Monday, May 14, 2007

Making Kagura part 4: Waste mold revisited


The fourth installment of this figure-making-guide is here. In this installment, I'll be showing you how to make a waste mold for our oil clay figure and cast it in paper clay or polyputty. I have written a guide concerning the production of waste mold here, but this time I'm going to show another way to doing just that.

Well, lets get started shall we?

The main reason we're making a waste mold is to cast our sculpture in a stronger media. Let's face it, oil clay is great to work and sculpt, but a slight slip up can destroy a full day of work in an instant. Accidentally pushing your sculpt off the work desk is one of those slip up. Before that happen (and you loose your insanity, not to mention your hair), we're going to cast our oil clay Kagura in paper clay and pollyputty. Click the picture to enlarge.

I've developed this method of making waste mold while trying different stuff to achieve the same result. I found this method easier and faster in producing a waste mold. If you have a better way in doing this, do share it with us!

Let's get the figure ready first. I scribe a line on the side of the body and leg. This line will be our seam or parting line, the line where the two (or more) part of the mold connects. If you dont have a clue on making this line, just grab a toy and observe the seam lines on it. Then, using a cutter blade, I cut deeper into the lines, being carefull not to go too deep and split the figure. Next I put paper strips in the lines. The paper will act as a barrier for the mold parts. Take your time while doing this, make sure the papers are secured on the clay. After the paper are secured, brush some vaseline on the entire surface of the figure. This will act as a mold release agent, and it'll make the clay surface smoothe like a baby's tushie. When that's done, we're ready to make our mold! JOY!

Okay, let's get the materials next. I use polyputty, laquer thinner, vaseline, toothpicks for stirring the putty and some cardboard for mixing the putty. You can see the other stuff I use in the picture below. Easy no?

Mix enough of the putty and the hardener on a piece of cardboard. Why on a cardboard you asked? So you can throw it away when you're done. Easy cleanup ^_^ After getting the putty all mixed up, thin the mixture with laquer thinner. The aim is to get the mixture thin enough to be easily spread on the figure WITHOUT forming air bubbles. Dont worry if you add too much thinner, as long as you got the putty-hardener ratio right, the mixture will harden (although I might be wrong on this -_-u). Spread the mixture evenly on one surface of the figure and paper. Make sure all the surface are coated. Add more if you think it's to thin, especially in parts that sticks out (boobies for example). Let it cure for a while, and then flip it over and do the same on the other side. Let the polyputty fully cured. We have our waste mold!

This is the difficult part, more difficult if you forgot to add vaseline beforehand. Pry the mold open GENTLY! If you did the steps I said above this shouldn't be too hard. The oil clay figure WILL be destroyed at the end of this process. Remove any clay that still cling to the mold. Lighter fluid and cotton swabs helps. After you get the mold clean, it's time to coat the inside of the mold with vaseline. Make sure you got all the nooks and cranies coated. Our mold is ready to use!

Here I'm casting a paper clay copy using the mold we just made. I'm using the arm part of the mold. Just fill one half of the mold with paper clay. It's okay to overfill the mold, but not too much. Press the two halves together untill the clay leaks out. Trim the clay. Open the mold and you have yourself a copy of the arm. Let the clay dry and continue with your sculpt.

Here I cast two copies of Kagura's body, the yellow one with pollyputty, and the white one with paper clay. The mold broke after I cast the pollyputty copy.

That's the end of the 4th tutorial. I hope you enjoy reading it.

I dont have any plans for the next installment yet. But I'll think of something.

Until then!


Omar said...

Hey MIDZ, thanks for telling me about molds from the other post. I found this very useful! ^^;
Also, did you make the polyputty mold out of the waste mold of the same material? It didn't dry IN to the wastemold?

Oh and which is better for sculpting out of( and lasting longer) , polyputty or paperclay?

Thanks again!

MidZ said...

Hey Omar,

Yes, The waste mold and the polly putty cast was from the same material. Polyester putty better known as automotive putty.

The key for easy release is Mold release. Just brush some paste wax inside your waste mold before you fill it with more putty. The cast will be easy to de-mold. This method can also be used when casting resin with a plaster mold.

As for which one last longer, I'd say the polyputty wins. It's harder and sturdier than most paperclay, and it's cheap to boot. It's pretty hazardous though, but as long as you wear the proper safety gear, I believe you'll be fine.

Good luck!