My Coil Rebuilds Keep Reading Low Ohms

[WestonG91]

Hey,

I've been rebuilding Protank heads for a while, but I've never had any way to check Ohms until recently. I used 5 wraps of 32 gauge Kanthal around 2.5mm Silica with a needle or around a cocktail stick for a cotton build. I've been vaping this build for a couple months on basic Ego batteries with no problems. I just bought an eGo-V v3 that can read Ohms, so I was curious to see exactly what Ohm the coils I had been vaping were.

When I put my Evod with a rebuilt coil on my new eGo-V v3 it came up L0 (meaning low Ohms) and won't fire at all. At first I thought maybe the coil was just below the eGo-V v3's 1.2 Ohm cut-off. So I tried building another coil... this time 6 wraps. It gave me the same L0. I have since tried different rebuilds ranging from 2 wraps to 8 wraps using 32 gauge and all are read as low ohms by my eGo-V. I figured the battery was defective until I tried a stock 2.5Ohm Protank head and the eGo-V read it at 2.5Ohms and fired it perfectly.

I've now build more than 10 different coils with different atomizer heads and different wraps and all come back L0. I just don't understand what I'm doing wrong. Especially seeing as I am vaping one of those same rebuilt heads on my standard 1100mAH eGo as I write this...

I'm pretty confused by this so I'm not even sure what to ask, but any input would be appreciated.

Thanks.

 

[steved5600]

First you need an ohm meter to test before you put it on the battery. Next for the Protank type heads save yourself some trouble. You probably did not notice this I didn't originally. But the the coils on the PT heads use a wire called NR-R-NR. Meaning that No Resistance wire - Resistance wire - No resistance wire. Basically it's Kanthal a1 with silver wire on each end. This is so it wont burn the rubber insulator. You can buy this on Discount vapors and Fasttech. Nice thing about them is you can see the resistance wire and you know you wrap that part around your wick. Having said that i calculate your wire (minus leads) needs to be 2.27 in long just for the coil. Not sure how many turns that is. Probably like a 6/6 or 76 wrap. Two other possibilities on the short. Are you sure you clipped back the leads at the bottom all the way to the insulator and that the wires are not sticking out. If not finger nail clippers will do the job. The other possibility is the coil touching the sides or the cap. Also the leads may be touching in the coil.

 

[DavidOck]

The original Kangers didn't use NR-R-NR, and I continue to use straight Kanthal on mine. Just want to be careful to not cook up the grommets, as that will require searching out and getting replacements.

Make sure when you pull the Kanthal through the base that it's not crossed, and the legs are on opposite sides. And as Steve said, make sure they're clipped flush, not sticking out at all. Especially the positive lead that contacts the button of the battery.

Don't overtighten to the battery. Rare, but it's possible to slightly spin the bottom pin, which drags the legs around inside the base and may create a short.

Look closely at the coil inside the head. Make sure it's centered, not touching the cup on either end. (ONce it's put together, hard to tell which end is positive )

I always meter my rebuilds after building, AND after putting back into the base, before putting power to them. And on the battery, if so equipped. Lots of power in these little guys, important to vape safe!

 

[Tom Fuller]

My guess is the the spinning center post. I had this happening with factory coils before I started rebuilding.


Live Long and Vape!

 

[WestonG91]

Thanks for the suggestions.

I think the issue could be the insulators. On closer inspection, it seems most of the ones I have been using are burnt. Although that doesn't explain why a rebuild with a fresh insulator also reads low ohms and won't fire. Unless there is just too much current going to the insulators with this wire. Also don't get why the regular eGo will fire them. Perhaps the new battery has some kind of safety feature that the old one doesn't have?

I also managed to get a couple of brief readings from my new battery. With 5 wraps of the 32 gauge one came up as 1.7 and another at 1.8 for a second or so before bringing up L0.

I have found some resistance - no resistance wire on the website I have been getting my supplies from - Pre Made Resistance - No Resistance Wires x 50

Is that the right stuff? How do I go about rebuilding with it?

 

[Fizzpop]

Protank heads can be tricky to rebuild. My guess is that you have a short somewhere in the works. It is surprisingly easy to have the leads cross below the coil.

