First Temp Control Build

[Caterpiller]

Built my first TC coil today.

VF DNA40 - Derringer rda

28g, 10wraps, 3mm ID, Nickel, 0.14 ohms

Read 0.16 Ohms on the VF DNA40

Started off at 400F at 20w

Vaped fine but a little thin, so pushed it up to 420F at 30w.

Here it vaped well. The temperature protection kicks in pretty quick, and after a couple of 2 second vapes it was flashing on the screen every time I took a hit.

It's hard to see the screen while vaping, but I wanted to see what the watts were while drawing air over the coil.

This is what I think I saw:

Hit the button and watts climb to 30w in less than a quarter of a second.

Then quickly drop down to around 18w. Then climb steadily to around 23w, before the Temperature Protection starts flashing on the screen.

All this within a 2-3 second vape.

Overall it worked fine. The vapour was good but nothing like the dual kanthal setup I used prior to this.

In comparison the the dual kanthal was a monster, and the TC was a ..... cat.

It's not a fair comparison of course, but I've never tried a single coil in the Derringer before.

I'd be very interested to hear if anyone has successfully run DNA40 Dual coils.

I know dual coil TC is at least very difficult to get right, not even sure if people are doing it.

I did vape the RDA dry with a pleasant but diminishing vape until the coil was almost dried out, watching the maximum watts drop into lower single figures.

So I have to say the technology seems to work well.

Overall an interesting first test, but unless I can get dual TC coils working in the Derringer, I think I'll be going back to kanthal.

My other go to atty is the Kayfun v4. I don't get dry hits from this, so won't be trying TC.

So not quite sure when I'd use TC again.

 

[Treeburner1983]

For dual TC coils I've found 32g ni200 twisted with either 34g kanthal or 0.4mm kanthal ribbon to be the ticket to getting the resistance high enough without having super-fragile coils.

Good luck!

-Treeburner

 

[Pocha]

Don't be afraid to turn up the temp. I rarely use drippers but it seems most folks are having good luck with higher temps. I usually run my tanks at 460. I recently ran a wick in a Subtank mini RBA for over a month at 460-ish and when I replaced it and rinsed it it came out perfectly white...not even singed.

A lot of good info in the Temp Control sub forum too...

 

[Cullin Kin]

Nicely done! I'm right here with you on the TC builds... Still getting used to them. Here's my first shot at a TC build:

10 wraps, 28g, on a 3.5mm mandrel.

You might want to check out a 2 post RDA, at least that's what I was recommended for TC builds. Luckily I had a Magma, but I could use an RDA with a wider 2 post setup.

As for duals, I've definitely seen dual TC builds floating around the forum... But can't really help! Sorry.

Also, sorry, not trying to detract from your thread at all.

ETA: Don't mind the iStick. It has been retired to just be my building post lol.

Don't be afraid to turn up the temp. I rarely use drippers but it seems most folks are having good luck with higher temps. I usually run my tanks at 460. I recently ran a wick in a Subtank mini RBA for over a month at 460-ish and when I replaced it and rinsed it it came out perfectly white...not even singed.

A lot of good info in the Temp Control sub forum too...

I'm glad you said this! I was sticking to 410-420ºF but the vapor is very thin and cool - not what I'm used to at all. Just went up to 450ºF and it's getting much better. Thanks for posting this!

 

[Caterpiller]

That's interesting, I'd heard the singe point (technical term ) for cotton was 420F so was trying not to go to high above this.

Looks like a tidy build Culin, well done. I'm only seeing 9 wraps there though so may come out a little lower than expected.

Looking at the photo's of mine I see I actually have 11wraps, so that explains the slightly higher ohms reading I'm getting. All good though

 

[Caterpiller]

For dual TC coils I've found 32g ni200 twisted with either 34g kanthal or 0.4mm kanthal ribbon to be the ticket to getting the resistance high enough without having super-fragile coils.

Good luck!

