It’s been almost three weeks since the iPhone 5 went on sale here in the US, and it’s practically impossible to find the handset. Apple’s website still shows shipping time estimates of 3-4 weeks, and both Verizon and AT&T show the phone won’t be available until November.

On the surface, it seems that Apple is once again a victim of its own success: it simply can’t make iPhones fast enough to meet demand. But apparently there’s more to it than that. Word is that the phone’s aluminum backing has been a major factor in the supply constraints…

Bloomberg reports:

“Apple Inc.’s iPhone 5 supply shortfall is being exacerbated by a quality-control crackdown at Foxconn Technology Group that’s designed to cut the number of devices shipped with nicks and scratches, according to a person familiar with the matter.

The scrapes, which sparked complaints with the iPhone’s debut last month, are due to Apple’s decision to use a type of aluminum that helps make the smartphone thinner and lighter. Senior Apple managers told executives at Foxconn near the end of September to tighten production standards, said the person, who asked not to be named because the matter was private.”

Last week, we reported that a number of Foxconn employees had gone on strike due to this so-called “quality control crackdown” in iPhone 5 production. As many as 4,000 workers reportedly walked off the job in protest of the company’s difficult job requests.

The tightened quality standards has also resulted in a parts shortage, with fewer metal backings passing inspection due to stray scratches. And this has added to the pressure on assembly line workers, who have to be careful not to corrupt the limited supply.

“For those working on assembly lines with enough anodized aluminum housings for production, the pressure has intensified, because the iPhone 5 is more delicate and easier to scratch during the assembly process, said five factory workers interviewed by Bloomberg News outside the Zhengzhou plant. They spoke on condition that their full names not be used.”

It’ll be interesting to see how Apple remedies this issue with the aluminum backings in the coming months, as the iPhone 5 is expected to be available in more than 100 countries by December. Perhaps they should have stuck with the easier-to-make glass backings.

What do you think?