 

[Tom Fuller]

That sounds to me like a short. Is it possible the center pin in the new battery is only making slight contact? Hmm odd to say the least.


Live Long and Vape!

 

[WestonG91]

I don't feel like it's a short due to crossed wires, etc. I have rebuilt tens today that all behave the same... plus, I am quite methodical about my coils being just right. It seems like something to do with the behaviour between the wire and the insulator. But I have no idea if it would or how it does cause a battery to not fire instead of just overheating. I don't think it is down to the center pin with the new battery either, as the new battery has no issue with same heads if the coil is stock.

 

[Tom Fuller]

Ok my last guess comes down to amp load.


Live Long and Vape!

 

[WestonG91]

Ok my last guess comes down to amp load.


Live Long and Vape!

It's got me confused anyway. I just ordered some pre-cut 1.8Ohm resistance - no resistance wire, so hopefully that will work. I feel there is some issue with the current/insulator or - like you said - amperage, that the regular eGo is simply ill-equipped to detect. Perhaps that's why the regular eGo is firing yet overheating.

 

[Tom Fuller]

It's got me confused anyway. I just ordered some pre-cut 1.8Ohm resistance - no resistance wire, so hopefully that will work. I feel there is some issue with the current/insulator or - like you said - amperage, that the regular eGo is simply ill-equipped to detect. Perhaps that's why the regular eGo is firing yet overheating.

Yeah I totally missed the overheating symptom! That's too high an amp load!


Live Long and Vape!

 

[DavidOck]

If the regular ego is overheating, it's possibly pushing past it's amp limitations, in spite of the supposed over-current protection that's supposed to be built in. While toppers will get warm in use, especially if chain vaping, the battery should not. Discharging through too low a resistance will ultimately cause a fatal fault. They're only made to handle a specific current drain, but without good regulation can deliver a lot more. Having a potential firecracker two inches from your nose isn't a fun thought...

I think I'd trust the V3 meter, and if you have a separate meter to use, double check. Since your ego batt is "overheating", your coils likely are too low.

 

[Tom Fuller]

I am guessing around a 2-2.2 ohm head would be the low end happy for the ego. Have you googled the specs on that batteries output?


Live Long and Vape!

 

[wheelie]

I had a lot of trouble building with 32 K1 wire. Was having that issue. Switched to 30 K1 and have not had that problem since. Don't think the Proheads like 32 K1 wire for some reason.

Five wraps of 30 K1 gives you 1.7 ohms and 9 wraps of 28 K1 gives same 1.7 ohms so Like 2 wraps of 32 would likely give 1.7 ohms.

Taking a big chance overheating batteries. Always double and triple check before firing. You are likely way over the ohns limit which are burning up the insulators.

 

[BigCatDaddy]

I've built 100's of Kanger coils w/32 ga. A1 wire with no problem. Just make sure you don't cross the legs and that you leave no wire on the outside of them. I take a tiny screwdriver and push the ends of the legs back under the insulator after I cut them off. If you don't, they will short and not fire. If you can feel the ends with your finger after you clip them, they will short. And buy an ohm meter!!

 

[Softrockstarr]

Is your tank making proper connection with your mod? I occasionally have this problem when I take an Evod or Davide off of my ego batteries and put them on my Vamo, sometimes the bottom pin on the coil gets pushed up too far and my Vamo reads it as Low Load. I have to pull it down (gently) a little with a bobby pin before screwing it on and then everything works great.

 

[edyle]

check the coil with the spire off the top of the coil.

I bet the top of the coil wrapps is shorting out on the spire when you put the spire on. Most likely shorting on one side of the coil.

 

[WestonG91]

hey,

I just received the pre-cut 1.8Ohm resistance - no resistance wire that I ordered. I just wrapped it and cut it and my V3 read it at 1.8Ohm right away. Vapes good so far. So simple and easy I think I'll be using this from now on. Still not sure what what was going on with the 32 gauge kanthal builds, though. My guess would be that I was exceeding the amp load like Tom said.

 

[WestonG91]

Thanks for the advice man. I got some pre-cut 1.8 NR-R-NR wire and works like a charm. My new battery reads at 1.8 and it vapes well.

 

[DavidOck]

Glad you found the combination that works for you.

Trust your meter