If you do any service work on electrical or electronic devices you have undoubtedly run into strain reliefs on power or control cords that had to be removed and replaced.
I have found these devices very frustrating. They are made of a very tough, slippery plastic. To remove them they must be compressed and then pulled from the hole where the cord goes through the chassis. Most of the time the pliers slips from the grip. If I am lucky I do not pinch myself but almost always the removal involves scratching and marring to the strain relief. The replacement is equally difficult as it usually involves compressing a new wire or cord and pushing the relief into the hole while it is compressed. This is another chance for a slip and marring. Today, after fighting with these things for the last 60 years, I finally decided to do something about it.
I began by going to the local Harbor Freight store where they sell economical tools and I bought two small vise grip pliers for $3 each. Since my plans for these vise grips were to modify them to suit my needs I did not want a lot of money invested if the modification failed. Furthermore since the job they would be doing would be relatively light duty their quality would not be an issue.
I wanted two pliers as I wanted one set where the jaws would be squarely set with respect to the strain relief and I wanted a second pliers where the jaws would be set at an angle for cases where the wire or other obstacles would not let me come directly down at the strain relief.
Here you can see the offset angled nose. The width of the nose has also been trimmed down so that it is narrower than the insert in the smaller strain reliefs that I encounter.
Similarly the straight nose has been ground down so that it is narrower than the insert in the strain relief.
The next step was to use the Dremel tool to grind the inside of the jaws. I wanted the part of the jaw that would clamp the strain relief to be narrow and rough so that it would grab a hold and not slip off the strain relief. The gripping surface needed to be narrow but not too much as I don't want it to cut into the strain relief. Directly behind the gripping points I wanted the jaws to be wide so that they would not interfere with the gripping surfaces or mar the wire.
I tested the extractors by gripping onto a test strain relief:
Even with this recessed strain relief I was able to get a good grip and compression of the relief.
Here is a brief video of the strain relief extractor in use.
Why did I fight with this problem for so many years? The solution was only $6 and 30 minutes away at any time but I chose to continue to fight with these dang things for 60 years. Perhaps it is our basic nature to tolerate some of the nuisance challenges when we are focused on the bigger picture (repairing the piece of equipment). Once the job is done the nuisance strain relief is forgotten until the next time and history repeats itself. In my case I was finally inspired by aging hands, with beginning arthritis, and a job where about 30 really tough strain reliefs had to be removed and replaced. Even with this inspiration I finished the job before I took the time to modify the vise grips. Now I am looking forward to the next time when I can slay the little trouble makers with the new extractors.
John
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