Nola (http://inchtextiles.blogspot.com.au/) suggested Kinetic Sand for mould / support making. The website describes Kinetic Sand as “98% sand and 2% Magic”, the Magic being a synthetic polymer which the Product Statement reveals to be polydimethylsiloxane, a silicone with unusual flow properties.
sand sidetrack
Sidetrack sample p1-1. I started with a simple shape – a kitchen bowl.
Sidetrack p1-1 Mould
Traced over with the 3D pen…
Sidetrack p1-1 with plastic
Lifted it off the mould…
Sidetrack p1-1 unmoulded
And embellished.
Sidetrack p1-1 Result
Structural integrity is very poor, but a reasonable proof of concept.
I also like the colour – it looks like pulled sugar. A little more sturdy and it could make an amusing bowl for lollies.
Sidetrack sample p1-2. What about a more solid shape?
I rolled smooth some kinetic sand, and pressed in a spring clip that was lying nearby.
Sidetrack p1-2 Impression
Tricky at the start, but a result of some sort, with the impression filled with wriggles of plastic.
Sidetrack p1-2 Filled
It came out cleanly – a few extra indents in the sand, suggested I pressed too much at the beginning.
Sidetrack p1-2 Impression after filling
Sidetrack p1-2 Comparison
Not an exciting example, but another world of opportunities has opened.
One oddity possibly of interest for specific needs – a short length of colour mixing in the nozzle when changing filaments.
Sidetrack p1 Colour mixing
You don’t get much length and it would be a bit of a fiddle changing the filament, but perhaps an ombre effect could be useful sometime. Or I might want a small amount of a particular colour I don’t have.
Other ways of colour mixing?
Sidetrack sample p1-3. An imprint of today’s earring (itself claimed to be made from old silver cutlery).
Sidetrack p1-3 Impression
Bits of colour pressed in – snippets of plastic from earlier experiments. (Sorry the photo is rotated. I thought it would fit the screen better)
Sidetrack p1-3 With inclusions
The T-pin is to keep a hole for connection to a potential ear-wire.
Sidetrack p1-3 Result
The earring came out cleanly, the colour fragments well attached, but the hole flawed.
Sidetrack p1-3 Flaw before and after
The fix turned out to be easy.
Sidetrack p1-3 Sideview
It’s very light, but feels solid. I think this is a greet way to make beads and dangles.
Or I could make shapes relevant to a particular theme in a work. Perhaps work at making it smoother. Or else a series of more or less wriggles, or more or less complete shape, or different colours…
Sidetrack sample p1-4. Can I create a 3d shape, go over it entirely with filament, and extract the sand?
Sidetrack p1-4 With Plastic, and small insert showing initial mould
Drawing on the shape was awkward at first, but one could build skills.
Next was getting the sand out.
Sidetrack p1-4 Removing sand
It took a few minutes, but I now have a somewhat fragile filigree ball. I could add more decoration, say some extra snippets of colour, but didn’t feel I’d learn anything extra from that.
While this was successful in the sense of doing what I set out to, I don’t think it’s the best way of achieving the objective. It also wouldn’t work for more complex shapes.
I think depending on the project you need a mix of working on the flat; freehand 3D; over a mould; into a mould; creating as a whole; joining pieces… I really like this pen, and the Kinetic Sand is a great addition to the toolbox.
Fibres of Being 
Oh wow, it worked! I am so pleased. I especially liked the filigree ball shape. I guess you could make a mould of anything, even scrape it back like sculpting, and then make your base structure over for later embellishment. Maybe not where you want go right now, though!
It’s wonderful stuff – thank you again for the great tip! I’ve been using it some more today, just keep finding more things to do.