spot welder for nichrome wire
spot welder for nichrome wire
(OP)
I need to make a 120 volt, 300 watt heater using 32 gauge nichrome wire (10.5 ohms per ft)and have a need to make reliable electrical connection from the nichrome wire to the 16 gauge copper lead wires. I tried silver soldering (oxy acetylene with stainless flux) but the silver solder wire I had was too big and I melted the fine nichrome wire. I have read a capacitive discharge spot welder may just be the ticket. Anyone know approx how many micro farads in electrolytic capacitors I need and what voltage I should be charging it to for a good weld?





RE: spot welder for nichrome wire
Melting the nichrome while silver soldering, however, is simply a problem with your technique. Using a smaller torch tip and directing the heat mainly on the copper wire should work.
RE: spot welder for nichrome wire
I used 10,000 microfarads charged to about 70 volts.
The trick is to discharge quickly, just touching it on won't work.
Make good contact then discharge the capacitor through an SCR.
I think for a one off Compositepro has the answer you are looking for or you could crimp it.
Regards
Roy
RE: spot welder for nichrome wire
Keith Cress
kcress - http://www.flaminsystems.com
RE: spot welder for nichrome wire
I'd agree on the (suitable) terminal block approach above to tie the copper to the nichrome and, to provide a thermal barrier (enough bulk in the terminal block to provide heat sinking) at the connection.