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February 6, 2009

Article 4 Casting: VolAsh/Pumice

As you seen in the articles posted thus far (in reference to my casting) I have yet to replicate "artifacts". As you will now see, that has changed.

Sometimes in life,

when your trying to solve a mystery, you can really think too hard. You can get bogged down in details and facts, that mean nothing to the work your doing. While I was concerned with the Pumice, I forgot how very important it is to not be distracted by "issues" that mean nothing to the overall end result.

Investigating what this VolAsh/Pumice really is, was very important to the work ahead of me. I needed to know just how fine this product would be. That question was answered by not only CR Minerals, but by myself as I touched and felt this specific product. Why is this important? It is my firm belief "artifacts" will only happen in substrates which are of a small grain size. Why is that? Well, if you have been following my work to date, you will know I was able to cast my own dermal ridges in the Onion Mountain Soil sent to me. I was not able to create "artifacts". It is my opinion, that is due to the grain size of the substrate being larger, and not as easily moved by the casting agent. But, I would not know for sure, until I was able to create artifacts.

I received my bag of Pumice,

and I immediately went to work. I was casting until the early morning hours, doing everything I could think of.. Water Temperature was 100 degrees, using my hand (with a latex glove) to mix the casting agent. I mixed the casting agent to the consistency of pancake batter, and pouring straight into control casts. 5 casts, and nothing.

I was (to say the least) frustrated.

Sometimes it's ok to take a break and just relax. I needed to do that. I was very angry and frustrated that I was not able to replicate "artifacts". This was supposed to be so easy. Why was this not happening? I took a few days to relax. Then I decided to go back to the beginning. I spoke with a few friends, and it was during one of these conversations I had an epiphany.

In my very first articles, do you remember what I was told by the gentleman with USGypsum.com? How air bubbles can have such a horrible effect on casting?

I then decided to go back and read everything, and I mean everything. When all the sudden, I had a realization that (in all honesty) was so obvious, it actually made my head hurt. I could not wait to get home after work and pour my next cast.

As you can see in this photo, I have been able to create artifacts.

Now, I will tell you how I did it.






Water Temperature: 100 degrees
Casting Agent: 1 1/4th cup
Water 2 cups
Wood Spoon used for mixing

As I went back and re-read all those old posts, one item kept popping out at me, "Chopsticks". I never really gave it any thought. I just figured chopsticks was that persons preferred method of stirring the casting agent. As it turns out, the chopsticks are key to creating artifacts.

Why is that?

I'm glad you asked. Think about cooking. When you use a wire whisk, you are incorporating air into whatever you are mixing. Take Whipping Cream for example. Without the introduction of air, you would not have that fluffy light consistency that is desired. This is due to the introduction of air during mixing.

Air, by the way, is one of the worst things you can introduce into your casting agent during mixing. When I mixed the first batch of casting agent, I used the spoon portion of a wooden spoon (I had no chopsticks on hand) and I mixed it fast. The amount of air I had introduced could be visualized by looking at the top of the casting agent in the bucket - they were visible as hundreds of little dark spots on the top. I noticed this, because I had not seen the top of the casting agent look like this.

But now here is the interesting part.

Water Temperature: Room Temperature 75 degrees
Casting Agent: 1 Cup
Water: 2 cups
Wooden spoon handle used for mixing

As you can see in this photo, using the Manufacturers specs for the amount of casting agent, and water just as I had done roughly 70 times prior, had created "artifacts".

The difference this time?

I used the handle of a wooden spoon. Using the handle of the same wooden spoon was narrow enough in width to introduce enough air to create "artifacts". I was able to create "artifacts" also while pouring straight into the track, or multiple pours.

Changing the direction of the pour (after initial contact with the substrate) did create more pronounced "artifacts", which I find interesting.

I did go back and try this on some of the remaining soil I have from Onion Mountain. Using this method I was unable to produce "artifacts". Why? It is my contention the soil grain size in this area is too large to be affected by the air bubbles in the casting agent. Grain size of the substrate is very important. It is also my contention the mineral type has nothing to do with the production of "artifacts". If the mineral in question is of a small enough grain size and dry, it may in fact produce "artifacts". I have no reason to doubt the information given to me by the same person with USGypsum.com, that the mineral type has no effect on the casting agent.

It has been said,

due to the large amount of forest cover (leaves, pine needles etc) in the Onion Mountain Soil that was sent to myself and another researcher, "artifacts" are not possible. I would respond by saying, I am pretty sure there has always been pine trees, leaves and other forest cover in this area, it is a forest.. I would imagine if I could jump in a time machine and go back to the day the Onion Mountain Cast was collected, and took a sample of the soil then, it would have the same type of forest cover "contamination" contained in the soil.

So, the information I received from the nice man with USGypsum.com was correct. Air is not your friend. You should not mix your casting agent with anything smaller in width, than your hand. He recommends your hand with a latex glove, or a paddle (you remember the paddle ball game, just remove the ball it will work fine).

We must avoid the introduction of air in the mixing of the casting agent.

Tapping the sides of your bucket will also help release the trapped air in your mixed casting agent (but not all, so be careful during the mixing process). Remember to add the casting agent to the water, slowly sprinkle it in. Doing this allows the water to "take in" the casting agent thereby releasing trapped air within the casting agent. Do not begin mixing until all of the casting agent has been added to the water. You will actually see the trapped air come to the top of your bucket as an air bubble.

Chopsticks or wooden spoons used to mix casting material, do not rock.

There are some in this field of research who have a habit of doubting what is said to them by people who have advanced knowledge in various areas, germain to our research. In this specific situation, had I payed more attention to the expert with USGypsum.com, this may not have gone on so long. Instead I allowed myself to be bogged down in arguments over water temperature and pancake batter. I should not have doubted this man from USGypsum.com's 25 years of experience with this product he has such an incredible knowledge of. We really should listen to those who have expertise in areas, especially when that expertise or knowledge can help us.

It should also be noted. No one (to date) has been able to reproduce "artifacts" in a wet substrate (mud). So far it would appear the substrate must be dry in order to produce "artifacts"

Heeding these warnings is so very important, and can help you feel more confident in the outcome of your field casts. In the end, isn't that what matters?




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