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Caltrop 3d printed

Not a Photo

Coated Full Color Sandstone
Caltrop 3d printed
Caltrop 3d printed

Not a Photo


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  • 3D printed in Coated Full Color Sandstone: Fully colored material with a glossy and smooth finish.
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  • This product is intended for mature audiences.
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Product Description

From Heinlein's The Number of the Beast:

Zeb said, ‘This is a weapon, invented centuries ago. The points should be sharp but these have been filed down.’ He flipped it, let it fall to the table. ‘No matter how it falls, one prong is vertical. Scatter them in front of cavalry; the horses go down – discouraging. They came into use again in Wars One and Two against anything with pneumatic tires – bicycles, motorcycles, lorries, and so forth. Big enough, they disable tanks and tracked vehicles. A small sort can be whittled from thorn bushes for guerrilla warfare – usually poisoned and quite nasty.

‘But here this lethal toy is a geometrical projection, a drawing of the co-ordinates of a four-dimensional space-time continuum. Each spike is exactly ninety degrees from every other spike.’

‘But they aren’t,’ I objected. ‘Each angle is more than a right angle.’

‘I said it was a projection. Sharpie, it’s an isometric projection of four-dimensional co-ordinates in three-dimensional space. That distorts the angles – and the human eye is even more limited. Cover one eye and hold still and you see only two dimensions. The illusion of depth is a construct of the brain.’


He dropped me abruptly and said, ‘Attention, class. The two prongs of the caltrop painted blue represent our three-dimensional space of experience. The third prong painted yellow is the t-time we are used to. The red fourth prong simulates both Tau-time and Teh-time, the unexplored time dimensions necessary to Jake’s theory. [...]’

What's in the Box
Coated Full Color Sandstone
4.3 cm
3.6 cm
3.8 cm

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