The BOB mod by Todd

http://www.varitube.com/

Some supplies needed:

double sided tape - I use 3M Outdoor rated - backer is bright red.

5 or 6 minute epoxy - I prefer JB Weld as its thick and exhibits decent anti-thixotropic characteristics...ie does not thin and run as it cures :)

Small phillips head screwdriver

Soldering Iron

Solder -60/40 is fine or whatever is available :)

Flux for soldering

Steps:

Chip Test

1) Always test the chip on the bench. I use a battery on which I soldered short leads and alligator clips. Make sure it boots up and functions prior to installation.

Switch Assembly

2) Assemble the switch - Once installed it does not come back out without removing the tact.

-1st screw in the button housing into the box.

- Drop in the button

- cut a very small piece of double sided tape and install it dead center on the tact switch (this prevents switch button rattle)

- Drop the tact switch into the housing and press it firmly to attach the tape to the button.

- now you're ready to epoxy the switch in place. Mix up a little bit of 2-part...don't need much...and dab it on each side taking care not to let any drop into the housing. You want to bridge the tact switch to the housing only,  Let this setup for 10-15 minutes or take your break for the day.

Making the 510 connection

3) The next thing we'll do is make the connection to the 510:

- Remove the connector using a coin and unthread it from the box

- Disassemble the connector by removing the brass cap from the bottom making sure to leave the delrin in place.  Pay attention to not lose the spring and center pin.

- Now feed the White wire of the chip through the box from the inside up and through the threaded hole where the 510 was removed

- Time for some soldering - 1st slide the brass cap from the 510 over the white wire, then slide the spring over the white wire and let them both drop into the box so they are out of the way. THEY NEED TO BE ON THE WIRE BEFORE YOU SOLDER!

- some helping hands are useful for the next step OR use a pair of pliers and place them on the bench and drop the center pin from the 510 into the jaws to hold it stationary while you solder. You are going to solder into the pre-drilled hole.

- place a dab of flux into the hole of the center pin. With a HOT iron heat the pin until you see the flux bubble and quickly add some solder into the hole. DO NOT place too much in there as it will quickly run to the edges which could prevent movement of the pin when re-assembled.

- Take the white wire and repeat the above process. Flux and tin the wire with solder.

- Now reheat the pin and as soon as the solder flows push the white wire into the hole and remove the heat.  Take care that the wire is centered and perpendicular ... standing straight up. Will cool in a couple of seconds.

- inspect your work! Wire should be straight, no excess solder on edges of center pin. Perfect!!!!

- No re-assemble the connector. Push the pin into the delrin, slide the spring and cap up the wire and screw it together. Just snug.

- now pull it all back through from the inside of the box and screw the connector into the box.  Here you can choose to place a dab of thread locker on the top threads only or just tighten the hell out of the connector using a coin.  In either case do not put adhesive on the threads the full length because that is your ground connection to the box!

Most of the hard work is done!!!

Install the chip

Firstly....throw away the clear window...I don't use it and its not needed in my opinion....just takes up space. Also remove the clear screen protector from the chip display.

Now you will need to gently pull and bend and position the wires so they are all kind of out of your way and do not interfere with the chip going in.  Take your time and dry fit the chip and get a feel for the window alignment, etc.

Now I use more double sided tape.  Below the display screen I build up layers of tape until it is about level or just above the display. This allows for the varying levels of the board components while also insulating them from the box and finally most importantly it holds the chip in place while I make final connections and tests before final epoxy in place happens. So go ahead and start working the double sided tape and get that chip in place.

Now do the same thing doe the micro USB...double sided tape and get it fit into the cut out as far as you can and held on for now with the tape.

With the chip in place solder the Red wire to the positive end of your battery holder and the Black to the negative end.

Now look in the little plastic baggie and find the little terminal and screw. Screw that into the cut out in the box up near the 510....securely.

Take a piece of the back wire and make a connection between that ground terminal and the negative end of the battery holder soldering to both...no crimps please.

At this point I like to pop in a battery and make a quick test using the little blue fire button (we'll cut that off in a minute). Pop in a batt and make sure it boots up...scew on an atty and take a quick test that it reads the coil and fires.

Ok Good! Now remove the battery and atty.

Fire Button Connection

Now cut off the little blue fire button that came with the chip. You are going to connect those wires to you tact switch legs. Theres 4 legs. 2 pairs of common so you have to go across the non common legs...just 2 of them...the others can be cut away after you know you made the connection correct. Just look at the switch and you can see the pairs are close to each other so you have to go across the switch for a proper connection. Doesn;t matter just solder 1 wire to a leg and then the other wire the the across the switch (not next to it).

There your about done! Time for another test. Pop in a batt and test the fire button you just connected. Good!!!

Final Assembly

Remove the battery. Now epoxy the board in place. Again using 5 or 6 minute epoxy just a little on each side of the board. Too many people just cover it and they can;t get the chip out should they ever need too. just work a bead down each side for a 1/2" or so...it just needs to be held in place,,,there's no forces ya know?  Let that cure.....but always check winder alignment, etc since you can move it and tweak it still. Nothing worse than a crooked screen :) Also make sure to epoxy in the micro USB. Here I like to add more as the USBs can be a bit tight sometimes and do see some forces from pluggin and unplugging. The key is to make sure its aligned.

Let it all cure to your liking.

Now tidy up the wires. The most critical is the white 510. It needs to be able to move a small amount in and out of the brass cap as the atomizers are installed and removed being spring loaded. Make appropriate bends and curves, and tuck the excess wire down in. You'll get it once you start messing with it. Bend here push there, etc Once satisfied everything is in order install the battery and then the cover and screw it on.

You're done!