Cylinder PVC Molds

[ShirleyHailstock]

I made two cylinder molds using PVC pipe. While in the store, I found they had caps that fit on the pipe and I bought them. When I make the soap, I can cap the bottom (obviously), but when the tube is filled (one inch from the top), can I cap the top and leave it upright or should I close it by rubber banding it with a wrapping of paper and saran wrap?

I'm wondering if the airtight container will affect the heat level of the soap making too hot.

Thanks for your help.

 

[Anstarx]

I also have pvc pipe mold with caps. I put plastic wrap (microwave safe kind) at one end and cap over that, wrap rubber band around the excess plastic, then put another plastic bag around the bottom, also secured with rubber bands. After that I put the whole thing in a bucket and weight it down with bags of sand. Better safe than sorry when using pipes.
If I used igredients that I know will cause heating, I wrap ice packs around the pipe, the kind you use for injured knees, etc. They are not frozen but colder than room temp by sitting in the fridge.

 

[Susie]

PVC pipes are well known for heating more than other kinds of molds. It is the fact that it is vertical and that PVC is a good insulator. If you want to gel, and have any ingredients that are known heaters/accelerators (sugar, honey, milks, EOs/FOs), I might leave more than 1 inch of head space before the top cap in case it tries to volcano. If you don't want to gel, I would have a vertical space in a freezer (or as someone on another thread suggested) a handy snowbank to plunge it into immediately. I only have upright freezers at home, and as I am from Texas, no snow. If it were me, I would have a 5 gallon bucket filled with ice water to plunge it into, with more ice ready to dump in there. And be prepared to stay up 24 hours refreshing ice as needed to avoid it....Me, I like gel.

 

[ConcowMomma]

Do you line the pvc? How does the soap come out?

 

[ShirleyHailstock]

Do you line the pvc? How does the soap come out?

I haven’t used it yet. I ask here because I don’t want an accident.

PVC pipes are well known for heating more than other kinds of molds. It is the fact that it is vertical and that PVC is a good insulator. If you want to gel, and have any ingredients that are known heaters/accelerators (sugar, honey, milks, EOs/FOs), I might leave more than 1 inch of head space before the top cap in case it tries to volcano. If you don't want to gel, I would have a vertical space in a freezer (or as someone on another thread suggested) a handy snowbank to plunge it into immediately. I only have upright freezers at home, and as I am from Texas, no snow. If it were me, I would have a 5 gallon bucket filled with ice water to plunge it into, with more ice ready to dump in there. And be prepared to stay up 24 hours refreshing ice as needed to avoid it....Me, I like gel.

I want it to gel. I don’t want it to explode. It looks like the option of using a rubber band over a paper covering is the better option to prevent a volcano.

 

[Rsapienza]

Do you line the pvc? How does the soap come out?

Some people line, some don't. I personally do not. I give it a good whack on the concrete, and it slides out.

 

[soapmaker]

I'm not sure why you cover the top at all. At least I don't. I cap the bottom and let the top open. I've never had a volcano. I stand the pipes upright in a cardboard box that is a few inches taller than the molds. It gels. After a few days I put it in the freezer for an hour or so, then it gets a little slippery after removing from the freezer and pushes out. You have about 1/2" to trim off the top. I did line for awhile but the plastic left wrinkle marks in the soap.

 

[ShirleyHailstock]

I'm not sure why you cover the top at all. At least I don't. I cap the bottom and let the top open. I've never had a volcano. I stand the pipes upright in a cardboard box that is a few inches taller than the molds. It gels. After a few days I put it in the freezer for an hour or so, then it gets a little slippery after removing from the freezer and pushes out. You have about 1/2" to trim off the top. I did line for awhile but the plastic left wrinkle marks in the soap.

My reason for thinking the top needs to be closed is because of the reading I've done on making soap. Since we cover a rectangular mold and then wrap it with towels, I figured I needed to do the same to the PVC mold. Since it has a cap, I thought of using it, then remembered the heat notes I've read.

