stacking batteries in the plain 3.7v mod

[jumper]

Is it possible to use two batteries in the plain 3.7 mod? I wanted to make a big version where I could stack two 18650s. This is the copper tube version and not a box.

thanks

[methos]

You can use 2 18650's if you run them in parallel (I think that's spelled right) 

[jumper]

Don't mean to be dumb, but how do you do that in a tube mod?

[methos]

You would have to run 2 tubes. If you stack them one on top of the other they would be in series and double the voltage. You can do it but you would need to run a board (TI or OKC) to bring the voltage down to 3.7

[jumper]

You would have to run 2 tubes. If you stack them one on top of the other they would be in series and double the voltage. You can do it but you would need to run a board (TI or OKC) to bring the voltage down to 3.7

Darn, I was hoping I could do it in one long tube. The first time I ever saw a "pimp stick", I knew I wanted one... well at least until I found out the price. Seems to me that if they can make a tube mod with 2 18650s then there has to be a way. Probably would be some electronics involved (something I don't know about yet, lol).

[FlameOut]

Can you tell me why you would want a 7.4v - 8.4v output on your atty?
If you were a 7watt vaper you would need a 7.8 ohm to 10 ohm atty.
A 10 watt vape you would need 5.5 ohm to 7 ohm atty

[CraigHB]

Run them in series and use a regulator.  It's really quite simple to wire up one of the Murata OKR regulators.

http://www.mouser.com/ProductDetail/Murata/OKR-T-6-W12-C/?qs=%2fha2pyFaduh2WQLU0PDa8lp%2fyb8n3MJSf1kIZ9dvbr4%3d

http://www.mouser.com/ProductDetail/Murata/OKR-T-10-W12-C/?qs=%2fha2pyFaduiffsVHBt9VRMG4xsP9iEwyyeQnI92WuJk%3d

[methos]

I'm gonna try the OKR in a mod soon. Which one do you recommend Craig the 12/6 or 12/10?

[CraigHB]

If you use the the 10 Amp regulator, you can run a sub-Ohm atomizer if you ever want to mess around with it.  Dual coil rebuildable atomizers can often end up with resistances under an Ohm. 

The 6 Amp regulator is good for just about anything in a more typical resistance range an Ohm and above.  It's only a difference of $2 so I would just buy the 10 Amp regulator.  Better to have it and not use it than want it and wish you had it.

One of the nice things about using that particular regulator is since it's a switching regulator, it conserves power.  Higher input voltage translates to less current loading on the power supply.  Amperage demand on the cells is cut in half since voltage is double.  Very cool since it gives you a wide option of cell types to use.  Cells with a 6A drain would be perfectly adequate to take the regulator to its output limit.

[jumper]

I've been gone most of the day because we had a protest against animal abuse at our rabies control facility. Thanks so much for the info Craig and Methos. I do believe that this will be my first try at using some electronics in a mod. A mod that used two 18650s would be awesome.

And Flameout, I'm not looking for that kind of voltage. I don't have anything that could take that kind of power. I just want an all day vape setup with the possibility of having a few more volts. My sweet spot is about 4.2  volts and I would never go over 5. I have some Novas that are about 3ohms but my favorite tank is the iClear 30 and it's 2.2ohms. For me, perfect at 4.2 volts.

Thanks a bunch for the links Craig. When I get my money at the first of the month I'm going to get some of the items you talked about. Seems like this would be a great way to start learning something about electronics in my plain mod. Wish me luck 

[FlameOut]

Good luck jumper on the okr build. You may want to consider using shorter batteries like the 18350 stacked. The 18650 stack would be very tall for a practical tube mod.

You mentioned an all day vaping time. Stacking batteries is series. It doubles the voltage and the amp hours stay the same. With parallel batteries the voltage stays the same but the amp hours will double. So.... parallel will give you more vaping time.

[methos]

If you use the the 10 Amp regulator, you can run a sub-Ohm atomizer if you ever want to mess around with it.  Dual coil rebuildable atomizers can often end up with resistances under an Ohm. 

The 6 Amp regulator is good for just about anything in a more typical resistance range an Ohm and above.  It's only a difference of $2 so I would just buy the 10 Amp regulator.  Better to have it and not use it than want it and wish you had it.

