2AA Box / Opposing Mag Switch / Mega XXL Carto / Charging Port

[Rader2146]

-1/2 Hex Nut ground down to fit and center reamed for 510 connector. (I think it is a 5/16-16 nut but it was just one I had in the misc nuts bin. The important measurement is the 1/2" outside dimension) -3mm x 3mm Round Neo Mags. -Section of BiC pen to hold the mags. -8-32 Machine Screw and nut for switch plunger. -DC Jack for onboard charging: PJ-040DH CUI Inc | CP-040DH-ND | DigiKey -Designed for Mega XXL Smoketech Cartos: Smok Tech Dual Coil Mega XXL 1.5 OHM Cartomizer, Black or Smok Tech Dual Coil Mega XXL 1.5 OHM Cartomizer

 

[Rader2146]

Im not sure why, but all the formating has been removed and I cant edit. So excuse the jumbled paragraph in lieu of a bulleted list.

 

[DonG]

Do your magnets actually create the connection? Been contemplating a similar switch but thhe magnets i have seen used were in place of a return spring and not actually providing an electrical contact.

 

[Robert T]

Nice compact mod!

 

[Rader2146]

Do your magnets actually create the connection? Been contemplating a similar switch but thhe magnets i have seen used were in place of a return spring and not actually providing an electrical contact.

Yes the magnets complete the connection inside the tube. Neo mags are nickel plated so they do have good conductivity. I flattened the long battery contact from the 2aa box and placed in so that it makes contact with the nut. Then placed one mag on the other side of the contact and superglued the pen tube to the contact. Then placed the other mag in the tube and run the screw through the nut. The only solder connections on the switch mechanism are at the small nut and the large nut. The only area of concern is the contact made by the screw to the first mag. I did my best to make the screw flat at the connection, but it wouldn't take much error to go from full contact area to only a pinpoint contact area. It's a little weak with a TF 14500 but, I think that is the fault of the battery and not of the construction. I have some IMR's in the mail that should wake this thing up.

 

[Rader2146]

Nice compact mod!

Thanks. It pockets very well and the mega carto is great for my "always on the go" schedule at work.

 

[asdaq]

Nice one, I always like to see more use of magnets in mods. The problem you mention with the 1st screw could be fixed if that screw/nut were ferritic, then it would always have good contact. One thing I notice is that the case could use a sleeve for the screw to pass through or a tube over the screw's thread's so the action is smoother.

 

[Rader2146]

The action in obviously adjustable, and I usually set it around 1/16". With that small amount of movement I haven't had any problems with the threads catching the case. 1/8" or more....if gets a little rough. I looked for something easily available to use as a sleeve, but many hours at 2 hardware stores and a hobby shop turned up empty.

You say ferritic, as in containing iron? I plan on replacing the screw with a brass button-head rivet and threading it only as far as needed to set 1/16" of movement. I assume this would be opposite of your recommendation of using ferritic materials?

 

[DonG]

Good idea. The solder joint on brass will be more secure too.

Something i do not know: will the constant passing of electrical current through the magnets cause them to deteriorate and loose force over time?

One of my concerns in a switch like this is the soldered wire is attached to a moving part so constantly stressing that joint. Maybe the minimal travel renders that concern as minimal enough to not worry about.

 

[Rader2146]

From what I've read about neo mags is that the current isn't an issue. Heat, however, is an issue. I have a couple of 6x3 discs that I soldered wires to for charging batteries. They work, but have lost probably about half of their strength.

I had to change my wire routing for the reason that you state. It was a more direct line and the wire broke just before the joint. Now with the half loop it is working fine with no signs of stress.

 

[asdaq]

Rader, yes something the magnet wants to stick to. The screw could be zinc coated steel (standard hardware store screw) and the nut brass. The zinc is rather crap and you'd want to replace it every so often, but it would be simpler than trying to get 304 or 306 SS screws. I saw digikey has nickel plated #6-32 screws but I think they are brass.

For a sleeve, a very small length of brass tubing would do well, K&S Engineering makes 3/16" and 13/64", one of these should fit the screw. A little loose is fine, you can jam a strand of copper wire inside to keep it snug.

These magnets are sold as battery spacers too, so current isn't a problem, heat yes.

 

[Rader2146]

Well I got the AW IMR's in the mail today. After a full charge there was no change in the performance. I getting 3.2v at the connector, 3.4v at the screw, and 3.6v at the small nut. I don't think I'm getting good enough contact between the nut and screw, and also between the screw and magnet.

 

[Lethalp]

Nice lookin lil stealth mod for those big ol honker cartos!