so I just embrace it like I do soda ash if I get it.
 
I have seen this a time or two in my soaps. The problem in my case is the soap didn't get warm enough during saponification. I soap with a high enough lye concentration that my soap doesn't necessarily gel, but if the soap gets warm enough as if it is thinking seriously about gelling, it doesn't have an unusual softness and powdery or chalky texture. If it doesn't get warm enough, it sometimes does have those problems.

I've found a gentle "CPOP after saponification" can correct this problem -- Put the soap back into its mold if needed, even if the soap is already cut. Preheat the oven to about 150 deg F and turn the oven off. Put the soap in the oven and leave it there until the oven cools down. Check to see if the texture is improved. The few times I've tried this, it has helped a lot. I still consider this an experimental tip, however, so use at your own risk.

If you think your soap is getting warm enough, the only other things I can think of that might cause this problem might be a recipe higher in linoleic acid and lower in palmitic and stearic acids than usual, a very high superfat, or an unusual amount of liquids and additives, including fragrance and colorants.

Thanks DeeAnna,

I will raise my lye concentration a bit and increase the temp I CPOP a tiny bit. But if I raise my lye concentration it won't gel will it? But CPOPing is trying to force Gel. So what happens to the poor confused soap?

I did put the soap photographed back into the oven but only turned it onto 100* F and turned it off. It made no difference. So probably not warm enough?

It happens with pure OO and my other recipe which both have low SF and with FO or without so I don't really think it is the recipe. I do take a lot of trouble to melt my hard oils and mix them thoroughly before I mix in the lye. I will try the above and then might invest in a planer : ))
 
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"... But if I raise my lye concentration it won't gel will it? But CPOPing is trying to force Gel. So what happens to the poor confused soap? ..."

CPOP adds warmth to encourage saponification. That often means the soap goes into gel, but it doesn't have to. Your lovely soap is not confused at all -- it's just doing what comes naturally. :)

"...I did put the soap photographed back into the oven but only turned it onto 100* F and turned it off. It made no difference. So probably not warm enough?..."

I now don't think my first suggestions apply to your specific situation -- the "after the fact CPOP" wasn't really necessary for your soap. When I wrote that, I was going off your word description -- it sounded to me as if your soap might not have gotten warm enough during saponification to firm up properly.

After you shared your photo, the soap looks fine and I changed my opinion. The ripply surface on the bar looks like a normal type of texture for a soap cut with a wire, so warming the soap again didn't hurt anything -- but it didn't help much either.
 
".
If you think your soap is getting warm enough, the only other things I can think of that might cause this problem might be a recipe higher in linoleic acid and lower in palmitic and stearic acids than usual, a very high superfat, or an unusual amount of liquids and additives, including fragrance and colorants.

In your tutorial on citric acid you say add it to 2x it's weight if water and add it to the oils. Should I be adding it to the lye water? Could this effect the SF and consequently causes these marks?
 
Water based liquids can't affect superfat -- you aren't changing the lye nor changing the fats. Yes, you can add citric acid to the water that you're using to make the lye solution if you prefer; a number of people are uncomfortable doing that because the reaction between citric acid and lye causes extra heating of the lye solution.

If you choose (as I suggest) to dissolve the citric acid in 2 times its weight of water and then add to the fats, the water should be a portion of the total liquid called for in your recipe -- it shouldn't be extra water in addition to the water in the recipe. It didn't occur to me that one might interpret this advice as to add even more water. I will have to re-word that sentence.
 
Water based liquids can't affect superfat -- you aren't changing the lye nor changing the fats. Yes, you can add citric acid to the water that you're using to make the lye solution if you prefer; a number of people are uncomfortable doing that because the reaction between citric acid and lye causes extra heating of the lye solution.

If you choose (as I suggest) to dissolve the citric acid in 2 times its weight of water and then add to the fats, the water should be a portion of the total liquid called for in your recipe -- it shouldn't be extra water in addition to the water in the recipe. It didn't occur to me that one might interpret this advice as to add even more water. I will have to re-word that sentence.

