Wednesday, June 19, 2013

When the lowest price wins

What will you pay for quality?

In the modern hyper-capitalist sense, there is an idea called 'the race to the bottom.' It means, what is the worst quality product that the buying public will tolerate that allows the manufacturer to spend the least amount of money making, while keeping the price artificially high enough so that a worse product made now is the same 'price' as a superior product made previously?

This is the terror of globalization, and no, this is not a political screed. The Chinese manufacturing sector is perfectly capable of producing very high quality products: you wouldn't call the iPhone "cheap and flimsy." Products manufactured in the US of A by ISO 9000 certified companies can be pot metal junk, as long as the process for how to make this low quality junk is well documented.

There are some parts, however, which cannot be substituted with 'less expensive materials.' That's because the less expensive materials fail to meet the specifications required to do the job. They might be the right shape, but that doesn't make their hardness, lubricity, or a dozen other attributes right for the job.

I first experienced this when I was selling audio components for Silo in 1991. That year, Sony had introduced the five disc 'Carousel' CD player which unloaded the whole tray and let you rotate a turntable carrying the disks so you could reload it for an enormous five hours of play time. These things were flying off the shelves, and then Sony got greedy: they replaced some of the moving components with plastic rather than nylon. The units looked the same, and played the same, and within about 50 open-close cycles, stripped that plastic gear that drove the rack which was molded into the tray. The tray won't come out, and now your brand new $200 player has et up $100 worth of CDs that are trapped inside it. All for the sake of $0.005 part that should have stayed a $0.01 part.

So what happens when an entire industry goes this route? Lowers the quality until what was once considered to be robust is a joke? Ask Craftsman. Anyone who works with tools will tell you that the steel, mechanisms, and specifications of a modern Craftsman tool are an embarrassment compared with the same tool made thirty years ago. While Sears will take back your broken tool and replace it with another for free (thus honoring the Craftsman lifetime warranty) it will be of the same or worse quality than the tool that failed.

This is the race to the bottom that has been happening in the VW aftermarket during the last twenty years. The only difference is that it is accelerating so fast now that parts quality is beyond redemption. VW hobbyists have always been a cheap lot: Don't buy a new one, rebuild the one you have. Limp by, rather than fix it 'right' and variations on that theme. Now, the only thing about an old Volkswagen that is still cheap...is the owner. The prices are still rising, and the parts quality is in the suds, that is, when you can find the parts at all. NLA (No Longer Available) has become the new price.

Unfortunately, this race to the bottom has only been exacerbated by the Hobbyist community itself. If you expect consumable parts (engine, suspension, brake, gaskets, seals) to stay at the same price *FOREVER*, you will inevitably wind up with parts that soak up the inflation and scarcity differential by lowering the quality of the components.

Serious VW hobbyists have taken to hoarding New Old Stock component that are still in the factory box, rather than buying a new component at one fifth the price that is of unknown durability. This fact hit me square between the eyes with a 2x4 this week: The main bearings (part #36 in the diagram) which support the crankshaft (part #1).

These bearings are the ones that take the horizontal pounding of the engine, and as such, wear out. The bearing doesn't actually touch the crankshaft: the crankshaft floats on a 4/1000 of an inch layer of oil as it spins at stock speeds of up to 4800 RPM. That oil is refreshed by pumping cooled oil into that shadow thin gap under pressure.

This is why machinists who know what they're doing can make a decent living: most people have a concept of 'small' as about the diameter of a grain of sand, or 197/1000 inches, about 50x the size of this oil gap.
The crankshaft main bearings, in which the crankshaft journals
rest on a thin skiff of oil and spin at up to 5000 RPM.

As you can imagine, the accuracy of the bearing surface and the accuracy of the crankshaft surface that floats and spins in it (call a journal) is paramount. The aircooled engine design is so forgiving that the most exceptional idiot can assemble an engine out of a box of parts, measuring nothing, and produce an engine that will run. The engine might not run for long, and might grenade itself within a month or the first time they really put the hammer down on the accelerator, but it will run.

When building for longevity however, the builder had better be compulsive about measurements and cleanliness in the assembly area. Even with good measurements, an engine assembled in a dirty shack is likely to have a service life perhaps 50% or less of one assembled in a clean-room environment.

So what was the bad news? How does material quality affect me and this engine build in particular?

Next time.

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