Shrinkage

[penelopejane]

Hi
How much does CP soap shrink by the time it cures?

I have marked soaps as "cut at 25mm" and "cut at 28mm"and cut at 32mm" "but now that I go back to see the shrinkage rate I have discovered that not one of them is cut straight so I have no idea which side was the 25mm or 32mm etc.

I would like to make a decision about a cutter and my dh is adamant that a 32mm (1 1/4 inch) bar (my preference when it is cut but not cured) is too big for his whopping great hand.

Can someone (with a more scientific mind that mine) please tell me how much soap that starts at 32mm or 1 1/4 inch (accurately cut) shrinks after a good cure?

 

[cmzaha]

All my bars are cut at 1.25" and no one complains. My customers like the larger bars

 

[Steve85569]

I *THINK* I have read that CP soaps shrink 10 to 15 % over the cure time depending on the amount of water ( and liquid additives) in the soap. Of course HP will shrink a bit less since a good amount of the excess moisture has been processed out.

 

[KristaY]

I haven't measured the width at cut then at cure but I do measure the weights throughout cure. My average weight loss is 6.8-8.0% and I use a water:lye ratio of 1.8:1 or 2.0:1. I haven't had anyone complain that the bars are too large or heavy but maybe he's finding the shape awkward? For him you might want to cut the bar fatter, like 2" then cut that in half through the center so instead of 2" thick by 3" wide you'd end up with 2" thick by 1 1/2" wide.

 

[penelopejane]

All my bars are cut at 1.25" and no one complains. My customers like the larger bars

Hi cmzaha,
Are your bard cut with a wire spaced at 1.25"? Can you please tell me how thick do they end up after cure?

I haven't measured the width at cut then at cure but I do measure the weights throughout cure. My average weight loss is 6.8-8.0% and I use a water:lye ratio of 1.8:1 or 2.0:1. I haven't had anyone complain that the bars are too large or heavy but maybe he's finding the shape awkward? For him you might want to cut the bar fatter, like 2" then cut that in half through the center so instead of 2" thick by 3" wide you'd end up with 2" thick by 1 1/2" wide.

The mold he likes is a tall and skinny and the soap ends up 2 1/8 wide x 3 inches tall. So they are small anyway.

 

[amd]

I used to cut mine 1.5" and after cure they were about 1.25". Now I cut closer to 1.25" and they are about 1.1" after cure. I had some complaints about the chunk size being difficult to handle so that's why I changed thickness..

 

[cmzaha]

Mine end up approx 1 3/16 after cure. I have small hands and have no issues with the size and never had a complaint. I do bevel the edges which makes them easier use.

 

[penelopejane]

I used to cut mine 1.5" and after cure they were about 1.25". Now I cut closer to 1.25" and they are about 1.1" after cure. I had some complaints about the chunk size being difficult to handle so that's why I changed thickness..

Mine end up approx 1 3/16 after cure. I have small hands and have no issues with the size and never had a complaint. I do bevel the edges which makes them easier use.

Thank you so much. That is exactly what I wanted to know.
I might bevel the edges just for my DH with the delicate hands. :mrgreen:

 

[shunt2011]

I too cut mine at 1.25" and bevel them. My customers seem to like the size of my bars and some have complained about other vendors who sell tiny bars It's a personal choice. I do make some guest size bars but not many.

 

[dibbles]

Hi penelopejane, I cut my bars at 1.25" as well and bevel the edges to make it easier to roll the bars in my hands when they are new. I use a single wire cutter, and the cut size is adjustable. You could cut some for DH that are a bit smaller and the rest a size you like with that kind of cutter rather than a fixed multi bar cutter. My molds are all 2.5 x 3.5.

 

[RobertBarnett]

I have the Essential Depot cutter which I believe cuts one inch. I don't notice a great deal of shrinkage.

Robert

 

[penelopejane]

Dibbles, my cutting (with a mitre box)is shocking [emoji33]. I was thinking of getting a multi wire cutter which is why I want to get it right. I think the bevelling for DH might solve his problem. Otherwise I'll use them for a few days before giving them to him [emoji2][emoji2][emoji2]

The best bar size so subjective - like FOs!

 

[SuzieOz]

I've just measured a heap of bars at various stages of cure. I always cut mine at 3cm, and after cure they have shrunk only within 2-3 mm.

They are obviously quite chunky and that's the way we like them. I've not had any complaints about the size either, people seem to like that they're getting a good size for money. They fit nicely in the hand, large but not too large. Bevelling them would make them feel more comfortable, but I don't usually bother.

 

[dillsandwitch]

I also have a multi-wire cutter that is set to 3cm. I get maybe a couple of mm shrinkage if even that as it isn't noticeable. And I like the fact that if I want a skinnier bar I can always cut to the 3cm and then shift the loaf and make them all 1.5cm thick.

 

[DeeAnna]

"... I always cut mine at 3cm, and after cure they have shrunk only within 2-3 mm...."

I know that doesn't sound like much, but that amounts to 7% to 10% shrinkage. When I look at it as percentages, it's really quite a bit.

And it's comparable to what others have been saying -- a weight and/or size loss of 10% give or take a bit. That's about what I see in my soaps too.