Introduction: DIY Spot Welder
The new project of make it extreme is the transformation of an old microwave oven into a brand new spot welder. How did we manage that? Firstly, we decomposed the microwave oven and took its transformer and the fan that cools it. The particular project was planned not to make a portable spot welder but one with a stable basis.
Step 1: Metallic Frame - Transformer - Copper Cable
Therefore, we made a metallic frame with a stable basis to support it and we also made some holes on it in order to be able to be screwed on the spot where it will be located. After that, we removed the one copper coil of the transformer and we passed a single coil of a copper cable through the frame, 16mm thick in order to reduce the volt and increase the ampere. Regarding the edges of the cable, we made two copper spikes 25mm of thickness. Then, we placed the cables with the transformer on the metallic frame and after that, we put the spikes on two calipers. The one caliper that is located on the frame remains still while the caliper which is on the upper side opens and closes by just a simple touch on a stepper that we placed on the basis of our machine. Thus, by just stepping on this stepper the calipers close and come together enabling the electricity to permeate the spikes.
Additionally, a spring was placed on the moveable caliper that brings it back to its original position when we release the stepper. To regulate the pressure between the spikes, we placed a mechanism with a spring on our stepper that keeps the stepper moving even if the spikes come together.
Step 2: Control Panel
On the upper side of our machine we placed the control panel that regulates the thickness of the pieces of the iron plate that we need to glue together. On the control panel, we made a timer relay switch that defines the time needed for the weld and as it is commonly known when we glue thicker objects more time is required. Therefore, we have the potential to define the time needed according to the thickness of the material that we glue aiming to the desired outcome. Beside the timer, there are also two indicative lights and a switch on the control panel. When the stepper of our machine is not pressed, then the red light is pressed indicating the machine is not ready to start the weld. However, when we press the stepper and the light is not red anymore but becomes green, we know that it is ready to start the weld. Starting the weld and pressing the stepper, electricity permeates the spikes as well as the metal sheets that we need to glue within the time period that is set.
Step 3: Video
Therefore, the weld is carried out through a safe, controlled procedure. Moreover, the fan that we took from the microwave oven and we placed it behind the transformer keeps the transformer’s temperature low enabling us during the weld process to carry on gluing endlessly.