One of the nice things about using that particular regulator is since it's a switching regulator, it conserves power.  Higher input voltage translates to less current loading on the power supply.  Amperage demand on the cells is cut in half since voltage is double.  Very cool since it gives you a wide option of cell types to use.  Cells with a 6A drain would be perfectly adequate to take the regulator to its output limit.

That is some interesting info there on the batteries. I agree for $2 it better to have it and not need it. Thanks again Craig!

[jumper]

Good luck jumper on the okr build. You may want to consider using shorter batteries like the 18350 stacked. The 18650 stack would be very tall for a practical tube mod.

You mentioned an all day vaping time. Stacking batteries is series. It doubles the voltage and the amp hours stay the same. With parallel batteries the voltage stays the same but the amp hours will double. So.... parallel will give you more vaping time.

Thanks for the "good luck" I'll probably need it, lol. I get nervous about working with something like Craig linked to. Puts me in unknown territory. I've just got to where I can crank out the plain 3.7v mod with the soldering working the first time. Soldering was a big hurdle for me at first, but I have it down now.

Have you ever seen a "pimp stick"? They ARE big, but look very cool IMO. Maybe not practical, but cool.

[jumper]

Run them in series and use a regulator.  It's really quite simple to wire up one of the Murata OKR regulators.

http://www.mouser.com/ProductDetail/Murata/OKR-T-6-W12-C/?qs=%2fha2pyFaduh2WQLU0PDa8lp%2fyb8n3MJSf1kIZ9dvbr4%3d

http://www.mouser.com/ProductDetail/Murata/OKR-T-10-W12-C/?qs=%2fha2pyFaduiffsVHBt9VRMG4xsP9iEwyyeQnI92WuJk%3d

Thanks so much for the links. After what you said I will go ahead and get the 10. When I get them I'll probably have to ask for help. Once I find out how to do the first one, I shouldn't have any problems in the future using it.

[CraigHB]

If you're using clearos in the 2 to 3 Ohms range jumper, the 6 Amp OKR regulator would be more than adequate.  I only recommend the 10 Amp regulator in case you ever want to mess around with a very low resistance.  You might at some point, it's pretty popular to do multi-coil builds on rebuildable atomizers, I've done a few myself.

You mentioned an all day vaping time. Stacking batteries is series. It doubles the voltage and the amp hours stay the same. With parallel batteries the voltage stays the same but the amp hours will double. So.... parallel will give you more vaping time.

That's actually incorrect, charge capacity and thereby run time adds for both series and parallel cells.  What you state can be true for an unregulated load where power consumption is a function of voltage, but that's not the case for a mod using a switching regulator that conserves power.  For a long winded explanation, see this post.

[FlameOut]

Yes, I was referring to just battery voltage and not a regulator

[jumper]

Forgive my ignorance about these things, but would the OKR give me the ability to have vv? I really would like to get the volts up to 4.2... I'm reading the specification on the chip, and they mention a watts range, but I'm not sure about these things.

[CraigHB]

With the OKR, you set the voltage output with a "trimmer" resistor.  You can use a regular resistor to set it to one particular voltage or a variable resistor to make it adustable (VV).  It's quite simple, just two connections, one to a pin on the regulator and one to electrical ground.

For DC, Watts are simply voltage times current.  So, when they say 50W for the 10 Amp regulator, that means you can use any voltage times current that's 50W or less.  For example, you could run 10Amps with 5V or 8 Amps with 6 Volts.  So there's two limits, maximum is 10 Amps or 50 Watts, whichever comes first.

[jumper]

Thank you Craig. I was hoping that it was doable. And thanks for the info about the resistors. I would probably like the one that would allow vv. How do you set the volts? Is there something you turn on the OKR? How does that work?

One more thing, can you give me a link to the vv resistor? I would appreciate that. If it helps, like I said, I would never go over 5 watts.

edit: I think I understand about the trimmer (some). Would you have to take the mod apart to change the volts?
edit2: I heard somewhere that some things will automatically adjust for ohms. Does that resistor do that?

[CraigHB]

Here's a link; 1k trimmers

They always have 3 leads, but you only use the center lead and one of the outside ones.  The leftover one can be cut off.  The outside lead you chose determines the direction you turn the adjustment screw for voltage up and voltage down.

If you mount the trimmer pot so the adjustment screw is accessible, then no, you don't need to take the mod apart to adjust voltage.  You could just put a small hole in the side of the mod to provide access to the adjustment screw with a jewelers screwdriver. 

