Casting Your Fast Faces in Cement


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cast concrete fast face with rebound 25

Using Rebound 25 and Thi-Vex to Make a Small Concrete Casting

I created a new Fast Face this week. This time it turned into a slightly grumpy bulldog. If you’ve had a chance to read my new book you know I made my little bulldog by following suggestions I found in a lump of clay. The part of his face that I didn’t change at all was the mouth and muzzle. There was a suggestion of a nose on the clay, but it was a triangle, so I gave him a dog nose instead. There were lumps for ears, but I moved them around. The ears were made quite thick because concrete doesn’t work well for really thin, delicate forms.

Rex told me he’d like to make some Fast Faces to put out in the garden, and I think that’s a great idea. The molds are a little expensive for just one casting, but when your neighbors see them they’ll probably want some, too. Making duplicates will only take a few minutes because you already have the mold, and the new casting will cost about a nickel. The castings can be painted with acrylic or latex paint, but I really like the natural color of concrete.

Plaster of Paris is easier to use than concrete, but you can’t leave a plaster sculpture outside. When you go to the DIY store for your cement, tell the clerk you’d like a product that contains Portland cement and can be used in a mold. If you get a blank look, mention stepping stones. As I mentioned in the video, I lost the label for the brand of cement I used for my bulldog, but the brand doesn’t really matter.

It would be nice to use a product that sets up faster, though. That way, if the first one doesn’t come out quite right you can make another one without spending so much time waiting for the cement to get hard. One brand that sets faster is Quikrete. You can find it at most Lowes and Home Depot stores here in the US. A 50 pound bag costs about $5, and that will make a lot of castings. The silicone is expensive, but both cement and plaster are really cheap.

The Smooth-On website has tutorials for the Rebound 25 brushable silicone mold material here. I didn’t follow all their instructions because I wanted to save money.

If you’d prefer to purchase the Rebound 25 and Thi-Vex from Amazon instead of directly from the Smooth-On company, you can find them here.

Enjoy!

14 thoughts on “Casting Your Fast Faces in Cement

  1. Hi jonni

    I received your”Fast Faces” book yesterday and it’s a great book. There were three things that were especially helpful for me. The first was that great sculpting stand that you should us how to make. So simple but still so useful. I can’t believe the way I was sculpting before. My sculpts turned out well but I sure was making things hard for myself. Than the short part where you touch on using silicone to make molds. I have been making silicone molds for years but the way you use the clay, and the clay you use, will be big benefit for me. I used to use a very soft Plasticine clay which allowed for the spontaneity but when I started to make silicone molds from my sculpts I went to the harder Plasticine clays which, in a very short time, became tedious and a lot less fun.
    Now by using the clay you suggest and letting it harden by itself a little bit I can make my silicone molds without having to struggle with the harder tedious clays and worrying about brushing out the detail..
    It’s strange how a person can get bogged down with the technical aspects of sculpting and lose sight of the fun of just doing it. Thanks for the important information and thanks for the fun.

    • Bruce, thank you so much for letting me know that you received the book and that you find it helpful. Your comments really mean a lot to me. I know it was a lot of fun to write because I had a good excuse to play with the clay. And I agree about the way the harder oil-based clays slow you down (and perhaps even make us think too much before moving it around). That’s great if you have everything planned out ahead of time in great detail, but if you’re just searching for a new shape or expression, they can be tiring.

  2. Hi Jonni

    I ordered your book on “Fast Faces” and am excited to get it. It should arrive tomorrow. I was reading this discussion on making cement sculptures and it brought up an idea that has been coming up in my mind every now and than but I have yet to follow through on it. I used to make latex molds and cast concrete in them. but what a hassle. than on the other hand silicone rubber is so expensive especially if you only want to make one copy. There are quite a few melt able and reusable casting materials but they are still too expensive for the size that I would need and are still a big hassle to use. I want to, some day, make some large gargoyle statues.
    Anyway to get to the point i wonder what you think of the idea of first sculpting the gargoyle out of Wed Clay than painting on a plaster shell around it. Than take out the Wed Clay and than pouring the concrete. The thing is , concrete needs water to cure so you keep the plaster wet. Since plaster hates water, [once it sets up], the plaster will disintegrate as the cement hardens. Or you could just set the whole thing outside and watch nature take its course. Have the fun of watching you sculpture reveal itself more each day. Like something hatching out of an egg. LOL I once watched a contractor make a decorative concrete wall. The mold was some sort of plaster and than they poured the cement wall. After a week or so they just sand blasted off the plaster revealing the cement sculpture. I have also read about some chemicals that disintegrate plaster and maybe they wouldn’t harm the cement. Anyway I would love to hear your opinion on this or maybe some one has already tried this?

    • Hi Bruce. This is an interesting idea. If the plaster shell was quite thin, and supported somehow to take the weight of the concrete, it certainly could work. No guarantees, of course. Your comment reminded me of the plaster waste molds I’ve seen, where the plaster is chipped away from the finished sculpt. They must have a way to keep the plaster and concrete from bonding with each other, and you might be able to use parts of that technique, along with your idea. If you do try this, please let us know. I’d love to make some cast concrete yard sculptures, but the cost of a silicone mold of any size for just one sculpture is way too expensive for me. If your way of doing it works, that could open up a lot of possibilities.

  3. Can you mix it thinly, so it works well in a mold? Or do you use it for hand-sculpting? If you’ve made anything with it, we’d love to see how it came out.

  4. I finally received your book and read it tonight. Fabulous, just fabulous! I loved all your thoughts on talent and creativity, which totally concur with mine but you were able to put it into words. Maybe that’s why you are the writer and I am not! I have a rule in my classes that no one is to be critical of their art, which of course they tease me about(but secretly appreciate) I may just utilize your fast faces for a new class…but first I have to try it. I just bought the wed clay so when that arrives, I will do your 30 day challenge and decide if I can teach it. It opens up a whole new dimension to approaching art, so positive and as you said in your book, healing.
    Thanks for the tutorial on casting. I don’t know if I will do it but it is good to have to refer to if I ever do want to do it.

    • Hi Eileen.I’m so glad your book finally showed up. The guys at UPS must have been scrambling after your two storms!

      And now I can’t wait to see if you hold that class, and how it works out if you do. A community art teacher in North Carolina, who teaches ceramic sculpture, is also thinking about trying it in a class. I’d really like to know if the concept is easy to share with people in a group. You should be able to tell how well it will work after you made a few Fast Faces of your own – please let us know what you think.

  5. I ordered your Fast Faces book. I bought some WED clay.Lots of fun. I will try casting in concrete using the Smooth On for a mold.I like the idea of sculptures that can be kept outside.

  6. I am excited to try this. (Does anyone want to tend a dog for a month? These triple walks a day and then resting takes a lot of time. I love her so much, and she really keeps me going.) I got everything I need. I even have a bag of Quikrete that I stole from my sister, so all I need is a little discipline.

    I’m working on 6 fish and another project right now, so I’m on two or three time schedules.

    Thanks so much, Jonni. You make life so much more fun.

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