Casting Experimentation Sub-Phase 4

Alas Poor Clay Foot

This blog will be a two part discussion of the mother mold created for the clay foot and latex mold and of the subsequent casting of the first test foot (TF1) using the aforementioned latex mold.

The latex ended up staying on the clay foot model for approximately 36 hours. Normally I wouldn't leave it in place that long but I had better things to do. After running out of better things to do I set about prepping the clay foot and latex mold to create a mother mold. The mother mold is a second mold created over the existing mold, and serves as a support to the latex during the casting process.

(Clay foot and latex mold before the mother shows up.)

Before I go any further I will say this isn't the end all be all of copying models or casts. It's just a method that I've found works well for me (so all you modeling and casting nerds can stick it before you get riled up).

The first part of the process in making the mother mold is locating a trash bag. I like to use the heavy duty lawn bags. Take the bottom of the bag and smooth it out over the surface of the latex mold. Where spaces like in between toes are concerned you want to make sure the bag goes between them but not to the point of being form fitting. That extra little bit of space will be necessary for extracting the model from the mother mold. Too close a fit and the mother mold and model will lock together.

(Thus the bag is applied to the model.)

Once the bag is applied over the surface of the model you need a box. The box should be roughly the same size as the model while leaving a little room around the edges. It also needs to be deeper than the model. Cut open the bottom of the box and pull the trash bag up through it, while leaving the bag firmly impressed over the model.

(Thus the box is applied to the bag which is applied to the model.)

That's it for prep. At this point the only thing left is to mix up enough plaster of paris (PoP) to completely fill the box up to the point that the model is completely submerged.

(Thus the PoP is applied to the box that was applied to the bag that was applied to the model.)

The only thing left to do now is sit back and wait. Time allowed varies depending on how much PoP was neccesary. I managed to keep myself occupied for about three hours. In any case it's important to allow enough time for the plaster to fully set.

(This killing time is killing me.)

Once the plaster is set you simply lift up the whole package (box, mother mold, bag, latex mold and model) and gently turn them over and remove in the opposite order. Depending on how good a job you did smoothing out the bag it will or won't have bound in folds of the plaster. Just gently tear it away.

(Cracks kill.)

Unfortunately as the above photo illustrates my clay foot had some serious structure related deficiencies on the underside. Since it was only ever intended to be a model for the creation of TF1 I only shed a few tears as it crumbled out of the latex mold.

With the now defunct clay foot disposed off the latex was peeled away from the mother mold and the bag was removed as well. There was a considerable amount of adhesion between the surface seal of the clay foot and the latex mold despite the release agent used. In the past when making latex molds of sasquatch casts I've always applied the latex directly to the untreated cast with only a release agent, which leads me to believe it was the sealer that created the problem Regardless of this for the creation of TF1 it's a moot point since it will be sanded prior to being used.

(A little dust is all that remains of poor clay foot.)

(The mother mold in all its glory.)
(Then they form up like Voltron.)

With the mother mold now made and the latex mold cleaned up and ready to go the only thing left is to use them. Since TF1 needs to be durable enough for multiple uses I dipped into my stash of Ultracal 30.

(The genesis of TF1 begins.)

The Ultracal 30 was mixed per the manufacturer's instruction. Once the slurry was properly prepared it was poured directly into the latex mold.

(The genesis continues.)

With the latex mold fully filled the next step can be accomplished. In the past I've embedded hangers into the back of the cast so that it could be displayed on the wall. Since TF1 will be used for test casts this wasn't neccessary. However, I did want an easy way to pull the cast out of the casting substrate so I decided to include a couple of handles in the back.

(Handle making Step 1.)
(Handle making Step 2.)
(Handle making Step 3.)
(Handles.)

Inserting the handles is a bit of a trick. The slurry needs to be soft enough so that the handles can be inserted but not so soft that they sink to the bottom. The bent ends of the handles are inserted into the back of the cast until they're fully submerged. The slurry is then smoothed back over the hole created by inserting them.

