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DIY Resistance wire

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Labrat101:
Though sheer boredom I was was looking for a Shunt resistor .
So going though years of stock piled parts etc . I needed a 0.05  \$\Omega\$ @ 50 amp .
So not finding anything that was suitable . I went into.. How hard can it be to make it  :palm:
 Copper wire ... No
 Steel wire .. Hum has a high resistance but very unstable with temperature   another No.
Putting my soldering Iron on the cleaning wire .. Brain wave . low frequency .
Those stainless steel pads we use to clean our soldering iron tips . are 410 Stainless steel  11.5% nickel chrome    :-+
 Yes . looking Good . measured it 18mm is showing 1.1030  \$\Omega\$ .
 Also taking a piece about 15cm long powering it from my lab power with 5v @ 1amp it become a very handy foam cutter .
 These steel cleaning pads Have many uses . Maybe not the best .
So just rapping this wire round a couple of copper posts , A few times I was able to get my  0.05 \$\Omega\$  for testing an quick repair of my
electronic load .  :-+ 

 These wire cleaning pads have a melting point of about 1500 C  Resistance aprox 0.5  \$\Omega\$ per cm 
  I guess they aint Quality controlled so there will be different specs .

  I'm sure there are many other DIY thing that can be made from reusing this stuff
 
  Have Fun and don't burn your fingers  .

  More Ideas welcome

jonpaul:
Use only Nichrome wire, for heaters and high temp. Crimp do not solder.

Shunts need a low TC, various resistance wire are available.

Steel wool will burn.

Jon

Kleinstein:
The stainless steel pad is a bid thin for a high current shunt. Otherwise the usual stainless steel is reasonable low TC for a material not specially made for that.
The problem is only the soldering, which is hard and needs special flux.

Zero999:
Does it copper plate easily? If so, perhaps that'll make soldering easier.

50A through 50mΩ is 125W. How did you stop it vaporizing?

Labrat101:

--- Quote from: jonpaul on January 14, 2022, 11:58:10 am ---Use only Nichrome wire, for heaters and high temp. Crimp do not solder.

Shunts need a low TC, various resistance wire are available.

Steel wool will burn.

Jon

--- End quote ---
I know steel wool burn .
This is Not the steel wool stuff .  its 1mm x 0.05 mm spring wire it seem to handle about 6 amps without a problem .
 the one I have is very tight spring wound . and cheep . as far a I can tell from running a few tests it has a high content of chrome .
 It was more of a Fun thing .

I did also find some 3kw Nichrome wire afterwards and Yes its better .
 

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