PC v3.5 LED wiring

[daaguilar]

Just a quick question about the resistors. Any help would be appreciated.

I want to use a Blue/Blue/White Cree XP-E2 CopperNova
I want to run both the blues as the main and the white as FoC

I'm assuming I won't need a resistor for the white because I believe the manual said that it has a resistor built in to the v3.5
Please correct me if I'm wrong!

My main question I suppose is, what to do with the two blues?
I've seen through the forums that it is safer to wire them separately as opposed to in series, calculate the resistors separately. Safety sounds great to me!
In any case. Here's my math.

Ohms=3.93 rounded up to 4
Watts=3.93 rounded up to 4

I keep thinking there's something wrong with that but I kept to the formula, so I don't know.
So 2 4ohm 4w resistors? One per blue?

I'm also wondering if, although separately is safer, would it be easier to just wire them in series?
And if I did so, would that mean a 1ohm 2w resistor (0.46 & 0.46 rounded up to 1 & 1)?

Lastly: Whether I wire them in series or separately, because that would just dictate the placement of the resistor(s) (right?), how would the actual wiring work? Just a Y off of the positive and negative on the board suffice? Or is their a more proper way to do that?

I've only done a fairly basic upgrade on an Ascend from Madcow so I'm still pretty new, hence all of the questions.
I have scoured the forums to no avail.
Thank you in advance for any and all help!!!

[Bark]

The Petit Crouton requires more voltage than the Nano Biscotti. Typically, the Petit Crouton is run with 7.4 volts. Since this is greater than the sum of the two colored LED dies' forward voltage, you can run them in series. This is recommended because it will extend battery life.

Also you have it backwards. On the Petit Crouton, the main LEDs are power regulated. Run the mains in series with no resistor(s). The Flash on Clash is NOT power related, so the FoC white LED die is what needs the resistor. The source voltage for FoC is 7.4 volts. The manual says to install an SMD resistor on the pads, but I recommend that you just bridge the pads and have an external normal resistor attached to the wires. The white has a forward voltage of 3.15, so you'll want:

(7.4 - 3.15)/1 = 4.25/1 = 4.25 ohm (minimum - round up) resistor that can handle...
4.25*1^2 = 4.25*1 = 4.25 watts (minimum - round up)

So if you go with this battery (http://www.thecustomsabershop.com/74v-Li-ion-2600mAh-18650-Battery-Pack-P699.aspx) (or any 7.4-volt battery), you'll want to wire in this resistor (http://www.thecustomsabershop.com/47ohm-5w-resistor-P492.aspx) for FoC.

[daaguilar]

That was incredibly helpful, thank you so much for clearing that up for me.

Last two things would be that as a rookie solderer, I'm not entirely sure on how to wire the mains in series or how to bridge the pads for the FoC. Happen to know of any tutorials or threads that go into any detail on either subject?

[Bark]

Madcow has some helpful videos on YouTube. Just look for the Custom Saber Shop channel.

To wire the two mains in series, you first need to identify them. It's fairly easy, as two of the dies will look the same, and one (the white one) will look different. Arrange the orientation of the LED board so that the two similar ones are centered as you look at them. You will run one positive wire to the positive pad on the outside of the two dies. Then, run one negative wire to the negative pad on the outside on the two dies, on the other side from the positive wire that you connected in the previous step. Next, connect the positive pad and negative pad in between the two dies, the ones right next to each other, together. (Some people just connect it with a bead of solder. Some people connect it with a little bit of wire. I use a little wire, solid not braided.) Then, connect the positive and negative wires to the main pads on the PC 3.5 board. Since the mains are power regulated, no resistor is needed.

(PC Main LED Positive Pad) --- <wire> --- LED#1 Positive Pad --- (LED#1) --- LED#1 Negative Pad --- <wire> --- LED#2 Positive Pad --- (LED#2) --- LED#2 Negative Pad --- <wire> --- (PC Main LED Negative Pad)

To bridge the SMD pads for the FoC, refer to the directions to find their location. Then, just get a length of bare wire that spans the gap between them, and solder the wire to both pads. I just used the wire going to the FoC LED and stripped enough on the end to span the gap. Remember to have the resistor somewhere on the wires going to the FoC LED though.

I recommend that you watch some YouTube videos concerning soldering in general until you feel comfortable. Make sure you have an ESD safe soldering iron that can get hot, a small tip, and try to keep the time you contact the iron to be as little as possible. (A hotter iron won't take as long to melt the solder.) Then, practice practice practice. My final recommendation would be to solder wires together and resistors and wires together first before you solder LED or PC boards to get the hang of it.

[daaguilar]

Thank you so much, you have answered all my questions. It'll be a month or two until I can even purchase the board but I plan on heeding your advice and spend that time learning as much as I can, especially when it comes to soldering.
Again, thanks for all the help. I'll be sure to post any other questions that I might have.

[Bark]

May The Force be with you.

[daaguilar]

As I said before, I still won't be getting the board for another month or two but I'm not very patient. Decided to do a runthrough of the wiring for my future saber.
http://i577.photobucket.com/albums/ss213/thejugglingninja/lightsaber%20electronics_zpsfwrqdmiu.png
Comments or concerns?
Again, thank you in advance!

[Forgetful Jedi Knight]

It looks fine.

[daaguilar]

That is very exciting to hear, thank you very much.

[Bark]

The next thing to remember are the config files. With your setup, you will want to comment out the color profiles in the override file.

[daaguilar]

Thank you for that last bit of advice, I'll be sure to check back once I actually get the board and wire everything up. I have at least finally started ordering the long list of parts I'll be needing. So far, the chassis parts and shroud material but soon I'll order the rest. Definitely excited to finally get this project going!