Question about a rebuildable?

[Ed Brown]

I finally got around to the Hellvape Dead Rabbit RTA that's been in the box for about 2 months. Watched the youtube video about trimming the leads and wicking. Not bad at all, and success on the first try! I only put in one coil to get started.

The coils are pre-made, Hivewire 0.32 mm, 28 GA, and the plastic tube is labeled 0.4-0.5 OHM per coil. However, the Vapresso Luxe mod displays .23 ohms. Another mod displayed 0.25 ohms. Is there an issue? I imagine that the ohms are reduced somewhat when cutting the leads to fit inside the tank.

Or is it possible that some of the wraps in the coil are touching each other, shorting the coil? If so, what's the best way to separate them? Can't do anything now until the tank is empty.

Before wicking, is careful visual inspection enough? Could you run a piece of paper or something between the wraps to verify that they are not touching? Could you insert a knife to try to separate them? Is it a problem at all if they touch?

 

[Rossum]

What material (metal type) are these coils?

 

[Don29palms]

If you didn't fire the coil and check for hotspots before you wicked it that can affect it also. If you have dual coils in it .23 ohms is correct.

 

[Ed Brown]

there's only one coil installed.

The material isn't specified. It's actually "comp wire by wotofo." Hive wire is the style. The guy at the vape shop recommended these to go with the RTA.

I didn't check for hot spots.

 

[Jim_ MDP]

there's only one coil installed.

The material isn't specified. It's actually "comp wire by wotofo." Hive wire is the style. The guy at the vape shop recommended these to go with the RTA.

I didn't check for hot spots.

You should always be doing a dry burn/heating test on new wire... it also burns off any oily production residue. Nasty tasting stuff. ;D
I'm not seeing a problem with doing it now. Remove the RTA, stand it upsidedown for 30 seconds, unscrew the coil deck and put it back on the mod. Strip out the wick and do a standard cleaning/coil check & adjustment (running water at the tap to wash off carbons etc. Don't hit the button!!! ), and if all is well rewick and put it all back together (always triple check ohms after you get the tank back on in case of shorts).

And at least a couple years ago... all WoToFo tube coils were Kanthal. I've never used up mine and looked to reorder, so they may have expanded the product line, but if it's SS etc. it should say so on the tube label.

I had to look up the Dead Rabbit because back then all WoToFo product were "sinister" (left hand wrap and decks to match) but it doesn't look like the DR has a problem with either direection. So I can't guess where the issue may be. Or it could be a simple production fault. Test another coil from the batch.

 

[Don29palms]

there's only one coil installed.

The material isn't specified. It's actually "comp wire by wotofo." Hive wire is the style. The guy at the vape shop recommended these to go with the RTA.

I didn't check for hot spots.

If those are the coils the guy at the vape shop suggested then don't ever listen to that idiot ever again.

 

[Ed Brown]

I'm listening. Tell me more.

 

[Rossum]

The material isn't specified.

Seriously? Call me old-fashioned, but I'd be rather reluctant to vape mystery metal coils.

 

[Don29palms]

Seriously? Call me old-fashioned, but I'd be rather reluctant to vape mystery metal coils.

From what I can find they are kanthal A1 but I can't be sure. That's a reason I make my own coils.

 

[Don29palms]

I'm listening. Tell me more.

The reason I said that is those coils are going to need alot of power and get really hot especially in an RTA. For an RTA I personally wouldn't use anything more than a fused clapton or maybe aliens. There is no need or benefit. Even just regular claptons work very good. Those exotic coils look good but really don't perform well especially in a small chamber like an RTA. Of course this is JUST MY OPINION. I don't use RTAs anymore and haven't for a long time. I also don't care for kanthal. I like ni80 or SS316L. If you know someone that makes coils have them show you how to do it. It's really not hard. You can tell the difference between good coils and crappy coils.

 

[mimöschen]

A jump of 0.02ohms between different mods with different chipsets is well within the margin of error.
No need to worry.
But because of possible hotspots and residues dryburning new coils should be mandatory nevertheless, because both can produce some really nasty flavors and health issues.

 

[Ed Brown]

Aye. Lots of power for sure. The box mod is handling it, no problem, but after smoking analogs for 40 years, my lungs can't inhale deep enough to take advantage of the potentially huge cloud. Once this tank is empty I'll take it back apart, check for hot spots, rewick it, and consider my next move.

Don29Palms: I appreciate your unvarnished style. Sometimes people need to hear the truth in no uncertain terms. Keep up the good work! And thanks to everyone else for the replies. With the deadlines looming, my learning curve must by necessity be rather steep!

 

[uthinkofsomething]

Make sure you check what the coil reads as before and after you put the tank together, in an rta especially because they don't have a lot of room around them. If the coil touches the hood, cowl, chimney, whatever you call it (chamber) that will short it. If the resistance drops drastically after you put it together something is touching something, or you really buggered it up when you put your wicking in.
The hot spot thing is probably the issue. Watch a vid on working out hotspots and "strumming".
Personally I have found that many premade coils seem to be lower than expected, don't be surprised if it stays lower than it is supposed to.

