Duct Tape Comparison

DEAR TIM: I have a love affair with duct tape and have found hundreds of uses for the product. But lately some of the duct tape I buy just doesn't seem to be like the duct tape I remember using five or ten years ago. Some rolls of tape seem less substantial. Plus, duct tape never seems to hold well to things like rough lumber, brick, concrete and other slightly rough surfaces. Why is that? Is there a really great duct tape you know of? Steve L., Altadena, CA

DEAR STEVE: Duct tape has rapidly gained a positive reputation for fixing things much like the image I have in my head for bubble gum being used as a repair compound in radios during WW II. Duct tape's design that combines a reinforced backing with wide pieces of tape allows it to really perform well when you compare it to traditional masking or clear cellophane tape. These lightweight tapes simply do not have the same characteristics that strong duct tape possesses.

Rolls of duct tape my be the same size and look alike, but believe me there is an enormous difference in performance and durability. PHOTO CREDIT: Tim Carter

Once you start to look closely at different duct tapes, you quickly learn there is a big difference between products. Common duct tape consists of three layers. There is a protective shell that you see once the tape is applied. The middle layer is a reinforced backing that often has threads of fiber going in two different directions. The final layer is the actual rubber-based adhesive.

Although most duct tapes have all three components, they are by no means the same. In fact, the difference is striking if you actually look at pieces of duct tape while they are held in front of a flashlight. The light allows you to actually see the number of reinforcing threads in the backing of the tape. Some tapes have far more threads more closely spaced than others.

Some manufacturers have stated they do make different duct tapes that are of different grades and quality. This may explain why you are finding duct tapes that seem thinner and less substantial. When taken into a lab, different brands or grades of tape reveal what you have discovered. The thickness of the adhesive layer on the tapes can range from 7.5 to 12 mils. That may not seem like a big difference unless you get out a calculator. The tape that has 12 mils of adhesive has 60 percent more glue than the cheaper tape!

Traditionally duct tapes have adhered very well to smooth surfaces. This happens because there is just enough adhesive to stick to the smooth surface area. But when traditional tape encounters an object that has a rougher texture, the dynamics change. The rougher surface presents a surface area far greater than what the adhesive on the tape can handle.

But those days are over as there is a new duct tape that in fact sticks very well to both smooth surfaces, concrete, brick, stucco, rough lumber and steel. This new wonder duct tape achieves this goal by boosting the amount of available adhesive on each strip of tape. There is plenty of adhesive to fill the small gaps and surface irregularities in these rougher objects.

There is 50 percent more adhesive on this new tape than the current best duct tape on the market. The new tape has 153 percent more adhesive than the low quality tapes you can find at the home centers. It is no wonder it sticks to so many things since there is an abundance of adhesive.

Keep in mind that the tapes must resist failure if you are really stressing them. Common duct tapes that you have been using for years often have tensile strengths of anywhere from 20 to 35 pounds per square inch of tape. The new high-performance duct tape boasts a tensile strength of 58 pounds per square inch.

Although nearly impossible to prove, there may be another reason why you have seen a degradation in quality of duct tape over the years. I have every reason to suspect that pricing pressure applied by large retailers to the actual tape manufacturers is partially to blame.

Think for a moment. If you were a manufacturer and a retailer told you the only way you would get an enormous order was to lower your price, what options do you have? One option is to extract higher efficiencies in the manufacturing process so your profit doesn't suffer. Another option is to lower your cost by using cheaper ingredients or less of the current ingredients you currently use.

Add to this the fact that a certain segment of the buying public will always buy the cheapest product in any given category. They may do it because that is all they can afford or they may do it thinking they are really saving money. It doesn't matter what the reason is, certain manufacturers decide they want to sell their product to these people. I can't really fault them.

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