Category Archives: composite

Junkyard Crossbow Aims to be a Car Killer

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[James], aka [Turbo Conquering Mega Eagle], is not your typical Hackaday poster boy. Most of his builds have a  “Junkyard Wars” vibe, and he’d clearly be a good man to have around in a zombie apocalypse. Especially if the undead start driving tanks around, for which purpose his current anti-tank compound crossbow is apparently being developed.

At its present prototype phase, [James]’ weapon o’ doom looks more fearsome than it actually is. But that’s OK — we’re all about iterative development here. Using leaf springs from a Toyota Hi-Lux truck, this crossbow can store a lot of energy, which is …read more

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Casting Machine Bases in Composite Epoxy

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When you’re building a machine that needs to be accurate, you need to give it a nice solid base. A good base can lend strength to the machine to ensure its motions are accurate, as well as aid in damping vibrations that would impede performance. The problem is, it can be difficult to find a material that is both stiff and strong, and also a good damper of vibrations. Steel? Very stiff, very strong, terrible damper. Rubber? Great damper, strength leaves something to be desired. [Adam Bender] wanted to something strong that also damped vibrations, so developed a composite epoxy …read more

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Soluble Molds For Composite Parts

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People have been experimenting with 3D printed molds for fiberglass and carbon fiber for a while now, but these molds really aren’t much different from what you could produce with a normal CNC mill. 3D printing opens up a few more options for what you can build including parts that could never be made on any type of mill. The guys at E3D are experimenting with their new dissolvable filament to create incredible parts in carbon fiber.

For the last year, E3D has been playing around with their new soluble filament, Scaffold. This is the water-soluble support material we’ve all …read more

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A Car Stand made of Sand

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When the guys at [Practical Engineering] say they have a dirty car stand, they really mean it! They made a block of dirt and sheets of fiberglass as reinforcement material, and the resistance was put to test by using it as a car stand. And yes, the block does the job without collapsing.

Soil is a naturally unstable material, it relies only on friction for structural stability, but it has a very low shear strength (the resistance of the material’s internal structure to slide against itself). Therefore, as soon as you put some weight, a soil structure fails. The trick …read more

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A Car Stand made of Sand

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When the guys at [Practical Engineering] say they have a dirty car stand, they really mean it! They made a block of dirt and sheets of fiberglass as reinforcement material, and the resistance was put to test by using it as a car stand. And yes, the block does the job without collapsing.

Soil is a naturally unstable material, it relies only on friction for structural stability, but it has a very low shear strength (the resistance of the material’s internal structure to slide against itself). Therefore, as soon as you put some weight, a soil structure fails. The trick …read more

Continue reading A Car Stand made of Sand→