In the not too distant past, I needed to make 20, seven-ohm resistors I
used in a 10KW load. I wound the resistors from 14 gage nichrome wire (I
know not exactly what you are going to do, the winding part anyway ;-).

Anywho, I used a low temp silver solder I found at a local welding
supply to solder the wire ends to the crimp connectors. The crimp
connectors where even nickel plated. It worked great! Instead of
crimping, I just soldered the wire into the end. I think the working
temp for the silver solder was about 450 degrees F.

Just make sure the crimp and the wire is good and clean before you
solder it. Also, you can not use a soldering iron on something like
this, you will need a small torch. I just used a propane kit most
plumbers use. You can pick one up at any home owners/builders supply house.

Hope this helps.

David

Russell McMahon wrote:
> I want to be able to make my own custom valued current sense resistors 
> in lowish volumes - 1's to perhaps 100's.
> Requirements are
>
> - 0.02 ohm to 1 ohm range
> - Temperature stable
> - Up to 1 Watt dissipation - usually far less.
> - Non inductive within reason.
> - Reasonably compact.
> - Easy and cheap to manufacture.
>
> If nichrome wire was easily soldered then winding nichrome or other 
> resistance wire on a high value resistor is an obvious solution. 
> Nichrome and similar is cheap and readily available and has near-zero 
> temperature coefficient of resistance.
>
> However, resistance wire types that I am aware of tend to dislike or 
> hate being soldered. Other termination means are usually necessary 
> including welding, spot welding, brazing or crimping. I'll consider 
> all such ideas but thought that someone may have a bright idea on how 
> to achieve this. Crimp contacts seem the next easiest solution but 
> this is not a 'nice' solution.
>
> I do not want to employ existing commercial resistors, at least at 
> this stage as
>
> - Values are custom and may need to be adjusted during prototyping.
>
> - Suitable wattage, temperature invariant sub 1 ohm resistors tend to 
> be specialist and expensive compared to other costs in this 
> application.
>
> - Temperature invariant resistors are relatively rare.
>
> - I can control inductance etc as required.
>
>
> These are to be current sense resistors handling currents of up to 5 
> amps. Resistor value will vary with current.
>
>
> Thoughts ?
>
>
>         Russell
>
>  
>
>   
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