It’s hard to imagine, but we’ve only been using electrical tape for just over 70 years. Prior to that, in the 1930s cotton friction tape was used. It’s not exactly clear how cables and wires were repaired in a way that ensured they were insulated with cotton tape, but when electrical tape was invented by 3M in the 40s, it was a game changer due to its insulative and flexible nature. When you need to patch up a cable that’s exposed or effect some other repair, electrical tape should be used over any other type. The safety of your life and property could depend on using electrical tape and using it properly.
Electrical tape is an excellent example of a modern engineering miracle. Early attempts to create electrical tape were unsuccessful due to the fact that early tapes had issues with the chemicals migrating leaving the vinyl of the tape with an oily quality and an adhesive that just wouldn’t last. Luckily, in 1944, three engineers at 3M, including Esther Eastwold (who also had a patent for magnetic recording tape), finally discovered an adhesive that played nice with the vinyls and plastics and by 1946 the patent for 3M’s No. 33 brand electrical tape had been awarded. The original tape wasn’t the black we know today, but rather it came in yellow or white. The black color didn’t come for another 20 years in 1966 and was called the “Super 33,” and the color wasn’t for aesthetic reasons, it was to protect against degradation from UV light. Further improvements came with the 33 Plus and the Super 33 Plus which had higher operating temperatures – 221 degrees over the previous 176 degrees.
It’s worth mentioning that 3M has not only a large selection of electrical tapes like the 3M 33 Electrical Tape series, but many other tapes for industrial use as well. While we carry the full line of 3M tapes, a few worth mentioning are the Super 88 Electrical tape which features protection up to 600V, is abrasion resistant and is thicker than the standard. The Scotch Fire and Electric Arc Proof Professional Grade Tape 77 Black (and White) protects against fire hazards and electrical arcing until the defective circuit can be managed.
In addition to electrical, other industrial tapes are available including Mastic tape for various heavy duty applications from HVAC to mining work. Mastic is basically a water-based paste that’s usually applied in HVAC to seal gaps, meaning that having this on a tape makes application incredibly easy. The Mastic tapes, including models 2200, 2210, 06147 and 06149 are self-sealing for the most part ensuring tight seals. This tape is great at sealing moisture among many other capabilities.
Even once you find the right tape for the job, and you find a high quality brand like 3M, it’s only going to work right if used properly. That said there are number of techniques you can use to ensure the electrical tape will protect and insulate as intended. This video by 3M demonstrates an in-line splice using Rubber Mastic tape 2228 and a similar technique is outlined in this helpful guide and this guide emphasizes the importance of good technique. This video demonstrates a basic repair to a standard broken wire. One of the key points is to stretch the tape as you apply it to ensure full adhesion.
Tape for industrial and especially for electrical work has come a long way in 70 years. Starting from barely serviceable cotton friction tape to the plethora of tapes for each job available now the ability to do a quality job with quality materials has never been easier. If you need some 3M tape for a job, get in touch with us and we’ll help you get the one best suited for the job at hand.