alt Hacker NewsSame. Initially I was optimistic about the Cybertruck because I though “flat metal panels and no paint is going to make both manufacturing and repairs so much easier and cheaper”.
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They built that truck backwards and upside down. The single-piece forged aluminum frame was basically impossible to repair and brittle. Typical truck frames flex, they're part of the suspension. For small accidents, the frame can be bent back. The CT would just crack, requiring extensive aluminum welding to fix which is waay harder than welding a steel frame.
I thought this is not relevant tbh.
Either you have a modern expensive car and insurance which knows how to handle it properly, or it doesn't matter anymore and you got to a cheap car doctor.
There were no flat panels. That was a sales pitch. In reality, a slight curve to a panel adds so much strength that it can be made considerably lighter/cheaper than a flat panel of sufficient strength. Flat panels also tend to dent inwards very easily, which is not a good look for a car. Then there is the issue of thermal expansion. A pre-bent bit of metal will expand in a predictable way. A dead-flat panel could buckle in multiple unexpected ways.
I had a jeep wrangler once. The window was "flat" but not if you looked at its reflection. There was an almost imperceptible but complex curve, no doubt for strength.
Repair will be easier and cheaper? :D
As the DeLorean community will tell you, repairing unfinished stainless steel to aesthetically pleasing levels is almost impossible.
Take a piece of tinfoil, crumple it, then try to uncrumple it to its factory finish.
Repairing painted bodywork is easy and cheap: hammer it to get a rough shape, apply fillers, then paint & polish to factory finish. Simple as.
how you repair steel panel and also make it look nice ?
...you don't. You replace it in whole. You can't use filler to mask small dents and paint over it, if you want it to look as before, you have to pretty much replace it.
Paint has been well studied. We know how to do it really cheap and automated these days. Cheap is relative. I'm sure that we're talking tens of millions of dollars to get all the equipment needed. But on a scale of factory and for how long it will last, that's cheap.
Flat metal is more expensive than curved metal. Curved metal, you design the curves to help support the stress points: you can get by with thinner sheets. Flat metal requires thicker heavier more expensive sheets of sheet metal in order to be strong enough.
Curved metal also lets you design the whole thing to be more aerodynamic. which is an important consideration even with something as un-aerodynamic as a truck.