Rebuild of Melo3 TC Ni/Ti not working properly (iStick Pico 75W)

[stamasd]

I made sure none of the coil turns touch, they are very evenly spaced and far apart by at least 0.5mm between turns. For instance the coil pictured above has 9 turns spaced over 12mm total. I've been making coils for many years (not only for vaping but for my ham radio equipment - KC1BJW)

As for the outer wire, you don't see it in the pictures but the end was actually tucked under the insulator, and only popped out when I removed the post. I'm quite sure it wasn't touching anything it shouldn't have. When I built the coil, after I installed it in the casing I pushed that end with tweezers under the insulator so that it was pinched between it and the metal casing, not sticking out like that.

 

[mcclintock]

I get an issue sometimes with my Pico that there will be a lack of connection that normally the voltage would burn through the oxide or whatever preventing contact but instead the mod thinks it's hot and protects (although in wattage mode this would sometimes cause excessive voltage and hit). You really have to have good connections.

Sounds like there is no contact to the Pico's ohmmeter or circuitry, somehow. With the Ti you can at least try it in watt mode at a low setting as another test. The Melo is designed to screw down all the way (match) vs. some atomizers you can't, so if you shortened something the Melo might not contact.

 

[Imfallen_Angel]

From the first picture, I'd say that your positive (the inner wire is a bit too long and is probably touching the negative walls as you screw it it.. it really needs to be trimmed at the very edge of the insulator.

And are you certain that the negative (outside leg) is the one that was coming down from the top of the coil... I found that if you inverse them, it will throw the reading.

And are you certain that you have enough cotton between the coil and the leg that's coming down? (and then rolled around it after) If the cotton isn't thick enough, it won't insulate that leg very well.

 

[BrotherBob]

Let me start by saying that I've rebuilt my Kanger coils for a few years and I never had any problems doing that. I have tools, wire, cotton, ohmmeters etc.
Recently I thought I'd graduate into the higher league and start using a TC mod. I got myself an iStick Pico kit with Melo3 tank, used it for a little while with the EC coils and it's been working fine. I decided to rebuild one of my used coils into a TC Ni and/or Ti coil. I watched videos, done a lot of reading, seemed simple enough. Got some Ni200 and Ti wire, both in 28ga. I started with a nickel build, did 14 wraps on 4mm diameter like the original Melo Ni coils have, checked resistance - was around 0.12 ohms, good. Wrapped it in cotton, installed back in the coil case, checked resistance of rebuild coil - same. (BTW I use 2 separate ohmmeters to check, a coil ohmmeter and a separate precision multimeter). Placed coil in the tank base, checked resistance again, still good. Assembled the tank, put liquid on the coil and in the tank, screwed it in the Pico. Switched the Pico to TC mode, it doesn't work. The battery says "no atomizer" - it doesn't detect it. Checked assembled tank resistance again, it's still what it should be. But the battery will not recognize the coil/tank. Replaced the coil with a new prebuilt one, it works. Put my rebuilt one back in, it doesn't work.
I rebuilt that coil 2 more times, with new nickel wire in various resistances (once 0.15 ohm, once 0.22 ohm). None of these was recognized by the battery, same error "no atomizer" despite the coils and assembled tank checking fine with 2 different ohmmeters.
I then took a new coil, took it apart before it was even used, made a titanium build of 0.5 ohms (9 turns 28ga on 4mm). Again it checked fine with ohmmeter. Again the Pico says "no atomizer".
I'm obviously doing something wrong, but I can't figure out what. I would appreciate any help I can get.

Welcome and glad you joined.
First thing I would do is to try tank and coil on another mod within the ohm capacity of your coil. I would need to determine if tank or Mod is at fault.
Could also try three additional avenues of inquiry for faulty unit:
Local Vape Shop -----Might be simple.
Vendor who sold it ---see if they will repair or replace or advise (any authorized distributor).
Manufacturer contact ---see if they will repair or replace or advise.

 

[stamasd]

Thank you all for your replies. I did quite a bit more reading and testing, and I think the problem is not with the coils I'm making, but with the Pico itself. In short, I think I have a counterfeit device that seems to work fine with basic coils, but not with TC coils. I'll have a way to prove this in a few days when I receive a guaranteed authentic Pico (from that store that advertises as "no clone zone"). The one I have has developed some problems over the past few days, including display corruption that occurs regularly after a few hours of use, and as mentioned above is not recognized by firmware updaters such as the manufacturer's or ArcticFox.

(I got the one I have from a seller in China through Aliexpress - I figured the Chinese wouldn't counterfeit their own devices, but apparently I was wrong)

 

[Imfallen_Angel]

Well, that's "good" I guess that you figured it out.

A few people on here have mentioned possible clones of the Pico, odd as it's sucha cheap mod to buy anyways, but I guess anything to make money using cheaper parts I guess.

You should look at FastTech as it's quite reliable.. if it's a clone, of anything, it will state it and if it states authentic, then it's the real deal.

FastTech - Gadgets and Electronics

I've already purchased for them a couple of dozen times by now and while people rag about the shipping time (and it CAN be really bad once in a while, but quite good other times (Worse I had was 5 months as it got lost and detoured, 2 for one, and 1 month for another, the rest have been about 2 weeks, sometimes less (10 days has been regular lately)), between their prices and service, it's hard to bear them.

 

[Continuity]

If you're in most countries, choose the 'ePacket' shipping option at Fasttech - my last order cost USD$0.90 extra for it, and was only 4 days in transit to my door in the UK.