-Treeburner

Thanks @Treeburner1983

I didn't know you could mix coil material like that and still get TC.

Have to say I'm confused by the science.

If you twist kanthal around nickel won't the current just choose the path of least resistance and go down the nickel wire?

So I'd still need 20+ wraps to make a 0.3 ohm coil, but now it will be even bigger/longer due to the kanthal?

If I understand you, the kanthal is just there to act as a support (like scaffolding)?

Or am I missing the point?

 

[Caterpiller]

Oops, just noticed you're using 32g nickel.

Therefore only 10/11 wraps to reach 0.3ohms, so dual coil would hit my target 0.15ohms!

This is great!

Two quick questions for @Treeburner1983
Or anyone else who knows:

1.) Is the kanthal only scaffolding and not carrying current?

2.) How do you twist the wires together?

Photo's would be greatly received

 

[jks89]

That's interesting, I'd heard the singe point (technical term ) for cotton was 420F so was trying not to go to high above this.

If I remember my research right, that's the singe point for *dry* cotton. As long as your wicking is good, you should be fine going over. I've gone up to 550 before without burning.

 

[Treeburner1983]

Oops, just noticed you're using 32g nickel.

Therefore only 10/11 wraps to reach 0.3ohms, so dual coil would hit my target 0.15ohms!

This is great!

Two quick questions for @Treeburner1983
Or anyone else who knows:

1.) Is the kanthal only scaffolding and not carrying current?

2.) How do you twist the wires together?

Photo's would be greatly received

The nickel carries the current and the kanthal acts as support for the nickel. The kanthal may have a minor effect on the resistance, but overall it's just to prevent the fragile nickel from getting damaged.

To twist the wires together, cut two equal lengths and tie one end together with a knot, then tie the other end to the handle of a coffee mug. Hold the free end with pliers and spin the cup until the wire breaks off - that means it's twisted enough.

Good luck!

-Treeburner

 

[Caterpiller]

If I remember my research right, that's the singe point for *dry* cotton. As long as your wicking is good, you should be fine going over. I've gone up to 550 before without burning.

Thanks @jks89
At this point I'm only playing with TC in an RDA to see if I can vape the cotton dry every time before redripping.

Really just doing this for fun, but if I could build a dual coil TC that would never dry hit in a RDA, I would be tempted to use this instead of kanthal.

The advantage being I could be really lazy about redripping and/or checking the wick, and with dry cotton I could change flavour without mixing flavour.

Setting the TC to 550F would disable this function for me.

 

[jks89]

Thanks @jks89
At this point I'm only playing with TC in an RDA to see if I can vape the cotton dry every time before redripping.

Really just doing this for fun, but if I could build a dual coil TC that would never dry hit in a RDA, I would be tempted to use this instead of kanthal.

The advantage being I could be really lazy about redripping and/or checking the wick, and with dry cotton I could change flavour without mixing flavour.

Setting the TC to 550F would disable this function for me.

Totally get that! Just wanted to throw out my experience re: the confusing singe point.

I haven't tried twisting with Kanthal, but I have moved over to Titanium wire instead of Nickel. Titanium has a higher resistance and is much sturdier, and my two issues were fitting enough coil into the build deck and wicking without completely jacking up my coil, which Titanium has solved both of.

 

[Caterpiller]

@Treeburner1983

I really appreciate the advice - thank you!

I'll order some 32g Nickel and give it a try.

 

[Caterpiller]

@jks89

Titanium does sound a little more practical to work with. I wonder why the TC mod manufacturers seemed to choose nickel as there preference?

Perhaps you can be more accurate with nickel. I don't know.

I'm using a DNA40 which doesn't support Ti. It's a real shame it doesn't support firmware updates. I hear the soon to be released DNA200 has this and more.

I know people use Ti on DNA40's, but then your just guessing what temerature you may have set it to. I really don't like the idea of that.

Out of interest, if it's not dry hit protection you're using the TC for, then what?

