Making Damp Boxes for Ceramics and Pottery from Plaster and a Plastic Bin

A damp box may soon be one of your favorite tools in the ceramics studio. It is a box with a slab of dampened plaster which allows you to store your pieces in progress and keep them damp for an indefinite amount of time. One of the tricks for any potter is keeping the different pieces of clay the same moisture until attachment, and a damp box is a wonderful means of keeping them the same moisture and workable.

In this video, I show how to ADD new plaster to OLD plaster - as I already had a bit of plaster in the bin to which I wanted to add more. I roughened up the surface to prep for the addition of the new plaster. This should be done really as soon as the first plaster has begun to cure. (If you would like to see the video on how I made the plaster HUMP molds, it is here:

Because I use plaster in the video, I should have mentioned how careful you should be when working with plaster in a clay studio. You never want to inadvertently get plaster in your clay!

I ready my area by covering my table surface to protect it, I have a bucket double lined with plastic bags taped to it, water already measured to reach about ⅔ of the bucket, paper towels, gloves *which I taped additional plastic to lengthen them on my arms… and a dust mask or respirator and a trash can close at hand.

I use COLD water in my bucket, and begin by slowly sprinkling the plaster over the surface of the water. Continue until you have sprinkled enough plaster that it makes a little “mountain” which doesn’t go under the surface. When you have reached the mountain stage, begin a gentle mix without incorporating air. Gently mix with your fingers, and break up any bits which form. Keep an active mixing going the whole time. I find it takes about 15 minutes of mixing for the plaster to be ready to pour. You want to be patient, to make sure it will be starting the process of curing so it will stay in suspension. Pouring it too early can result in a weak plaster and water migrating to the top. Don’t use warm or hot water, as although it will speed the curing, it will also encourage chunks to develop.

In the video, I waited about two hours for the pieces to cure before cleaning it with a scrubber and sponge.

Check out my Amazon Influencer Store where I have recommendations for some of my favorite tools and products many of which I use in my videos- which are available on Amazon.

Check out this link to a live Googledoc I continually update with lots of my favorite tools on Amazon using my associate links! (also some non-amazon suggestions on here!)


I am a public high school ceramics teacher at William Mason High School in Mason, Ohio. (Mason is currently the largest high school in Ohio!) As a potter, I have been working in clay for over 30 years, and I have been teaching for over 28 years, the past 20 have been specifically teaching high school ceramics. I love what I do! I have my own studio in my home basement, where I work on my personal pottery for my Etsy site;

I started my Youtube channel to make videos to help my students if they are absent and miss a demo, or if they would like to explore more advanced techniques independently. I have been amazed to reach such a wider audience than my own students!

Please subscribe to my channel if you would like to receive channel updates, or would like to learn more about clay and studio processes!

Plaster,pottery,ceramics,damp,box,bin,leatherhard,plastic,mix,mixing,working,work,cure,set,Pottery plaster #1,#1,best,video,potter,studio,tool,tools,moist,control,moisture,handles,handle,cup,cups,water,pour,mold,prep,prepare,demo,demonstration,show,how to,how,teach,class,classroom,studios,student,students,teacher,high school,mason,karan,witham,walsh,wet,wetness,humid,combining,adding,repour,