April 3, 2006

My First Cast

Well. I always talk about the work of other researchers and never my own... That's pretty much the way I like it - lmao.

I had a brainstorm the other day - I had never done a Track Cast, and who knows when I will ever get a chance to - lets face it, evidence of this animal is hard to find and the animal even more difficult to come across.. So, how do we practice and get good at making Track Casts?

We get our own feet dirty :)

Sunday I decided to turn off my computer, and run out to my local Home Depot( across the street ), Where I purchased Plaster of Paris, 2 - 2.5 quart buckets, latex gloves, and a good tape measure. I also picked up 2 rolls of hot pink tape - as it will be great to have in the field to mark my finds, or a trail.

Ok, so I took my supplies and headed down to the little creek that flows just below my apartment complex. I had a volunteer step into the moist soil near the creek( with their shoes removed ). I then thanked the person and asked their foot size - 10 1/2, you didn't think I would use my own foot!! :)

It should be noted, before trying any of this, I read and re-read the blogs by Rick Noll on Casting Tracks. I took notes and paid close attention to what he did, as he has great success - so why try to reinvent the wheel?

I dug out around the footprint - creating a "trench" if you will. I then marked off the area around the footprint with my hot pink tape - so I wouldn't step on it and ruin the print before pouring my plaster of paris. I then grabbed one of the 2.5 quart buckets and filled it with water from the creek, being careful to remove any leaves, twigs, etc. I then grabbed the 2nd 2.5 quart bucket and with my dry hand, I put in about 3 hand fulls of the plaster of paris, then slowly added water..

First Mistake: Put the Plaster of Paris into the water - pouring the water over the dry plaster of paris just makes clumps. I knew this before hand - and in my excitement to get to the finished product, I forgot. All was not lost, it just took a little longer to get all the lumps out.

It was decided in the beginning I would do 3 "pours" - the first being a thin mixture, the second being a little thicker, the 3rd being the thickest. Turns out, my volunteer didn't step deep enough or the soil just wouldn't allow the foot to sink in deep enough - or I filled too much for the first splash coat - lmao.

I cleaned out my bucket holding the plaster of paris mixture after the first splash coat - and waited for it to set, being careful to not let it sit too long before the 2nd splash. The second coat was applied approximately 15 mins later, being very careful to get around the edges outside the track cast and not get any sand into the plaster of paris.

Second Mistake: I didn't figure the moisture of the soil into the mixing of my Plaster of Paris.. All was not lost - it took a little longer for the plaster of paris to set up enough to start pulling away the outer edges, but it did not affect the final outcome.

Texas Soil is very sandy and has a lot of clay in it. This I discovered while digging the "trench". As I scraped the soil off my knife - I could feel the clay, I was surprised by that. I expected the sand but not the clay.

Why didn't I use Hydrocal? Well, I must find a store that sells it first. Second, this was practice, and I wasn't to concerned about needing hydrocal for practice. The measurements in this are not precise - I tried to get measurements, but I think its a matter of feel.. Also, its hard to take measurements on this for a 10 1/2 and translate those to a possible track of 12 or even larger, at least for me, as I hate math.

After letting the plaster of paris sit for about a half hour or maybe around 35 mins, I began to slowly pull the sand from the outer edges, being very careful to only take away what would fall freely. This is a very time consuming task, but the outcome would be worth it.

After pulling the cast from the ground - I took it back into my apartment where I put it in an old baking dish - and put it in my oven, set the temp to 200 degrees, where it cooked for about 2 hours. I then pulled it out of the oven and began the task of clearing away the sand that was remaining.

Here is the finished product - or as good as its going to get for now. :) Im happy with my very first attempt.. Practice, Practice, Practice. :)

And, Yes, I know I need to work on my Picture taking skills too :)


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