Rebuilding vivi nova...or not

[thebeingwithin]

i've tried this several time with no luck. i'm using 28 gague wire which may be my problem. i have some 32 on the way. if that's not the issue, i don't know what i'm doing wrong. i use the machine screw coil method. tried 3, 4 and 5 loops. i've done everything i've seen in videos to keep the wires from touching. sorry, i have no pictures right now but i think i'm following the instructions. one wire through the rubber one beside it. the the final metal plug holds the other wire between it and the rubber. i trim both with nail clippers so they are really short and not sticking out. but i have yet to make one that doesn't short. it looks like it should work.

any comments or suggestions?
thanks

 

[LazyBulldogge]

It's a bit hard without pictures of how you've done it.

But:
- Yes, the 28 gauge/AWG could be the culprit, depending on the device you're trying to use it on. 32 gauge/AWG takes 6 wraps (when viewed from the top) to make a 2.4 Ohm coil. If we use Kanthal A-1 as an example, the resistance per foot of wire, is almost 3 times higher on 32 gauge, compared to 28 gauge.
- Make sure the wires don't cross/touch inside the head - the parts that go through the bottom of the head.
- Make sure the end that goes through the grommet (the positive end), doesn't touch the side of the head. The side of the head is the negative end.
- Instead of trimming the wire with nail clippers, try gently turning and turning the wire, it will snap off right where it meets the head after a little while.

Hope you can use some of these pointers

 

[supertrunker]

Once i have the wick/coil inserted - i also pull lightly down on the wires a little - to straighten them before inserting the grommet and metal pin and i also peer down from the top and make sure the coil is not touching either side of the metal holder. I make any adjustments to the top of the coil at this stage by just poking it with a needle.

It also possible to install silver/no-resistance wire to the tails of the coil where they will pass thru the stem, and you can buy crimp on little beads from places like Hobby Lobby for just this.

This is supposed to confine the part of your coil that heats up to the wire above the wire/beads and means you never melt the rubber grommet. In practice i don't use this since it complicates things. Make sure you test your Novas before you use them!

T

 

[Flyer]

I simply do a 3/4 wrap of 33g Kanthal A1 (not excessively tight, nor loose) over 3 strands of bamboo yarn supported by a medium size safety pin. Always twist off the excess leads rather than trying to clip them. Results in 1.9-2.1 ohms every time. All of these other methods likely work too, but seem like a lot of unnecessary complexity. Simplicity works for me 99% of the time.

 

[thebeingwithin]

thanks for the insights. i'll mess with this again when my new wire comes in

 

[thebeingwithin]

maybe i'm confused. 32 gauge is smaller than 28 so how does it have a higher resistance?

 

[thebeingwithin]

ah ha! the culprit was not the wire, nor the process. it was the cheap passthrough i was using. tried one on my ego passthrough and it works!!!!praise be.

 

[Cirrus]

maybe i'm confused. 32 gauge is smaller than 28 so how does it have a higher resistance?

Glad you solved your problem, but I'll answer your question: the 32 gauge is smaller, so it's harder to pass current through it. Think of it as a hose or a pipe. A tiny hose is harder to push water through.