Uploaded May 2025 | Updated September 2026, 1 week ago
I tried building a spot welder with a regular transformer—no MOT, no secondary rewind. Will it work?
Can you turn a regular transformer into a spot welder—without tearing it apart?
In this hands-on experiment, I try just that. Starting with a big transformer and a single-turn aluminum coil, I build a makeshift spot welder without replacing the secondary. Along the way, I upgrade the electrodes, swap in copper, and double the cable size… but something still doesn’t add up.
📉 Why won’t it weld?
🔍 I break down the circuit, trace power losses, and uncover the real culprit: voltage that’s just too low. But it takes too much to explain why here in the description, you really need to watch the video!
⚡ With a risky high-voltage hack, I finally prove the theory—and manage to weld a piece! (Even "overweld" it!)
While this project didn’t end in a fully working spot welder, it delivered valuable insights into spot welding, high-current behavior, and transformer design.
Plus, it sets the stage for a future project: a DIY capacitive discharge welder.
#DIYSpotWelder #TransformerHack #HighCurrentExperiment
Full series of #Electronics:
youtube.com/playlist?list=PLwbCeSU2Kq_zORt4un2iQ3JUYxzWF3cTJ
Subscribe the mailing list: accidentalscience.com/regform.php
Website: accidentalscience.com
I tried building a spot welder with a regular transformer—no MOT, no secondary rewind. Will it work?
Can you turn a regular transformer into a spot welder—without tearing it apart?
In this hands-on experiment, I try just that. Starting with a big transformer and a single-turn aluminum coil, I build a makeshift spot welder without replacing the secondary. Along the way, I upgrade the electrodes, swap in copper, and double the cable size… but something still doesn’t add up.
📉 Why won’t it weld?
🔍 I break down the circuit, trace power losses, and uncover the real culprit: voltage that’s just too low. But it takes too much to explain why here in the description, you really need to watch the video!
⚡ With a risky high-voltage hack, I finally prove the theory—and manage to weld a piece! (Even "overweld" it!)
While this project didn’t end in a fully working spot welder, it delivered valuable insights into spot welding, high-current behavior, and transformer design.
Plus, it sets the stage for a future project: a DIY capacitive discharge welder.
#DIYSpotWelder #TransformerHack #HighCurrentExperiment
Full series of #Electronics:
youtube.com/playlist?list=PLwbCeSU2Kq_zORt4un2iQ3JUYxzWF3cTJ
Subscribe the mailing list: accidentalscience.com/regform.php
Website: accidentalscience.com