 

[Eskie]

Well, this is the problem with premade coils. You can’t always trust what they’re labeled as. If they read 0.23-0.25 ohm on two different mods it’s pretty reasonable to believe that’s what they are and wotofo either labeled them wrong or made them wrong.

You’ve gotten lots of good advice. I’d disassemble now even if you lose a bit of juice and clean those coils well sry burning off the machine oil bound to be on them.

 

[Opinionated]

Aye. Lots of power for sure. The box mod is handling it, no problem, but after smoking analogs for 40 years, my lungs can't inhale deep enough to take advantage of the potentially huge cloud. Once this tank is empty I'll take it back apart, check for hot spots, rewick it, and consider my next move.

Don29Palms: I appreciate your unvarnished style. Sometimes people need to hear the truth in no uncertain terms. Keep up the good work! And thanks to everyone else for the replies. With the deadlines looming, my learning curve must by necessity be rather steep!

Honestly that RTA is all wrong for someone whose just coming off smoking for 40 years..

If I were you I'd go for something better suited to your lungs..

I use mtl rta's that are less restricted, you may try this:

OFRF Gear 24mm RTA

^^ it's on sale there, still have blue in stock, code BGG8FB will get you 5.00 off..

It's single coil, has a decent restricted lung draw, and is likely a bit better for you. Very easy to build with good flavor.

Try these coils:

10 Pack Clapton Coils 316L SS (26g/30g) or (28g/36g)

^^^

28g/36g, 3.0mm ID, 6 wraps.

 

[Ed Brown]

Lots of good advice indeed.

I did disassemble and dry burn. Sure enough, the coil wasn't glowing uniformly. I spread it out a little and got an even glow. The resistance went up from 0.23 to 0.3 ohms. A bit troubling that the resistance isn't as labeled. Moral of that story is to always test them and exercise caveat emptor.

I experimented with the power, burnt the coil a couple times at 50-60W, replaced the coil and started at low watts, working my way up, and concluded that these coils work best in this tank below 40 Watts. So that is 40W, 0.3 Ohms, 3.46 volts, and 11.5 A. The Mod Box doesn't care. At that point, the experience is similar to one of my Melo 3's with a 0.3 Ohm coil. Decent, but won't win any cloud competitions. Yeah, I coulda got by with a less agressive RTA. It's like driving a Corvette in a 55 mph zone. Not as fun, but it's still a Corvette!

Opinionated, Those coils you suggested look good. My goal with this tank is to use it on a protected mech that is on it's way from England. and then a full mech that's on it's way from China. I calculated that with 4.2V, I don't want to be below 0.5 ohms: 4.2V, 0.5 ohms, 8.4 A, and 35 W to be safe.

Now that brings up an interesting question that may require some further experimentation - One 0.5 ohm coil or two parallel 1.0 ohm coils? It would result in the same Amp draw, same power, but am Wondering if this would make any difference in flavor, time between rewickings, juice consumption, long term cost, etc.

Also, I got a Sony VTC5 18650 2600 mAh 20A battery - it has all the right markings that indicate that it is genuine.

Thanks all for the crash course.

 

[mimöschen]

0.5ohms is quite high for DL on a mech.
You will never get the full 4.2V. Because of the voltage drop/sag it'll be more like 3.7V at best, which equates to 7.4A and 27W.
As the battery drains, power wil diminish further.
At those low power levels a single coil works a lot better than a dual coil setup.

 

[Rossum]

0.5ohms is quite high for DL on a mech.

Yep. I run 0.75Ω singles and 1.0Ω parallel duals (for a 0.5Ω total) on my my mech squonkers and I'm very much an MTL vaper using small chambered atties and a fairly tight draw. I don't see these values being satisfactory for a DL setup.

 

[Ed Brown]

So I went to Advanced Vape Supply and got some 28/40 fused clapton coils, 3.0, 7wraps, 0.42 ohms, put two of them in the Dead Rabbit RTA, and put it on a Vapresso Luxe mod. This produces an amazing vape at 40 watts. Nice and warm but not too hot, with great flavor.

The Dead Rabbit is a winner. Top air inlet eliminates leaking. Smooth, quiet, nice looking. My only complaint is that the bottom attachment between the build deck and the top takes a little practice to screw on correctly. Once you get past that, it's a great RTA.

I got an Advken Manta RTA, with bottom air intakes, and it really likes to leak. I put in extra o-rings as shown in a youtube video and it's ok now, as long as you don't fill it more than half full.

Awaiting delivery of a Geekvape Zeus X which is highly touted.

 

[vaper1960]

Good choice on coils... I agree with what Don said... simple claptons. I'm using similar in my RDA (even though I could use fancier/lower ohm coils) 3mm, 0.8 ohms (0.4 dual) 6 wraps and 35 watts. Nice cool vape and my single battery mod lasts longer. I close the airflow down half way (restricted DL)