I'm a newbie, so I'm trying to NOT make a mistake.

 

[artemis]

Since we cover a rectangular mold and then wrap it with towels...

I often leave my loaf mold uncovered and stick it in the oven. The only covering I regularly do: drape the bars with a light cloth to keep dust off. I haven't capped my cylinders, but I could see doing it if I were afraid that it would fall over.

 

[artemis]

I'm a newbie, so I'm trying to NOT make a mistake.

Also, mistakes help you learn and make for great stories later.

 

[Kcryss]

Do you line the pvc? How does the soap come out?

I bought flexible cutting mats from the dollar store and cut them to fit around the inside of the pipe. Not my "original" idea ... borrowed from a youtube soaper.
She also used bubble wrap on the inside to make it look like honeycomb. I tried that too on one and it came out looking like a corn cob.

 

[bookreader451]

My reason for thinking the top needs to be closed is because of the reading I've done on making soap. Since we cover a rectangular mold and then wrap it with towels, I figured I needed to do the same to the PVC mold. Since it has a cap, I thought of using it, then remembered the heat notes I've read.

I'm a newbie, so I'm trying to NOT make a mistake.

When I have done PVC and Pringles cans I have left enough freezer paper extended on the top to lightly fold over the soap batter. It isn't airtight and heat can escape.

 

[ShirleyHailstock]

When I have done PVC and Pringles cans I have left enough freezer paper extended on the top to lightly fold over the soap batter. It isn't airtight and heat can escape.

Thank you. This helps.

 

[soapmaker]

My reason for thinking the top needs to be closed is because of the reading I've done on making soap. Since we cover a rectangular mold and then wrap it with towels, I figured I needed to do the same to the PVC mold. Since it has a cap, I thought of using it, then remembered the heat notes I've read.

I'm a newbie, so I'm trying to NOT make a mistake.

I don't gel my CP soap so I just let it sit on the counter uncovered and unwrapped. I used to cover and got so much ash. But after I learned to do a water discount, doing that + leaving uncovered has resulted in no ash. After trying different things, you will eventually find what works best for you.

https://www.modernsoapmaking.com/lye-solution-in-soapmaking/

 

[Noreen Moore]

Corn cob! Lol! I was going to try that! Thinking twice now! Giggle!

 

[Noreen Moore]

@ Shirley Hailstock I leave a tad bit of headspace too. I used to use Pringles cans and had a soap grow an eighth of an inch out of the can once.
I line mine with parchment paper. Smear a little Vaseline on the PVC and where the parchment overlaps and it holds it in place nice without wrinkles. I do freeze it for an hour. And a good whack to the pipe it slides out nice. Haven't tried it without a liner yet.
I want to see your soap when you give it a go in your PVC pipe! You've got this Shirley!

 

[Kcryss]

Corn cob! Lol! I was going to try that! Thinking twice now! Giggle!

lol, once they were cut it looks like honeycomb, but the cob thing was funny.

 

[Noreen Moore]

OMG. OMG !!!!
I do like the sliced version!
That is an awesome corn cob!

 

[ShirleyHailstock]

@ Shirley Hailstock I leave a tad bit of headspace too. I used to use Pringles cans and had a soap grow an eighth of an inch out of the can once.
I line mine with parchment paper. Smear a little Vaseline on the PVC and where the parchment overlaps and it holds it in place nice without wrinkles. I do freeze it for an hour. And a good whack to the pipe it slides out nice. Haven't tried it without a liner yet.
I want to see your soap when you give it a go in your PVC pipe! You've got this Shirley!

Thanks. I so want to jump up and try this, but I have an overdue deadline to get through first. Everytime I past the dining room, where the pipes are on the table, I think maybe I could try this but then I know I'll get involved and focused and miss another (paying) deadline. Gotta prioritize!

 

[Kcryss]

OMG. OMG !!!!
I do like the sliced version!
That is an awesome corn cob!

I've used the bubble wrap idea before in a soap mold. In fact, did it with my first batch of soap. Not so dramatic looking. lol