Review on VEVOR Portable Vibration Double Tube Sensitive Printmaking by Kelsey Brown

Price (bought at $85) and physical build quality are positives. The problem comes with the temperature control. The temperature may rise 15-20 degrees above set point before falling again. As an engineer, I understand the cause of this problem. The problem is that the controller is a "bang-bang" controller (on and off). I connected the device to a wattmeter so I can confirm that the device draws either 800 watts (full power) or 0 watts (no power). The switch-on temperature is 3 degrees lower than the set temperature, and the switch-off temperature is the same as the set temperature. So it consumes 800 watts to the point, where it stops using electricity. I measured the time between switching on and off to be around 30 seconds. After power off, the temperature will keep rising even if it doesn't consume power. There are several ways to solve this problem. First, use proportional control (power consumption is proportional to how far you are from set point - don't hit the floor (800W) as you approach set point). Maybe proportional control is unrealistic for such a cheap device? Alternative solution: Do not set the switch-on point 3 degrees lower than the setting. This reduces the duty cycle to slightly less than the observed 30 seconds. Shorter switch-on times mean less inertia-related setpoint overshoot. Were the engineers afraid of the limit cycle? This is the problem that several minutes pass from switching on the heating element until the next time it is switched on. Can anyone tell me how to change the power on setting? I would like to change it myself if I knew how. I left it anyway because I could foresee such shaky behavior. I just wait a while after the temperature drops off the tip before pressing. I noticed that my device doesn't have a momentary off switch, which confused many due to the lack of instructions. My device automatically detects an external device (in this case a lid press) and powers it. Someone somewhere did a hardware upgrade. You probably didn't check the system again after the update, or they must have found a problem with the temperature control. Your humble beta tester. Who will tell How do I change the power on setting? I would like to change it myself if I knew how. I left it anyway because I could foresee such shaky behavior. I just wait a while after the temperature drops off the tip before pressing. I noticed that my device doesn't have a momentary off switch, which confused many due to the lack of instructions. My device automatically detects an external device (in this case a lid press) and powers it. Someone somewhere did a hardware upgrade. They probably didn't check the system again after the update, or they must have found an issue with the temperature control. Your humble beta tester. Can anyone tell me how to change the power on setting? I would like to change it myself if I knew how. I left it anyway because I could foresee such shaky behavior. I just wait a while after the temperature drops off the tip before pressing. I noticed that my device doesn't have a momentary off switch, which confused many due to the lack of instructions. My device automatically detects an external device (in this case a lid press) and powers it. Someone somewhere did a hardware upgrade. They probably didn't check the system again after the update, or they must have found an issue with the temperature control. Your humble beta tester. I'll just wait a while after the temperature drops from the tip before I press. I noticed that my device doesn't have a momentary off switch, which confused many due to the lack of instructions. My device automatically detects an external device (in this case a lid press) and powers it. Someone somewhere did a hardware upgrade. They probably didn't check the system again after the update, or they must have found an issue with the temperature control. Your humble beta tester. I just wait a while after the temperature drops off the tip before pressing. I noticed that my device doesn't have a momentary off switch, which confused many due to the lack of instructions. My device automatically detects an external device (in this case a lid press) and powers it. Someone somewhere did a hardware upgrade. They probably didn't check the system again after the update, or they must have found an issue with the temperature control.