Continuing the discussion from Let's Discuss Wire, What's Safe, What's Not!:
I hadn’t done any burn tests with my xCube until today, and I thought this might tie in well with the discussion of wire.
The argument I’m making when it comes to wire safety is that Nickel and Titanium are only safe to use with temperature controlled devices. Below I will try to demonstrate why I feel this way. But first let’s discuss this. We need to establish “normal” operating temperature. Most TC mod manufacturers are making mods that will go from 200F - 600F. I’ve heard of some that will go higher. Well 200F is useless, you can’t even get the slightest wisp of vapor from it at that temp. Conversely, 600F is for me a little too hot. In fact I’m finding the “range” for me is 400 - 520. I don’t typically go higher but sometimes maybe a bit lower. So how effective is temperature control in those ranges?
I ran tests on Nickel and Titanium on two different RDA decks. The Ti build was fine. The Ni one seemed problematic as the ohms were jumping around a bit. I ran some cotton through and added juice, did a couple of burns with it hence the discoloration of the Ni coil before dry burn test.
Titanium - 22ga. I used dry cotton. Did not pulse, I held the fire button until it timed out. Cotton pulled to the right after each dry fire. First sign of cotton getting singed was at 500F.
Little worse at 550
At 600 it burned practically through it.
I don’t know what the temperature is where cotton will scorch. However, it reasons that it will not scorch under TC mode with the xCube II using Ti under normal vaping temperatures. Of course this also means that even at 600F where my cotton was nearly burned in two that it still wouldn’t scorch because we’re vaping wet cotton aren’t we? Still, one of the advantages of TC is that if your wick runs dry then nothing burns. A visual inspection of the coil after the dry burns does not reveal any discolored wire or any of that dreaded whitish chalky substance. I feel as a vape wire with TC that Ti passes the test for me. How about using under wattage mode?
I started at the lowest watts and again held the full 10 seconds until timing out. I then went to 10 watts and repeated with 5 watt increments. I finally got some glowing at 25 watts and subsequent discoloration of the wire.
More at 35 watts -
Substantially more at 40 watts -
I don’t have a way to test the area where the overheating occcurred, nor was I even interested in touching it so I don’t know what the surface is like. The point is that below those temperatures where Ti starts to glow there appears to be no substantial impact to the wire from being heated under TC conditions.
The same tests with Nickel. These were done on a coil made from 26ga Ni200.
I got very substantial cotton scorching from at 450F when I had none at 300 or 350.
At 500 it was basically burnt. So I stopped there. I concluded that the xCube was not function on Ni nearly as well under TC as it does with Ti. This should not be viewed as a test between the value of either Ti or Ni as a TC wire though. All this result tells me is the mod thinks that Ni is cooler than Ti so it’s allowing more power to flow at the same temp setting where Ti is not scorching.
The dry burn in watt mode with Ni -
As you can see, nearly the entire coil has changed to an almost gray/tan like tone. However it did retain most of its reflective luster and feeling the coil it does not appear to have any residue at all. I also straightened out the coil and wiped with an alcohol prep pad. Nothing visible came off on the pad nor did the wire look any different after the wipe down. Neither did it feel different. It was a malleable as when installed and did not have any brittle or degraded feel to it.
I would also like to add that at no time during either of these wattage tests did I detect any odors coming from the coils. Now this is not to say there were no fumes or other noticeable thing emitted; there very well could have been but I stayed at arm’s length the whole time for safety purposes.
Of course I cannot claim that these tests mean that vaping either of these wires is harmless or safe. My conclusions are this -
For the xCube II that I own the device does not control temperature with equal effectiveness on Ni and Ti.
It appears on this device that it is more effective on Ti
Wattage mode will cause overheating of the wire at lower watts relative to each other and to Kanthal.
Ti wire develops a visible residue after reaching temperatures high enough to cause the wire to glow
Ni does not appear to change other than in color when reaching temperatures high enough to cause it to glow.
All in all I feel very comfortable vaping in TC mode with Titanium wire. Aside from the benefits of taste and temperature control, it appears under normal vaping conditions to be a very stable resistance wire. I do not feel comfortable with vaping with Nickel on my xCube. I feel I need to repeat these test on another mod and will do so and report back here.
