How to wire tri-cree to Obsidian

[ChillyAleman]

Howdy all. I recently decided to upgrade my stunt saber. I am going from bare minimum to a new Tri-cree, obsidian and I bought a 1000mA buckpuck for good measure. I know there are plenty of diagrams and helpful tips on the site, but I wasn't sure if they applied to the tri-cree. Is it as simple as Li-ion Batteries - Buck Puck - Obsidian - LED? Or will I risk not having enough amperage to fully power all three LEDs?

[Sarich Belmont]

If you are wanting to wire a tri cree so that all three dice are firing at once, I would not recommend a buck puck for the install, as you will seriously be limiting the current to the LEDs. I would skip the puck, use resistors and run it with a single 18650 with a high amp drain, at least 4 amps. I do have a couple diagrams, but I am at work at the moment, so it may be a bit before I can answer.

[Kouri]

I think something that gets missed about buckpucks is that the current gets divided when LEDs are wired in parallel - so a 1000mA puck on a normal 6-7.2v battery pack is only going to to supply each diode in a Tri-Cree with ~333mA of power. You'd either have to use three pucks with a high-current battery pack, or run the LEDs in series with a battery pack capable of providing the combined voltage of three LEDs + 2.5v to run the buckpuck - meaning, three or four lithium batteries in series. Good luck fitting a 4x AA battery holder in a US hilt...

[ChillyAleman]

Alright, I have never taken an electrical engineering class nor physics, but I'm not stupid and I know the basics. I know that if the current is constant, then the voltage is lowered by the resistors. If the voltage is constant, I can use resistors to increase the amperage. SO, my question is, is the voltage constant in this circuit or or is it the current? Or does it change before and after the obsidian board? I have Trustfires, but I'm not opposed to spending an extra 10-20 to get some 5A batteries from Amazon.

http://www.amazon.com/MicroMall-3-7V-4-2V-5000mAh-Battery-Charger/dp/B00NV16J6Y/ref=sr_1_1?ie=UTF8&qid=1443500743&sr=8-1&keywords=18650+batteries+5000mah

I already have a dummy cell, so I could use them in an AA pack and use the dummy to make sure I don't have 2 in line. I'm not sure if these would fit in an AA pack though. I think they are half an inch too long. Or I could get the the rechargeable Panasonic pack from one of the other guys, but I think I may have to wire an in-hilt recharge to get those recharged.  

TL;DR
When I resistor trustfire Li-ions, is the voltage constant, meaning I can get more amps out of it? If not, Should I buy an 18650 from Amazon or another vendor? Can I easily recharge 18650s from another vendor? How many amps can an Obsidian Board take?
I also ordered a Stunt Aeon v2 with 4AAA with a tri-red. Would I also need to upgrade these somehow, or will they be resistored for maximum brightness by US?

[ChillyAleman]

After looking around for a bit, I think I will buy some Panasonic 18650s from Amazon. They have high ratings and deliver 3400 mA, leaving about 1133 mA per LED, which should be within its tolerance. I am also looking at a Nitecore I4 intellicharger, which also has decent reviews. I might buy some bigger wires (16 gauge can hold 3 amps? or is that too clunky for a saber?) and an 18650 battery holder from Amazon. I already have lots of resistors, and I have the obsidian and tri-cree on the way. I'll see if I can separate the US speaker from the pack. If not, I'll either buy a 28mm or 20mm speaker as well. Are there any problems with this?

http://www.amazon.com/dp/B00C26OWGS/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3GU0YX45WYV44&coliid=I34IDLITZBFOSW
http://www.amazon.com/dp/B00KBFZDI8/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3GU0YX45WYV44&coliid=I149W1QHKBE5XZ
http://www.amazon.com/dp/B00FGX8NVO/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3GU0YX45WYV44&coliid=I2WBJ44EKUUOCD
http://www.amazon.com/dp/B00R5SDGCE/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3GU0YX45WYV44&coliid=ITHEKAX96SJ9J&psc=1

Also, since Amazon isn't a rival saber company, they are okay to mention right? If not, I promise this is my last post about them.

[Sarich Belmont]

Go for the Panasonic. They are top notch and have a high discharge rate.

Don't get real thick wire. 16 gauge is way too thick for sabers but you will be just fine using 26-28 gauge wire. That's what many smiths use.

[Kouri]

Be careful there, as mAh is a measure of the storage capacity of a cell, not its maximum current output. That said, a simple rule of thumb is:

Good 14500 cells (Genuine Trustfire) can discharge 3.7v @ ~2A.
Good 18650 cells (Panasonic) can discharge 3.7v @ ~4-5A.

A single 18650 will have no problem running all three diodes in a tri-cree, but you might suffer a volume reduction from your Obsidian board if it's not fed more voltage.

Two 18650s will have a heck of a time fitting inside a standard US hilt, and they definitely won't do it side-by-side with a soundcard stacked on top. For space-saving and maximum audio volume, you might need to stick with the two 14500 cells in the standard battery/speaker holder.

With an efficient driver, the 7.4v @ ~2000mA coming from the 14500 pack might be able to output the 2.65-3.7v @ 3000mA needed to run a Tri-Cree. Will a set of resistors be enough to accomplish this?

I don't know.

You'll have users arguing there's no way 14500s in series can run a tri cree full-blast. You'll have Emory popping in saying the setup runs fine. I don't have a tri-cree saber to hook my multimeter onto. Maybe the reason tri-cree sabers aren't lots brighter than the single-crees is because each LED is only running at ~700mA instead of the full 1000mA a single would be operating at.

[ChillyAleman]

You guys have been extremely helpful. I'll be giving out some points. Final question:
Does this mean every electronic I have connected will be running at 3 amps if I get an 18650? For example, If i were to wire in a standard accent LED or when I wire in my speaker, will it be able to take all of those amps? Would I assume the accent is getting .020 Amps or 3.4 amps?

[Sarich Belmont]

You really need to get the variables for your LED and powersource and plug them into a resistor calculator, like this: http://led.linear1.org/1led.wiz

For an accent LED, just use a DynaOhm resistor. That'll run it at the 20mah that it needs to light up.

[Kouri]

The idea would be to have a separate resistor on each LED. You'd want each LED in your tri-Cree limited to its forward voltage (3.4v for either of the blues, 3.7v for green, and 2.65v for the warm colors) and a max of 1000mA. Not sure what accent LED you're using, but you'd want a resistor between it and the power source that'd limit the juice to its own preferred voltage and current.

I personally have been making plenty of use to that same resistor calculator Sarich posted above.

Use 3.7v or 7.4v as your Source Voltage, depending on whether you're using one or two cells. Lithium batteries spend most of their charge around 3.6-3.7v. Fully charged, they're about 4.2v, but that doesn't last long, and the Crees can survive being slightly overdriven for the short time before battery voltage drops.

[Kouri]

Chiming back in with a workaround to the 14500 current limit. 7.4v is enough to run a couple of Cree LEDs in series - just barely meeting requirements for green, and plenty of wiggle room for the other colors.

Using green as an example, instead of running three 3.7v 1000mA LEDs in parallel, you could wire two up in series - so essentially one 7.4v LED and one 3.7v LED - That way you'd only need 2000mA to run the star, rather than 3000mA.