In other news, I'm vaping on a new SS317L contact coil, and it's great.
This time I pre-pulsed it until it turned quickly yellow then blue; yes - I was surprised! At first I thought I had put Titanium in by mistake! But I tested multiple times and repeated it each time (as long as I didn't heat the coil for too long - it starts glowing red hot faster than Titanium does.)
Maybe that's not unexpected for those in the know (
@druckle ?), but I had no idea SS would turn yellow then blue just like Titanium.
Pulsing was done the same way I do Titanium:
- Wire: 150mm of SS317L 0.45mm / 25G, resistance around 0.76Ω
- Attached to an RDA on a random mod set to VW @ 30W (power, not TC.)
- I timed the pulse as 5 seconds to turn it partly blue - I tested this on three stretches of wire.
- On the piece below I then did a second 5 second pulse (once it had cooled down) to even the blue out across the wire.
It was super easy to coil a nice stable contact coil (helps that it's 25G):
I thought that might be sufficient oxidising for contact, but it wasn't. When trying the coil I had the same as I've seen on my previous SS contact coils: I need a couple of pulses as a contact coil before the resistance starts rising as normal for TC:
- First pulse it seems to get no resistance rise at all, the temp reading on the mod stays at 77°F like it does with Kanthal. This is effectively like a second dry pulse, because it's not limiting temp at all.
- Stopped this uncontrolled pulse after a few secs, then:
- Second pulse is the opposite, resistance rises dramatically such that it quickly says it's at 700°F or something silly.
- So it cuts power completely of course.
- Third pulse onwards, works fine as expected.
I am assuming that these are the symptoms of a coil that starts out shorting but then oxidises to fix those shorts.
During those dry burns I also saw inconsisent glowing across the coil, similar to what we see with Kanthal (part hot, part not.)
I did not have to tweak/move the coil at all to get it working normally after that - just two pulses then worked from the third.
I'm now vaping it in my Aqua SE RTA, NP set to 11 (tried
@balazsk 's setting) and temperature at 350°F. So I'm still using an offset - I tried 380 to start with and it got a little dry towards the end of a long hit. 350 with 11NP is working great.
I just drained the tank empty and the Rayon completely white, and it TP'd as expceted. No dry hits, but a nice cloudy/flavourful vape before that point.
