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BhujangiJedi
01-26-2008, 01:11 PM
I finally got my parts and put my sabers together, but I feel like there's something wrong... if you look at my sabers (http://forums.thecustomsabershop.com/showthread.php?p=74345#post74345) they make the rest of the ambers in the gallery look rotoscoped in comparison.

I'm using 4 x 1.2V NiMH AA with a 1.2 ohm 3W resistor. The one on the right is understandably dim with low batteries (which I have since charged, but the improvement only meets the level of the blade on the left).

It blows me away looking at the first two posts in the amber gallery, by Hajime and Artifical_Lynx - the pictures in a lit room show blazing bright sabers! Mine looks OK in the dark and barely perceptible in a lit room.

I am using "TCSS style" battle blades and plan on getting some poly wrap to put inside, but while illumination evenness will improve, won't the brightness be even slightly less than the current underwhelming level of brightness?

Lord Maul
01-26-2008, 01:21 PM
It probably has to do with the exposure settings on each camera. Hajime's and Artifical Lynx's are probably overexposed a bit, while your aren't. That would make a difference in brightness.

Clockwork
01-26-2008, 05:40 PM
Xwing has a youtube video on why you get dimmer LEDs with Resistors, that might be part of your problem if you think it isn't bright enough.

http://www.youtube.com/watch?v=IG9hfzYIn_Q

vortextwist
01-26-2008, 05:50 PM
the CSS battle blade is what it's named for, dueling, not show. get an ultra blade and it will be significantly brighter.

Lord Maul
01-26-2008, 05:54 PM
Better yet, get one of Xwing's Nylon blades. They are hands down THE brightest saber blade out there.

BhujangiJedi
01-26-2008, 06:18 PM
Countless hours of dry-eyed forum reading and $60 worth of blades and now I hear the TCSS blades are dim?!

Is there a driver that will work with 4 X 1.2V NiMH AA? The shop says the 1000mA buckpuck has a min input voltage of 5V. And you need to use a potentiometer with the buckpuck?

...and if I'm really being cheap, could I maybe bring my LEDs to the electrical engineering lab at the university, have some kids figure out what resistor works best with my specific LEDs, and then go with that?

Lord Maul
01-26-2008, 06:22 PM
The TCSS blades are for dueling. That is why they're called battle blades.

You don't need a pot with the buckpuck, and Corbin's board works with a 4.8V pack.

xwingband
01-26-2008, 06:24 PM
True, but to be honest Amber is a pretty weak color. Properly driven it's still not a good color.

If you want a yellow color I'd recommend a powerful white LED and a yellow filter. Yellow actually is a great filter.


Xwing has a youtube video on why you get dimmer LEDs with Resistors, that might be part of your problem if you think it isn't bright enough.

http://www.youtube.com/watch?v=IG9hfzYIn_Q

B5813
01-26-2008, 07:43 PM
I wouldn't personally worry too much that it's a TCSS battle blade versus something else. I too was rather underwhelmed when I first ignited my creation. After viewing many threads on led blades I did insert several feet rolled of celophane inside but I also sanded the inside of the blade. With fresh batteries that blade lit up bright AND even. I think you'll really notice a difference of just the added wrap inside the stock issued film for sure! With my experience of doing the two mods I gave the blade absolutely did not lose brightness as a trade for even lighting!!

Hasid Lafre
01-27-2008, 01:37 AM
As far as the blade is conserned. get a mirror in teh tip, and about 3 foot of polyP, cellophaine or ultra film. Then put it inside the diffuser tube and hot glue it in place.

Thin is me tcss thickwalled blade.

Dark room

http://i204.photobucket.com/albums/bb168/Sidneyious/Lightsaber%20Pics/SD530359.jpg

Partly lit room

http://i204.photobucket.com/albums/bb168/Sidneyious/Lightsaber%20Pics/TCSSstyleBladewithPolyPinlitroomnof.jpg

Dark Helmet
01-27-2008, 02:24 AM
pics can be misleading, here is a pic of my lux v cyan from my phone... it looks perfect, but it's nowhere near real life, it looks completly fake, but my junk razr camera freaks out from the light exposure giving a stunning effect. this is the main problem when basing your build on pics from the forum, this is why tim asks for full info on your pics, i.e., camera, flash, lighting conditions etc....this was taken in full light, 3x 100 watt bulbs in my kitchen http://i230.photobucket.com/albums/ee44/darthdouchebag/226331655_756568634_0.jpg

Hasid Lafre
01-27-2008, 02:32 AM
Yeah but my pics are as close to what it actually looks like off the pictures.

