Why is there a hole in the lid of some Kiwi shoe polish cans?

Chief Scott replies:

(In a departure from our usual practice, this question is being answered by the person who asked it–veteran Straight Dope Message Board poster Chief Scott. But we’ll let him tell the story. –SDSTAFF Dex)

There are more important questions that need answering. I’ll give you that. But this was the first query I posted to the Straight Dope Message Board, and it was answered with nothing more than self-admitted speculation or WAGs (wild-ass guesses) by our intrepid band of posters. It fell to me to ferret out the truth.

A little more than a year ago, while cleaning and polishing my boots, I noticed again the small punched hole in the lid of my tin of Kiwi brand shoe polish. I had first noticed these holes about a year previously. I was sure they had never been in the lids before and wondered why they were there now.

Each day I pondered their purpose while shining my footwear, but promptly forgot about them once my task was completed. Not this time, though. I posted the following question to the SDMB and began the most obsessed eight days of my life:

In the 1-1/8 oz. (31g) size black Kiwi shoe polish there is a hole punched into the lid. The hole is covered by a circular, airtight plastic tab. The holes are not in every tin though, so there is probably not a universal reason for them. Often there is a little oily “slick” atop the wax in the tins with holes, but not every time.

I really had two questions: Why are there holes in the lids? And why aren’t they in every lid?

Responses hit the board rapidly. I felt obliged to “shoot down” what I deemed flawed guesses. Some of the theories advanced and found wanting (by me, anyway) included:

• The cans are sealed and probably airtight. These vents would prevent the tins from popping open while being shipped to a higher altitude. OBJECTION: The holes were covered over and no air could be vented from the tins.
• The forming machine would punch a hole in the lids as part of the tin manufacturing process to keep the metal from sliding around in the dies. OBJECTION: If this were true, why weren’t the holes in every tin?
• They punched holes in the lids to inject the wax, thereby preventing it from spilling when capping the tins. A good guess, but again, why not use it for every tin?

I was giving up hope of a correct answer when SDMB habitue AuraSeer recalled a “Car Talk” segment in which the hosts answered the question. They said that when the wax gets old it starts to dry out in some of the cans. So what the folks in Douglassville, Pennsylvania, do is take back the cans with dried wax, punch a hole in the lid, add some “oily goop to re-wet the polish,” re-seal the hole with a clear plastic tab, and ship the refurbished wax back to the retailer.

This was the best answer I’d gotten but still didn’t ring true. Why go to the expense of recalling the polish and reshipping it? How did they know which tins had dried out? Why did some tins dry out and not others?

I kept on. After several unanswered e-mails, a registered letter and a hastily placed long-distance call to Douglassville directory assistance, I found that Sara Lee Corporation had purchased Kiwi Brands. Lorraine answered their customer assistance hotline.

It turned out that we had the solution entirely backwards. The holes were placed in the lids to let an “oily goo” evaporate! Several batches of the black shoe wax were apparently mixed incorrectly and an oily substance (Lorraine’s words) was rising to the surface of the polish. Once Kiwi headquarters was made aware of the problem they were faced with throwing out all of their stock from these batches, which would cost a lot of money, or else fixing the problem as cheaply as possible. They opted for the latter. Temporary workers were set to the task of punching a small hole in the lid of each tin in the affected batches. . These tins were left sitting in storage and the holes were covered prior to shipping.

I rejoiced. I had the definitive answer to the question–an answer no one (if you’ll excuse the pun) would be able to punch any holes in. If I’ve piqued your curiosity, you may peruse the original threads dealing with this issue in the SDMB archives.

This question was a watershed event for me. It showed the value of tenacity in the quest for the truth and the importance of not accepting easy (but wrong) answers. It also showed that no matter how small or petty the question may seem, there is a correct answer somewhere and someone knows it. The challenge is to find it.

Chief Scott

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