(Handles inserted.)

With the handles set into the back of the cast there's nothing else to do but wait. Again, proper time needs to be allowed for the cast to fully set. Once the cast has fully set the last step is to simply remove it from the mother mold and peel away the latex.

(TF1 is born.)

And that's about all there is to it. From clay model I've made the transition to gypsum cement cast. In the next and final installment of the sub-phase I'll be preparing the surface of TF1 for the subsequent casting experiments.

Casting Experimentation Sub-Phase 3

Fun With Latex

With the clay model made and properly prepped it was time to move on to the next phase of the process. If you've never made a latex mold you'll enjoy this section. In fact, if you have a few sasquatch casts laying around this can be a great technique for making copies. Then you can swap and trade casts with your friends just like collectible cards. Or sell them on E-bay. Whatever.

The first step is to prep the model with a release agent. Since I didn't want to leave the house and drop some dough on a real release agent I decided to MacGyver it. So off to the pantry I went for some Best Choice Pan Coat™ (aka ghetto PAM).

After testing to see if the Pan Coat was flammable (it is) a thorough coating was applied to the clay model.

(Nothing says scientific like generic pan coating.)
(A thorough coating of Best Choice Pan Coat means you'll never scrape another pan.)

Once the clay model was coated with pan coating the excess liquid was removed with a dry paper towel (also generic).

(Don't forget to dry between your toes.)

Once the extra coating was removed it was time for the latex. My personal preference is Mold Builder liquid latex by Castin' Craft™. You'll also need a paint brush to apply the latex. Be sure to prep the brush and make sure any loose fibers are removed or else they'll end up embedded in your mold.

The mold is created by applying multiple layers of liquid latex to the model. Each layer should fully cover the model and be given adequate time to dry before applying the next layer. The evenness of each layer isn't critical but if you apply too much in one area it will take longer to dry. From personal experience I like to make the first couple of layers extra thin, with subsequent layers being thicker.

(Diving in with the first layer.)
(The latex is applied thinly enough that you can still see the surface color of the model.)

Once the first layer is applied it was time to sit back and wait. If the latex is applied thinly enough it shouldn't take more than about 30 minutes before you can apply the next layer. As the latex dries the color changes from white to an off-yellowish color. The below photo was taken in between the application of subsequent layers. The areas that are white are still wet and need additional time to dry.

(If it's white it ain't yet right.)

This is as good a place as any to point out that between coatings you need to thoroughly clean your paint brush. Warm water will work just fine but you need to be sure to remove all the water before applying the next coat.

With each subsequent layer you can increase the thickness of the latex applied but you'll need to allow an increased amount of time for drying. Since the last two layers I applied were especially thick I allowed an hour between coats. The fact that the latex changes colors makes it easy to tell when it's ready for another layer.

(If this were a real foot I bet that would tickle.)

That's about it. The total number of layers is flexible but you want to make sure you apply enough layers to prevent the mold from ripping or wearing thin. For this model I used a total of seven layers with the 6th and 7th layers being extra thick.

(The finished product.)

Once the liquid latex application is complete the latex needs adequate time to dry completely. Since I'll be creating a mother mold over the model (with the latex still in place) I'll just leave the latex where it is until I'm ready for the next step.. If you need to remove the latex from the model prior to creating a mother mold (or if you're not bothering with a mother mold) I'd allow 24 hours before removing.

That's it kiddies. The next installment will be a mother.

Casting Experimentation Sub-Phase 2

Truth in Advertising

The creation of the test foot continues. After the clay model was completed it was allowed to air dry for five days. You may ask yourself how it is that the model air dried for five days yet the blog documenting the second phase of the process is less than 24 hours after the first? You ever see on of those cooking shows? One second they're prepping their main course and sliding it in the oven and then the next minute they're pulling out that pot roast that takes two hours to cook. It's something like that.
After drying for five days there was a small but noticeable amount of contraction in the model. While it was expected and while it will have no impact on the eventual product I did feel a few photos of the shrinkage were in order.