To stop you're juice from getting to dangerous temperatures and breaking down? Forming nasties?

Is there a reason you set it to 550F beyond that being a good vape?

 

[jks89]

@jks89

Titanium does sound a little more practical to work with. I wonder why the TC mod manufacturers seemed to choose nickel as there preference?

Perhaps you can be more accurate with nickel. I don't know.

I'm using a DNA40 which doesn't support Ti. It's a real shame it doesn't support firmware updates. I hear the soon to be released DNA200 has this and more.

I know people use Ti on DNA40's, but then your just guessing what temerature you may have set it to. I really don't like the idea of that.

Out of interest, if it's not dry hit protection you're using the TC for, then what?

To stop you're juice from getting to dangerous temperatures and breaking down? Forming nasties?

Is there a reason you set it to 550F beyond that being a good vape?

550 was my highest, I don't normally set it there. Mainly I was just pushing my build to see what would happen. As far as temperature accuracy, Ti is usually about 80-100 degrees below nickel, so you can just set the temp lower. There's still a bit of guess work, but you're not completely in the dark.

I use TC mainly for dry hit protection with a full tank. I'm still a bit of a noob with building/wicking in general. Additionally, I do like the limiting below dangerous temperatures portion of it all.

The Evic-VT (I think that's the name of the new Joyetech mod) does support Ti.

 

[Caterpiller]

550 was my highest, I don't normally set it there. Mainly I was just pushing my build to see what would happen. As far as temperature accuracy, Ti is usually about 80-100 degrees below nickel, so you can just set the temp lower. There's still a bit of guess work, but you're not completely in the dark.

I use TC mainly for dry hit protection with a full tank. I'm still a bit of a noob with building/wicking in general. Additionally, I do like the limiting below dangerous temperatures portion of it all.

The Evic-VT (I think that's the name of the new Joyetech mod) does support Ti.

IIRC the SX Mini M Class came out with just nickel TC, but had downloadable firmware and which now includes Ti.

Seems Evolv were a bit late to catch on.

I'll try Ti when I have a mod with the algorithms to support it.

 

[Treeburner1983]

I find with nickel twisted with kanthal I have to set the temperature lower than I would with pure nickel, likely due to the heat retention of the kanthal. I have my Goblin and Goliath both set up with my ideal build, both running at 325°F and registering 0.080ohm on my ipv4's: dual coils, each 5 wraps of 32g ni200 twisted with 0.4mm kanthal ribbon, 2mm id wicked with Japanese cotton. Vape is mildly warm and very good flavor, the twisted nickel with ribbon seems to have better surface than regular nickel and with my DIY Espresso juice I can refill 10-15 times before I re-wick.

-Treeburner

 

[Tyberias]

@jks89
I know people use Ti on DNA40's, but then your just guessing what temerature you may have set it to. I really don't like the idea of that.

You can actually be pretty accurate with Ti on a DNA40. Start low and raise the temperature until you start to scorch dry cotton. That is about 450 degrees. Back it off 10 degrees and you will protect your cotton from scorching.

In truth, to really get the most out of temp control you should do this to calibrate your temperature with each new build since different wire and atomizers will introduce inconsistencies.

 

[Completely Average]

You can actually be pretty accurate with Ti on a DNA40. Start low and raise the temperature until you start to scorch dry cotton. That is about 450 degrees. Back it off 10 degrees and you will protect your cotton from scorching.

That will almost certainly lead to an underpowered vape every time.

You shouldn't worry about the scorch temp of DRY cotton. You're never going to be vaping bone dry cotton. Ideally you want the temperature to be the same as a kathal coil when it's well wicked, well juiced, and working right. The scorch temp of saturated cotton is closer to 550 degrees, and the optimal operating temp of a well wicked and well juiced coil is somewhere between 475 and 525 degrees. Set your temp control in that range and then if your wick even begins to dry out the temperature control will kick in letting you know it's starting to dry out rather than it kicking in long before your coil is hot enough to be working right.