Making a Plaster Hump Mold for Pottery

Plaster hump molds are a great way of making hand-built pottery. They are also known as drape molds. They can be expensive to buy, but they are so incredibly easy to make. And if you make them yourself, you can choose exactly what shape you want.
Also, check out my video on how to use your plaster hump mold to make beautiful pottery.

[@agnediciuniene9861]

I put a string in plaster so that the loop is sticking out. When the plaster is dry it shrinks some, then I pull on a string and get the mold out of glass container. 🙂

[@ThePotteryWheel]

Aha! great idea. thanks :)

[@tarazanjani4770]

Thank you for sharing.I would like to make couple of them.

[@susanl2618]

Thank you so much ... it's so generous of you to share this. :)

[@sharonatseanicstudios9970]

Another helpful lesson. Thank you

[@juliebestic8151]

Wonderful thank you❤

[@fizzilemon]

Very helpful, thanks!

[@ThePotteryWheel]

Hi Elizabeth, glad it helped!

[@kellysunday7781]

I found bubble holes on the surface of my finished mold. Any tips on removing, sanding, or filling?! Thank you for your great videos!❤🎉❤

[@ThePotteryWheel]

You could try sanding the bubbles out. If you're sanding plaster wear a mask though as the dust is fine. The only issue with sanding and filling is that the surface of the mold may not be that even. Do you have any plaster left to do another one? I wondered if the plaster was old. I've found that if I use old plaster that has absorbed moisture in the container, it can sometimes get bubbles.

[@mottspoint]

Clarity on the "plaster islands": are those "islands forming" because the plaster added to the water is approaching the water level? And do the islands stay there or form and go under? Thanks for this video which is the easiest one to follow. And PS, I did two in metal bowls: it takes a little to get them out. I used a rubber mallet with a folded towel protecting the metal, and in the case of a large one, did a couple of drops from two feet onto a folded towel on a hard surface. I used a Burt's Bees hand salve of wax and botanical oil for the release as I didn't have vaseline.

[@ThePotteryWheel]

Hi Jennifer, the islands form when you are getting to the point where you've added enough plaster. It starts to poke out of the surface of the water. Islands tend to stay there rather than crumble. Once they appear it's a good idea to start mixing quite soon before the plaster starts to harden. Good idea to use Burts Bees!

[@sistercookies]

Would you shave the edges of the foot of the finished plaster bowl so that it was completely rounded? Aren’t most hump molds rounded? I’m guessing it’s just personal choice. Thanks!

[@MrsSceptical]

Thank you! a wonderful 'how to', can I ask how long you let the plaster set in the bowl before turning it out ?

[@ThePotteryWheel]

I'd leave it a few days. If you turn it out too soon, the plaster is still soft and 'cheesy' and might crumble

[@moonchildceramic]

Where can I buy this plaster? Thanks for your help

[@ThePotteryWheel]

Hi Kathy, what country do you live in? That will make a difference in terms of where to buy your plaster. You can use plaster of Paris or pottery plaster. If you want to know a bit about the difference between the two, you can have a look at this thepotterywheel.com/pottery-plaster-vs-plaster-of-paris/

[@moonchildceramic]

@@ThePotteryWheel hello thank you! I live in the United States

[@ThePotteryWheel]

@@moonchildceramic Hi Kathy, check out this article, it has links to where you can buy the plaster and some info about what kind of plaster to use, hope it helps! thepotterywheel.com/pottery-plaster-vs-plaster-of-paris/

[@donnajobe6111]

I followed your instructions to a T! I cannot get mine out

[@ThePotteryWheel]

oh no! Did you use a slightly flexible bowl? If you use a rigid bowl it will be hard to get the mold out. But with a flexible plastic bowl you can give it a bit of a wiggle, and the mold should pop out.

[@svetlanabalashova9027]

Could have been a 5 minute video.

[@amyshimm]

I respectfully disagree. Lesley included many important details to ensure the mold is made properly, from what type of mold bowl to use, to how to mix the plaster, and even where to discard the cleaning water from the bucket. You can always speed up the video, skip ahead or find another resource if this doesn't suit your needs.

[@thevagabondonwheels4918]

In the KZbin settings, there is a playback speed option. Change it to 2x and voila, a 5 minute video. However, considering that her channel is one of the most helpful pottery-related resources on the Internet, I disagree with your assessment.