camelot-forum.co.uk

Worth a watch - he misses a couple of things but overall it's a good analysis.

Great video.

I think the guy fell into the trap many Americans do by thinking the American way of manufacturing something is automatically superior to other methods. He seems very welded to the principle that something is thrown away when it fails and therefore should be manufactured with glue and clips. That philosophy definitely makes for cheaper manufacture/assembly but not necessarily a "better" product.

VW seems to have made the whole assembly to be easily disassembled/repaired.

Stinsy wrote: ↑Thu Jun 10, 2021 9:11 amI think the guy fell into the trap many Americans do by thinking the American way of manufacturing something is automatically superior to other methods. He seems very welded to the principle that something is thrown away when it fails and therefore should be manufactured with glue and clips. That philosophy definitely makes for cheaper manufacture/assembly but not necessarily a "better" product.

He's a manufacturing guy through and through, and that shows (not particularly American though - the stuff he's talking about is from W Edwards Deming originally, but mostly got popularised by Toyota).
Possibly the best example is that resistor - VW have got a big, robust resistor which is directly liquid cooled and isolated from the rest of the electronics. Tesla have used loads of small surface-mount ones, cooled by a thermal pad to some sort of heat sink.
From a purely manufacturing point of view, the Tesla version is vastly easier to make and significantly cheaper. However, from a reliability point of view it's dreadful - those resistors will be kicking out a lot of heat (that's essentially their job) and Tesla have put them onto a component whose reliability varies with a log function of time and temperature. That's a recipe for trouble in the long term, even if the cooling pad goes to a liquid-cooled heatsink.

As for the number of bolts, VW are bright enough to know that they're expensive (this is NOT rocket science - rule of thumb is that every bolt adds £1 in cost, or at least you pretend they do at the design stage) so they're there for a functional reason. My best guess is that they may be concerned about the impact of vibration on inverter reliability - it's hard mounted onto the motor, and electronics don't like being shaken about. Having lots of nice and solid mounting points (something you can't really achieve with snap fits) may well be helpful for this.

I loved how he repeatedly refered to bolts as threaded un-fasteners, and toward the end complained that old whitworth and acme fixings could be so tight they couldn't undo them. Well make up your mind dude.

edps

spread-tee wrote: ↑Thu Jun 10, 2021 8:35 pmI loved how he repeatedly refered to bolts as threaded un-fasteners, and toward the end complained that old whitworth and acme fixings could be so tight they couldn't undo them. Well make up your mind dude.

Nobody uses those any more though - and Metric needs locking if you're in an environment that might be subject to vibration over time. We normally use thread-lock, sometimes locking wire if it needs to be serviced eventually.
If you've got something like https://www.fiamgroup.com/en/products/a ... w-feeding/ then the time difference compared to a snap-fit system is modest but still there. The design is simple enough that I'd question the value of using a robot - you could, but it's unlikely to be cost effective.

There's little difference between BSW/F and metric, only 5 degrees IIRC, so it struck me as amusing that his un-fasteners couldn't be un done, what thread was he referring to with an 8 degree angle? that sounds like a strange beast to me. He also mentioned riveting as a superior fix, but while it is true it is very unlikely to let go, the clamping force is pretty much an unknown isn't it?

sped

spread-tee wrote: ↑Fri Jun 11, 2021 8:33 pmHe also mentioned riveting as a superior fix, but while it is true it is very unlikely to let go, the clamping force is pretty much an unknown isn't it?

The time I noticed he remember riveting didn't rely on it for clamping force - it was used with the rotor pins, you'd put the rivets in at 90° to the direction of the clamping force to maintain it. Personally I'd go with spot welding for the same problem.

Mind you, have you seen what's under the hood of the Ford Mach-E and its cooling "System"?