Small Welder Box for Joining Wire

Discussion in 'The Projects Forum' started by antfuzz, Aug 19, 2013.

  1. antfuzz

    Thread Starter New Member

    Aug 19, 2013

    The purpose of this box is to weld 28 to 32 gauge kanthal resistance wire to the same gauge nonresistance nickel or silver wire. When the two wires come in contact a spark creates a weld.


    The schematic and the parts list can be viewed here. See this YouTube video for a demonstration on how it works

    This was originally designed by someone in Germany. I've been able to find all the parts needed at RadioShack except for the power supply. Schematic shows a 24 V 150 mA 3.6 W adapter. The company used doesn't ship to the United States. The closest one I've found is a 24 V 250 mA 6 W adapter from Digikey.

    I don't think I should trust buying parts from RadioShack so any help with acquiring the parts needed with the correct specs would be much appreciated. Trying to figure out the parts needed from the Digikey catalog is making my head ache.

    Is it possible to build this box by changing some of the capacitors or parts so the above adapter can be used?

    This same type of wire welder has also been constructed using a circuit board from a disposable digital camera along with a few other parts and powered by a 3.7 V 18650 battery. But from what I read they aren't very dependable. Here is one example.
  2. MaxHeadRoom


    Jul 18, 2013
    We made a similar one eons ago for welding the copper wire ends of newly wound motors coils, IIRC we used a low voltage/high current transformer and a carbon stick electrode, the carbon used to be obtained from the anode from batteries of the time.