(The amount of contraction is evident in the clean outline on the pan surrounding the foot.)

In order to move on to the next step of the test foot creation the model needed some additional preparation. Specifically it needed to be sealed. For this purpose I turned to the good people at Krylon™.

(Don't believe the hype. Low odor just means it will take longer to stink up the house.)

Because of the clay's natural tendency to absorb moisture and due to the fact that a wet latex will be used in the second step of this process the surface of the clay needed to be sealed. The sealant was applied to the model per the manufacturer's suggested method of application. Two coats were applied to the model.

(The sealed model.)

After sealing (and after airing out the house) a few additional documentation photos were taken.

With the clay fully dried and properly sealed the modeling phase of the process is completed. Subsequent stages of the project will involve creating a latex mold of the model and then the actual creation of the test foot.

Casting Experimentation Sub-Phase 1

Something Is Afoot

I decided not long ago that it was time to contribute something new to this field. What better an area to contribute I thought than to a subject not only familiar to myself but to one that has been unjustly maligned despite its significant importance. This subject I speak of is casting artifacts.
Before I can begin however I need to pay homage to those who have laid the ground work before me. Were it not for the intrepid work of people like Matt Crowley and those that diligently and without bias replicated his work I would be stumbling through the dark here. In fact, had it not been for these fine gentleman the issue of casting artifacts and their importance to research regarding alleged sasquatch casts might not even be taking place today.
Now everyone knows you need a print in order to make a cast. In order to make a print you need a suitable object with which to make the print. Seeing as how the subject of casting artifacts here deals directly with their implications in regards to alleged sasquatch tracks I thought what better an object to use than a foot.
Since I couldn't just go out and buy a foot suitable for my needs I was left with no option than to create a foot of my own. This post and the subsequent ones in the "Sub-Phase" will deal exclusively with the foot creation itself.

Preparation
The first stage of the foot creation was to create a suitable model. I chose to use pottery clay for this stage. Clay is inexpensive and a much easier medium to work with than wood. Since the clay would only be used as a model the potential structural brittleness of the dried clay would be a non-issue.

(Getting started; Pottery clay and tools, baking pan, and a cameo from the Elkins Creek Cast.)

Unfortunately for me the "moist" pottery clay I purchased came out of the box resembling a gray brick. After attempting to shave off the hard outer surface I finally had to resort to re-hydrating the clay in a plastic bag with water.

(The clay itself after re-hydration.)

Once the clay was properly re-hydrated the modeling began. At this point it would have been easy to just create a flat, generic foot shape. Easy was not what I wanted. I wanted the eventual test foot created from the model to create an impression that would closely mimic those attributed to sasquatch. To that end I tried to shape the foot to be a realistic three dimensional representation of the classic archetypal sasquatch foot, or at the very least the print left behind by the foot.
Special care was taken to include features that would produce a print that replicated the dynamic application of force from a living foot striking the ground. The toes are modeled in various stages of curling representing the foot pushing off from the ground. The ball and heel were sculpted to rise above the general surface of the foot to represent the initial and secondary weight placement of the foot over the course of the step. The midsection of the sole was likewise sculpted in a gentle arch to further represent the transfer of weight.

(A foot is born.)

After shaping the foot was structurally sound but still needed work. The surface of the foot needed to be smoothed in preparation for the later stages of the project. This was achieved by applying water directly to the surface of the clay and smoothing by hand, then with a sponge.

(Smoothing the cast. Latex gloves were used to prevent imparting any incidental ridges to the surface of the model.)

(Final smoothing of the model via sponge.)

The following photos are of the finished clay model.

(Surface detail remaining on the model. This will be dealt with in a later stage of the process.)

Something Is Afoot

After a long hiatus from posting here I've decided to rededicate the Possum to new endeavors. Please enjoy and feel free to provide any feedback. Thanks.