No I haven't added more water. Your wording does not imply that.
It is just that someone on this forum said CA must be added to the lye water or it will not turn into citrate. He said if you add CA to the oils it will not make the required reaction.
Do you think adding the CA to the lye water would stop the marks on my soap?
 
It's true the citric acid has to "meet" some active lye (whether KOH or NaOH) sooner or later. It doesn't really make a lot of difference whether the CA and lye meet sooner in the lye solution or whether the CA and the lye meet a moment later when you mix the fats and lye solution. I certainly hope nothing I've said about using citric acid is misleading any one about this point.

I don't think changing when you add citric acid will make any difference to how your wire cutter cuts your soap. As Shari and I have mentioned, your soap in the photo looks very typical for a wire cut soap.
 
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I suspect any closeups of the cut soap have been planed. I'm kinda bummed about the surface left by the wire too! Thinking of getting a miter box and straight blade myself.
 
I had about the same reaction at first, but I've gotten a little less perturbed as time went on.

As I've been paying more attention to this issue, I've learned a few things that I didn't notice before. One is that my soap tends to form a slightly textured surface as it cures, even if cut with a blade or planed smooth. Again, I think it's those (often invisible) rivers/mottles/streaks at work. The high-low water soaps I made for the SMF challenge (in November or December, 2015) really showed this effect. What's paradoxical is the texture from the wire cutter tends to to become less obvious as the soap cures/dries.

I even did a little experiment a few months ago -- I left one side of a wire cut bar as-is, planed the other side to a silky smoothness, and let the bar cure as usual. The wire cut side is still more textured than the other side, but the planed side now shows some texture as well.

So .... I've mostly gotten over being annoyed and wanting to plane all my soaps. HTH!
 
As I've been paying more attention to this issue, I've learned a few things that I didn't notice before. One is that my soap tends to form a slightly textured surface as it cures, even if cut with a blade or planed smooth. Again, I think it's those (often invisible) rivers/mottles/streaks at work. The high-low water soaps I made for the SMF challenge (in November or December, 2015) really showed this effect. What's paradoxical is the texture from the wire cutter tends to to become less obvious as the soap cures/dries.

I even did a little experiment a few months ago -- I left one side of a wire cut bar as-is, planed the other side to a silky smoothness, and let the bar cure as usual. The wire cut side is still more textured than the other side, but the planed side now shows some texture as well.

So .... I've mostly gotten over being annoyed and wanting to plane all my soaps. HTH!

Hi DeeAnna,
In my latest soap I have greatly improved the cut! You can see the result in the challenge.
I tightened the wires so they were really really tight.
I used 33% lye concentration (probably not a good idea as I was doing the challenge!!!)
And I heated the oven to 140*F, wrapped the soap in a blanket and did not open the oven once until the next day.

I am really pleased with the texture. It really doesn't need planning. Now, unfortunately, I am not quite sure which one of those effected the soap as I did them all at once! :silent::silent::silent:

Thank you for persisting with recommendations.
 
I have attached two soaps. The plain grey spotty one is the first attempt at this colour. The second photo is the second attempt that I just cut. Poured last night so it is 18 hours old. It has 1tsp salt in the batter, 1tsp salt in the water, vanilla bean seeds and AC as colourant. The Perfect Man FO also discolours.

It is my first in the pot swirl and I also used the hanger tool. I wanted two different greys swirls and a cream top. Next time I will make the dark grey a tiny bit darker, the creamy grey the same colour as the dark grey and put an even heavier AC very thin swirl through it. Keeping the cream top. Do you think that would look better?

I was so excited to actually have a bar to cut that was a normal recipe (not confetti, 35% salt etc) to show you how I had improved my wire cutting technique that it wasn't until I looked and realised the salt in the batter is showing through as an imperfection! So next plain batch I make I will post another one!

It is not what I was aiming for as a finished artistic product for my son but he will love it because he likes AC and salt.

I still think you will be able to see the vast improvement I have made in the finished surface of the soap just by doing two things: 33% Lye concentration (up from 30%) and tightening the strings really, really tight. It is a huge difference up close and personal. :)

22 Grey speckles.JPG


36 Grey Swirl.JPG
 
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