Twisted kanthal

[drunkenbum]

I fancy having a go at some twisted coils. When it comes to calculating the number of wraps etc. do I just double the thickness in the coil calc to allow for the 2 pieces or is it more complicated than that?

[Get Off My Cloud]

Jun 19, 2015 21:23:26 GMT drunkenbum said:

I fancy having a go at some twisted coils. When it comes to calculating the number of wraps etc. do I just double the thickness in the coil calc to allow for the 2 pieces or is it more complicated than that?

You can select twisted wire in steamengine.
www.steam-engine.org/coil.asp?p=roundmulti&r=0.6&str=2&awg=28&id=2

[davetherayon]

Halve the resistance, so two kanthal leads of x winds that would EACH make y ohms, wound together makes y/2.

[drunkenbum]

That makes sense. Get Off My Cloud is there a nice easy way of guessing the ridge bit without having to get the tape measure out?

[*-SARIN-*]

I've always found the calculators inaccurate when using twisted wire especially if you are twisting it yourself so instead i make a decent length and stick the coils in, then work out whether i need to increase / decrease the number of wraps or the size. If you have pre-made stuff then it'll be the same all through the roll obviously.

[tim]

Jun 19, 2015 21:31:04 GMT drunkenbum said:

That makes sense. Get Off My Cloud is there a nice easy way of guessing the ridge bit without having to get the tape measure out?

No. Don't guess. Measure. Vape safe.

[drunkenbum]

Jun 19, 2015 21:40:19 GMT tim said:

Jun 19, 2015 21:31:04 GMT drunkenbum said:

That makes sense. Get Off My Cloud is there a nice easy way of guessing the ridge bit without having to get the tape measure out?

No. Don't guess. Measure. Vape safe.

You're right tim. I think I might make a couple, put them in and see what the resistance is. I'm sure I'll find my desired resistance after a couple of tries

[tim]

drunkenbum If you have a reliable ohm's checker, you can have a guess at the pitch of the twist, but don't trust a mod to tell you the truth. I have a twisted coil in a Subtank, and it reads anywhere from 0.8- 1.1 ohms on various mads. It is actually 0.91 ohms. That is a reading taken from 2 different ohms testers.

I typed *mads* by mistake. I meant mods, but *mads* is more correct for checking ohms

[thatguy]

The resistance of twisted wire is a bit more complex than dividing the single wire resistance by the munber of strands. As the wire is twisted, the length of each stand is greater than it would be in single strand wire, this is where the pitch comes in. The smaller the pitch, the greater the increase in length (more twists, thus a longer length of wire used)

The best advice I've seen for measuring the pitch was on steamengine. Measure the length of 10 and calculate the average.

[tim]

Yeah, what thatguy said. Like I said, don't guess unless you have a reliable ohm's checker.