Hello again, Dendroboard!
Recently, I had a chance to go through my parents' wooded property, about 5 acres of which is wooded and overgrown with undergrowth. I was going mostly for inspiration, trying to find a setting for a terrarium, or part of a terrarium.
I took a LOT of photographs of very nice things, but I became enamored with one photo:
It hadn't looked as impressive when I took the photograph. But when I looked back at the photographs I had taken later, I could see a very attractive stump with many grooves and recesses fit to grow plants in.
Obviously, a rotten stump fixed in the ground isn't the best option for a terrarium, but I had read recently about the process of artificially converting wood into driftwood, and thought I would give it a shot.
So, the next day I set out with a yardstick to ascertain the dimensions ... and I found that it was much larger than I had remembered. It was about 36" off of the ground, and about 24" wide and 24" deep. Nor could I just cut off part of the top and convert that to driftwood; the flared out base was what made it a stump, and made the spiky top parts that spread out seem more significant. And even if I cut it off, I would have to risk it undergoing the driftwood-conversion process, which may well not work on partially-rotted wood.
Instead, I decided to make a foam model of the stump. I had read and watched tutorials on how to do this, in more than one way. I had many times over the supplies to make a foam stump. So I took a bunch of photos, printed them for quick reference, and set off.
This is the agent that I will be working with to cover the surface of the foam prop once it is done. Drylok is no stranger to vivarists. Mostly I'll be using it to add texture to the EPS foam, because straight painting acrylics on top of it wouldn't make it look too stump-like. It is somewhat expensive, though.
These are the most important tools for the foam, and probably for the entire project. They come from Hot Wire Foam Factory, a business well known among model-makers. If you aren't familiar with these tools, they heat up a narrow metal wire by using a power station plugged into the wall. They serve variable purposes:
The hot knife
is the first tool. Slices through things, good for making pits. It will be useful in creating the rot-holes in the stump.
The sculpting tool
is the second one from the top. The taut wire is useful for eliminating mass and creating the general shape before fine-tuning.
The precision engraver
is the third tool. It's useful for extremely fine details. As such, it doesn't heat up as much as the other tools, and can be put on very low heat in order to make precise marks.
The freehand router
is the bottom-most tool. The wire can be bent into different shapes for different purposes. It is probably going to be the most important of the four hot wire tools for this project.
I stacked a few leftover EPS foam sheets for practice, in order to test the foam tools and color mixing Drylok:
It's a bit difficult to distinguish the contours because the foam is white, but these are practice sculpts. The freehand router was used to carve all of this. Like in the photo of the four docked tools earlier, the freehand router has three bulges, and each one is different. I can keep things from looking symmetrical by turning the tool upside down, then right-side up, and varying it in that manner continually during the sculpting process.
Mixing colors to correctly get what I want to be the base colour of the stump has been a struggle. At first, I did not know that I could use acrylic paints in Drylok, so that I just used the three different colors of concrete dye I had available. Those were charcoal, buff, and brown.
The lighter, tan / beige / cream / yellow color you see is nearest to what I want to cover the foam with first, but it isn't quite there yet.
I will be making notes to myself as time goes on. This is another uninhabited terrarium, so whatever chemical problems are created by melting EPS foam will not be a concern.
As always, I welcome any cautions or suggestions from anyone.