BhujangiJedi
01-27-2008, 07:47 PM
I went to the comicon in Phoenix today (anyone else?) and there was a guy there with 2 stunts from Ultrasabers, 1 red and 1 blue, and they lit up very nicely in the fairly well-lit indoor area.

It sounds like I may be able to improve my brightness by improving my power source, but is there any way to do so cheaply? I'm already stretching it with the $250 I've spent on these when I would have been 85% satisfied with two $80 stunts from Ultra... but I just had to be able to join them together, so I went with MHS. I'm not too interested in Corbin's board because it does way more than I need and costs a bunch. I currently have a 4 x AA battery holder, and no space to spare at all in my hilt. I don't want to use alkaline AAs, since that's wasteful and I already have a bunch of NiMHs that I may as well use. With 4.8V supplied, is there a driver I can use that will work better than a resistor? I would really appreciate the ability of the driver to deliver improved brightness even with low battery power as it's annoying to have the blade get dimmer as the batteries get low. Does the 1000mA buckpuck really require 5V minimum... or can you squeeze by with 4.8?

Lord Maul
01-27-2008, 07:50 PM
You can probably squeeze by with 4.8V.
Remember, a 4.8V pack when fully charged puts out more like 5.8V

Eandori
01-28-2008, 06:13 PM
Ok, time to clear up some misconceptions here. Lay out some facts.

- Small electronic components do not always work to spec. It's HIGHLY reccomended that you do some testing with your specific luxeon LED's, and a current/voltage meter to find out what your specific LED wants. Just like Xwingband pointed out, a 2.95v rated LED might require 3.4v to actually get up to the 1.5 amps it wants.

- In Xwingbands video he showed a red Luxeon III requireing 3.4v to get up to 1.4 amps. That is within spec... note that the spec says the "forward voltage" is 2.95v and the "MAXIMUM current" is 1.5 amps. You are not expected to be running maximum current at the typical forward voltage rating. That would have been called "MAXIMUM FORWARD VOLTAGE."

Here is a link to the specs of that Red Luxeon III.
http://www.luxeonstar.com/item.php?id=1770&link_str=196::198&partno=LXHL-LD3C

- 4.8v of supply is WELL ABOVE enough voltage to drive a luxeon III red. The amber LED has the same rated forward voltage and current. I suspect that the problem is not the battery, or the resistor, or the LED. Just the value of the resistor. It's too resistive.

- As long as your battery voltage is decently above the FULL FORWARD voltage of your LED then your battery is big enough to get your Luxeon bright. As a side note to this, your battery must still be above the LED voltage WHILE it's putting out the required current "called UNDER LOAD".

=================== LETS DO SOME MATH ==========================
Ok, so lets assume a 4.8v battery will be around 6v unconnected and 4.8v under a 1.5 amp load. You need to measure your battery to ensure this... but for now I'll assume that.

Source = 4.8v
LED forward Voltage = 3.5v at 1.5 amps
Drop across resistor = 4.8-3.5 = 1.3v
Resistor value for optimal current = 1.3v/1.5A = 0.866667 Ohms.

So... you were using a 1.2 Ohm resistor. And for 1.5Amps you needed a 0.866667 Ohm resistor (as close as you can get to that value). Your resistor was too big! That will make your LED dim because it's restricting too much current.

THAT IS YOUR ANSWER.

A buckpuck gets around that problem by taking in a voltage that's higher then the output voltage needed, and regulating the current at a certain value. So a resistor setup is NOT "dimmer" then a buckpuck. At full charge they are just as bright as each other. The difference is as the battery dies, it's voltage drops, and your resistor will not drop value along with the battery to match. So... you saber with a resistor starts bright but then dims.

Cheers.

BhujangiJedi
01-28-2008, 09:09 PM
I went from the resistor chart (http://www.thecustomsabershop.com/resistor.aspx) which shows me needing a 1.2 ohm resistor for an amber Lux III with 4.8V (4x1.2V AA NiMH). The resistor chart also lists the lumens of the different LEDs... does lumens not relate much to brightness? Comparing the 110 of the amber to the rest of the LEDs, it seems like amber should be fairly bright. However, Ultra lists (http://66.216.78.205/help_answer.asp?ID=157#157) amber as the least bright of their Lux III's.

With the resistor, my sabers don't start bright and get dim, they start dim and get dimmer. :(

Pushing this "simple" project over $300, I ordered some 1000mA buckpucks, so we'll see how I fare with those. At least I won't suffer dimming blades as the batteries die and will be able to easily swap out for different LEDs.

xwingband
01-28-2008, 09:15 PM
True, true... not everyone has the ability to try out each of their LEDs but it's worth noting. I certainly wouldn't use a resistor without checking it. I want my LEDs to at least start at close to the max value and that's what I was trying to show.