Hardened Ni200

[tchavei]

tchavel:
You could just check the resistance of a length of your wire. Take a meter of the 30 gauge and it should have 1.89 ohms resistance. the 28 gauge should be 1.19 ohms. You don't have to make a coil; you don't even have to cut the wire. Just connect 1 measured meter across your volt/ohmmeter. Or, you could connect each end to the posts on an atomizer and use an atomizer ohm meter. Measuring that great a length reduces measurement errors.
I got these values from steam engine using the advanced settings. You could use other sources such as this one: http://resistancewire.com/uploads/page/ADT2001_12_17_NI200_MET.pdf
to check the resistance of your wire.
If your resistance is off, then something is wrong with the wire alloy or the diameter.

I will do it this evening. I'm pretty sure it will be lower than expected. Problem is... Purity is usually indication of resistance and my resistance is lower than expected and the wire is rated at 99.6% nickel. It would have to be purer to have a lower resistance which I find hard to believe.

Regards
Tony

Sent from my keyboard through my phone or something like that.

 

[TheotherSteveS]

I still bet it is the wire. You know these guages are dodgy. I have some Kanthal which is 25.5 guage. I kid you not. What you see is consistent with a 0.29mm diameter wire which is just a tad larger that 29g (0.286 mm)...

 

[Nibiru2012]

A 10 wrap of tempered 30g ni 200 on a 2.4mm mandrel (spaced) gives me 0.14 on my dna 40 while steam engine predicts 0.17-0.18

My builds vary somewhat too using the Steam Engine Coil Calculator, but I believe a LOT of that has to do with the "coil leg" length. I wasn't factoring that in but then when I realized that I checked the length of the coil legs from the edge of the coil itself to the point where they first make contact with the coil screws. That was when I discovered that at the max my coil legs were anywhere from 2.5-3 mm in length. The default setting is 5 mm length on the coil calculator. I then changed that setting and my coils came in basically spot on.

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