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| Deadly hot glue gun |
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| angelcruiz:
Hello, I wanted to share with you a scary, but not unexpected security fault I have just discovered in a cheap chinese hot glue gun. Well, it doesn't even deserve to be called a security fault. It's just a hazardous deadly shameful evil-minded "tool". I always doubt about the safety standards of such cheap tools, but seriously, this is nuts. Today, I was applying some hot glue over an aluminum surface. I was grabbing the piece with one hand, the gun in the other and, as I approached the tip of the gun to the metal, I felt that unmistakable tingling of electric current through my hand. First, I just thought the gun might be leaking some current, so I checked the voltage at the tip and... 180V RMS. Next, I measured the resistance between both plug pins and the tip and, sure enough, one of them was shorted to it. This is the weapon, in all of its inglorious shame. I still can't believe such a dangerous thing, and who knows how many like it, are being sold through Amazon without any regulation. Every time you plug one of those to the wall, you have 50% chance of having a live mains voltage exposed pointy metal nozzle. With this in mind, who cares about the 28 AWG wire, or the 1/4 watt resistor it uses to supply the led. Btw, ¿any budget, reliable and, juuust a little bit safer, hot gun? Thank you all. |
| angelcruiz:
Well, It turns out it's not a purposely made hazardous tool. As you can see in the images below, after further inspection, it has a heating element, which is supposed to be insulated from the tip with some (oh my) kaptom tape . But it has being punched somehow and it's making contact with the nozzle. Who'd ever figure :palm: |
| wraper:
Seems like some metal debris got in and then pressed into insulation by that removed clamp. However such equipment must pass hipot test at factory which would show the issue even if it was not shorted at the time. |
| Benta:
Cheapness has it's own price. I hope you've learned this now. Buying quality is one moment of frustration (price) and decades of happiness. Buying crap is one moment of happiness (price) and a time of frustration afterwards (no reason to mention decades here...) |
| NiHaoMike:
If the rest of the gun works well, I would opt for replacing the heater with a low voltage cartridge heater of the kind used in 3D printers, then add a temperature sensor and microcontroller as a PID controller. It would heat up really fast and have the option of being battery operated. |
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