Noob question - how often to replace coils?

[djironic]

How often do you replace your coils on an RDA? I've been vaping a Kanthal 30g microcoiled RDA on and off for about a week, and it seems that the flavor has dropped off, and the resistance has increased from the original 1.6 to 2.0. I've been cleaning and dry burning pretty much every night. I didn't realize coils degraded that fast - is that normal?

 

[Weizenheimer]

Not normal. If the res has gone up that much, check that your screws are tight. I have had res jump up before from screws backing out.

 

[State O' Flux]

Not normal. If the res has gone up that much, check that your screws are tight.

This... most likely issue.

Kanthal wire does "wear out"... but even with relatively thin 30 gauge, it will take several weeks to a few months. When heated, Kanthal wire (iron-chromium-aluminum) builds up an aluminum oxide thermally conductive coating on it's outside surface that protects the individual coils from shorting, one to another. This is called alumina (Al2O3).

Once the aluminum content diminishes to the point where that oxidation resistant, electrically resistive alumina layer isn't produced... all that remains is iron and chromium oxide.
Exposure & contamination degradation, inconsistent heating, increased resistance and ultimate wire failure aren't far behind. Chances are, you'll see the blackened, pitted wire or perhaps even taste the iron, long before that failure occurs.

Cheers

 

[djironic]

Tightened the screws - nothing (they seemed tight). Fiddled with the coil in some nondescript way (flicked it with my fingernail) - bingo! Back to 1.7ohm...

So who knows, lol (and I did confirm first time around that the coil was not touching the posts, lol)

*shrug*

 

[eyerhere]

Your ohms changing could also be a crossed wrap or the coil miss shaped from clening. Personaly I only get about a week before I have just gotta play and rip out a perfectly good coil just for the fun of trying somthing else. Replaced my addiction (smoking) with a hobby (vaping) that became a compulsion (building). Gotta love it!