“Robotruck,” Huh?



And the not-so bulletproof windows

So, Elon Musk has rolled out his “Cybertruck”, and I am profoundly unimpressed.

Honestly, I don’t think that Tesla was impressed either, as they set the deposit at only $100.00, as opposed to the $2500.00 deposit required for the Tesla Model Y, and $1,000 for the Model 3.

Its skin is made from 3mm (.118 in) thick 301 stainless steel skin which Musks refers to an an “Exoskeleton”, which means either that it is a unit body (skin is not a part of the structure, also called semi-monocoque), or a monocoque (skin is a part of the structure).

According to Musk, this is literally bullet proof, being able to stop a 9mm round at 10 meters. (The numbers work out for this)

Most trucks, by comparison, are body on frame, where there is a structure , typically a ladder frame, upon which the body is mounted.

This is one reason for the gradual taper behind the passenger cab, it’s needed for a stiff body.

Unit body is typically lighter than body on frame, and monocoque is lighter still than unit body, but significantly more difficult to manufacture, which is why it unit body is far more common in mass produced automobiles.

Also unit body makes implementing changes in the body of the car easier, since the skin merely needs to mate to the frame.

In aircraft, where weight is more significant, a full monocoque is typically used.

In any case, the skin is about 4 times thicker than that of a P-51 Mustang, which was aluminum which is about 2½ less dense than steel, so this is HEAVY.

Based on the pictures shown, and the thickness of the skin, the weight of the just skin is in the 4000 lb range.

When you add in windows, tires, motors, a 500 mile battery, tailgate, seats, electronics, lights, etc.  I do not see the weight of the vehicle being any less than 8,000 pounds, and it might very well exceed 10,000 pounds.

By comparison, a Ford F-150 is about 5,500 pounds.

As such, not only will the car be expensive to operate, more weight means higher power consumption, but the handling is likely problematic, particularly in off road mode, where getting stuck in the mud is a thing.

The angular appearance of the truck may be driven by the choice of material and thickness, as 300 series stainless work hardens a lot, and at 3mm thick, it could be difficult to put complex curves in it.

Also, I’m not sure how it would corner at that weight.   I’m thinking that it’s in the, “Looks like a fish, moves like a fish, steers like a cow,” category.

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