You can alternately use a pot that accepts a knob to provide a dial in the side of the mod; 1k Pots

The last question you posed makes no sense to me.

[jumper]

Sorry about the last question. My limited knowledge shows. But thanks for the info. I will understand more when I actually see the resistor. And that's great about being able to get to get to the to the trimmer without taking it apart. I'll try my best to do it that way.

I might be asking too much too soon, but how do you get the trimmer to stay where it's accessible? Would you have to use some sort of epoxy? I looked at the "pot" style you linked to and it's hard to tell, but do some of them use a small nut to hold it in place?

Thanks for overlooking my lack of knowledge in this area, but once I know how to do it, I might actually be able to help others like you have helped me

[CraigHB]

Well, in electronics you nomally mount stuff like that to a circuit board then mount the circuit board to standoffs using screws, but that's not practical for an e-cig mod.  For my own mods, I've managed to come up with a box design that's all press fit except for the atomizer connector which uses a nut.  So, I don't have recommends for you on that.  I know some of the guys use an epoxy to mount things.  There's a thread in this forum talking about the best epoxy to use.

[jumper]

I've been looking at the pots and have noticed something. There are usually two types shown when you enlarge the picture. They show one that has the pins come straight out from the bottom and one where the pins go down. I would think that I want the one where the pins point downward.

I know I'm asking a lot of you Craig, but can you give me a link to the ones that point downward so I know I'm getting the right one. I'm just about to pull the trigger on these and want to make sure I get the "right" parts. Plus, when I look at the PDF they still show the 2 different types.

thank you.

edit: this is the pot I'm looking to get: http://www.mouser.com/ProductDetail/BI-Technologies-TT-electronics/P160KN2-0QA25B1K/?qs=sGAEpiMZZMtC25l1F4XBUzVC3q8S9Qb8Ddkl4RQpnBY%3d

extra note: Sorry if the about message is just plain dumb. I just don't know about these things yet.

[CraigHB]

Actually, you know what, you should use the circuit Breaktru just posted here;

http://breaktru.com/smf/index.php?topic=907.msg8963

It's a little more complicated, but it's the best circuit to use.

In that case, you want a 200 Ohm trimmer and a 220 Ohm resistor.  You should also get a resetable fuse.  It's really not complicated even with a couple more parts. 

That pot you linked to is pretty big if you look at the dimensions.  It's best to use a multi-turn trimmer pot.  There's a pretty big difference in size.  The down side with the multi-turn pots is it's less convenient to change the settings all the time, but you would typically find a setting you like and leave it there.

Give me a few minutes and I'll get some links up for appropriate parts for you.

[jumper]

That's great Craig. You don't know how much I appreciate it. I already have the fuses. I got the ones that Breaktru suggested. However, I have yet to use one. Got a bunch though.

[CraigHB]

Trimmer Pot

Resetable Fuse

Resistor

Heat Shrink Tubing

[jumper]

Thanks so much for the links. I just want to be sure I'm getting everything, so let me do a check...
Fuses and tubing I already have so here's whats left to get.

1. trimmer pot
2. resistor

and I have a question about the OKR board... when you say use the circuit that Breaktru uses in his other post, are you just referring to the wiring that he shows? At first I though it was another board, but when I looked at Breaktru's subject line, he's still talking about the same OKR boards. His is different looking though so I'm a little confused about that, lol.

If you could verify the parts we've been talking about, I will go ahead and order them.

thanks again!

[jumper]

After working hard to try and understand everything, I just placed my order for the parts. Thanks for all your help Craig. Unfortunately, I will probably have to ask other questions when the parts get here, lol.

appreciate your help so much!

[jumper]

I have another question about the OKR-T/6-W12-C board. On the specs, it says that the output current on channel 1 is 6A. My C&K push buttons are rated at 3A. Does that mean that I will have any issues with the C&Ks?

thanks.

[Breaktru]

The Output max is 6A for the OKR-T/6. You are using the 3A P.B. on the input. The input spec is 2.69A at full load and I doubt you will use full load.

The C&K is rated 3A @ 28vdc. At 8.4vdc (2 series batteries full charged) the amp rating is actually higher then 3A.

A step down regulator has a higher amp output than the input.
A boost regulator has a higher amp input than the output.

[jumper]

Thanks for the reply. Glad I'm not in trouble with the P.B. And thanks for the info!