Attn: atomizer rebuilders

[kinabaloo]

So the connections are taking between 0.3 ohms and 2 ohms.

Heat generated in the legs is more or less wasted.

But good to see your progress Well done!

[crazyhorse]

I checked out two meters so far and find they both measure 0.5 ohm resistance within themselves and their leads. I suppose this means the coil resistance figures should be reduced correspondingly to 3.7 and 4.0. This resistance is still very high. It seems like I remember reading something about coiled nichrome exhibiting higher resistance but I can't find it now. All I can find is a disclaimer on a current/temp chart that says it's valid only for straight wire stretched horizontally in free air.

When the atomizer is jumpered by plugging in 20 gauge solid copper, there is an indicated reading of 0.1 ohm. I'd say all this means a net resistance of 0.2 ohm attributable to the nicr/copper cap tube connections. This should drop with a better fit and the proper conductive paste.

There will always be heat loss from the legs but it doesn't seem to be much at this point. IR shots taken of the cap tubes remain below 85° F during 10 second bursts. The tubes got warm to the touch during the extended burn test but I didn't get the temperature.

When I get closer to dialing this in for a practical use, the heat loss should be similar. There will be much less leg in the sockets (up to 2 mm) but they will be a tighter fit with better thermal conductivity.

The next obstacle will be getting my paws on the smallest cap tubing. Albion Alloys in Bournemouth, Dorset is the best candidate I've located so far. They make it as small as 0.90 mm OD but they haven't answered an inquiry I sent on 6/29.

If anyone has any info on coming up with a small quantity of very small capillary tube, your help will be greatly appreciated.

[kinabaloo]

Contacts often have a resistance of around 0.5 ohm and it's difficult to get lower (which is why i like to use a touch switch and not a mechanical one).

[crazyhorse]

Small diameter copper capillary tube may be impossible to obtain. Unfortunately, it's apparently not produced in the US where you can actually communicate with manufacturers. None of the f's in UK, China or India will answer an email, even when it's routed through an intermediary like Global Sources.

This brings me to Plan B. Hypodermic needles. These will be much more difficult to work than copper. They're brittle stainless steel but what can you do? At least they're conductive and available in a variety of diameters. These particular needles are 0.87 mm OD. Slightly smaller than the smallest copper cap tube on the planet. It should be up to the task with a good hi-temp anti-corrosive conductive paste like the SS-30.

The coil is another one made out of 32 AWG and a little more carefully and tightly wrapped. Again, it's 3½" around a more orderly little bundle of grapho-glas wicking. It reads an adjusted 3.5 ohms with the needles and 3 mm of legs inserted into each pole. When powered up it starts going red within a second. The coil is actually heated bright red in this picture but it doesn't show up that way. Must be the flash.

I'm thinking it may be a challenge to "solder" this stainless steel tubing to the battery connector without completely melting down the 4-hole system. Anybody have any thoughts on this? Eh, never mind. That ain't gonna happen.

[kinabaloo]

Small diameter copper capillary tube may be impossible to obtain. Unfortunately, it's apparently not produced in the US where you can actually communicate with manufacturers. None of the f's in UK, China or India will answer an email, even when it's routed through an intermediary like Global Sources.

This brings me to Plan B. Hypodermic needles. These will be much more difficult to work than copper. They're brittle stainless steel but what can you do? At least they're conductive and available in a variety of diameters. These particular needles are 0.87 mm OD. Slightly smaller than the smallest copper cap tube on the planet. It should be up to the task with a good hi-temp anti-corrosive conductive paste like the SS-30.

The coil is another one made out of 32 AWG and a little more carefully and tightly wrapped. Again, it's 3½" around a more orderly little bundle of grapho-glas wicking. It reads an adjusted 3.5 ohms with the needles and 3 mm of legs inserted into each pole. When powered up it starts going red within a second. The coil is actually heated bright red in this picture but it doesn't show up that way. Must be the flash.

I'm thinking it may be a challenge to "solder" this stainless steel tubing to the battery connector without completely melting down the 4-hole system. Anybody have any thoughts on this? Eh, never mind. That ain't gonna happen.

Great photo !

The pot with the holes wont melt - it's ceramic.

Any worry this paste might get into the vapor?

Interesting work you're doing

[crazyhorse]

I'm not worried about the ceramic pot. That doesn't come into play at all. The conductors will simply feed up through the holes in it just like the original wires.

The 4-hole thingy I'm talking about is the silicon-rubber looking area in the battery connector that surrounds the the positive power pole in the 801. Little jets in this connect to the vents underneath the collar. It lies beneath the points where the standard 24 gauge power wires are soldered to the battery connector. This silicon is also the thing that insulates the power pin from ground.

As I mentioned earlier, the SS-30 has a working temperature of 1800° F, it's ~30% copper and the MSDS doesn't show any particular toxicity at all. The only thing I can definitively say right now is... I don't know for sure.

[kinabaloo]

I'm not worried about the ceramic pot. That doesn't come into play at all. The conductors will simply feed up through the holes in it just like the original wires.

The 4-hole thingy I'm talking about is the silicon-rubber looking area in the battery connector that surrounds the the positive power pole in the 801. Little jets in this connect to the vents underneath the collar. It lies beneath the points where the standard 24 gauge power wires are soldered to the battery connector. This silicon is also the thing that insulates the power pin from ground.

As I mentioned earlier, the SS-30 has a working temperature of 1800° F, it's ~30% copper and the MSDS doesn't show any particular toxicity at all. The only thing I can definitively say right now is... I don't know for sure.

The rubber grommet should be ok.

[crazyhorse]

I'm hoping a dip in zinc chloride flux with 96% tin and 4% silver will do the trick but I may have to tin the needles with something nastier. If I have to use a torch, the outlook is grim.

[kinabaloo]

I'm hoping a dip in zinc chloride flux with 96% tin and 4% silver will do the trick but I may have to tin the needles with something nastier. If I have to use a torch, the outlook is grim.

I'll have to think on this one ...

[crazyhorse]

It looks do-able with phosphoric acid and the 96/4 @ 430° F silver solder. If all else fails, I can easily solder a solid 20 gauge copper pigtail to the needle. I know that works. In fact, the best plan may be using only a short needle socket attached to the wire. This will eliminate the flexibility and brittleness problems of the stainless.