Black Blade development...

[Obi-Ben]

I think the problem coming up with a workable "black blade" is that people are approaching it counter intuitively. LED blades are at their core...lit by a core LED shining up the hollow tube. But in the black blade, you want something the complete opposite of that, right? So for this to work, you're going to need to come up with a new method of illumination. Here's my idea--tell me if you've heard this one before...

You start out with a smaller diameter clear polycarbonate tube. The inside is coated with a black opaque film or paint. That's your black core. Now around this tube you wrap a diffusing film. This completed assembly is then slid into another larger diameter clear polycarbonate tube. In order to illuminate it, you would need a series of smaller LEDs arranged in a circle pattern so they shine up the clear outer portion of the blade assembly. So when viewed on the side, you would have an effect of a dim center and brighter edges.

Here's a crude illustration of what I'm talking about:




I know it's not perfect, and it's not going to be very bright far from the emitter because there is no reflector at the end so it would have to be pretty short, but I think it would be interesting to see how this looks in practice.

[Sunrider]

I think a black core inside a led string would not work. Whatever is on the higher surfaces of the blade will be seen but anything under that would not. If you mean instead of one led in the blade holder you have say ten? Then if you lined them up with the edge of the blade tube? This would act kinda like a light tube but the sides of light tubes don't emit much light unless diffused. Then when diffused the black core would be lost & light would diminish rapidly down the length. Not to mention placing & powering so many leds would be pretty difficult. It could probably look better than electrical tape tho.

The lenticular lens film is the only way to make a core dark that i can think of.

http://en.wikipedia.org/wiki/Lenticular_lens

You would need to get it printed black instead of the blue in the center of the lobes as shown in this diagram.




Small black lines would be printed along the lens lines where the blue is and would be left clear or something that could pass light like one way mirror where the green & yellow are. This pattern would keep light from being emitted straight off the surface but not at an angle.

This is what is used for those stickers where the image changes when you turn it side to side. So if printed as above looking straight at the sticker it would be black, and if you looked at it at an angle you would see light if there were a source behind the sticker.

[Matt Thorn]

Obi-Ben, the pros and cons of that very idea have been discussed at length here. I think at least a dozen different concepts (ranging from fundamentally flawed to theoretically-possible-but-impractical) have been discussed on that thread, so in order that we not be redundant, we might want to keep this thread on the topic of Senti's blade and use the other thread for more technical discussions. Just my two cents.

[Skottsaber]

I'm sure Lord Maul could do something about this.

DONE. ~LM

[Matt Thorn]

*ahem*

Coming down with something, Skott? I hear Strep Throat is going around. You might want to have that looked at.

[Tyhm]

I think the problem coming up with a workable "black blade" is that people are approaching it counter intuitively. LED blades are at their core...lit by a core LED shining up the hollow tube. But in the black blade, you want something the complete opposite of that, right? So for this to work, you're going to need to come up with a new method of illumination. Here's my idea--tell me if you've heard this one before...

You start out with a smaller diameter clear polycarbonate tube. The inside is coated with a black opaque film or paint. That's your black core. Now around this tube you wrap a diffusing film. This completed assembly is then slid into another larger diameter clear polycarbonate tube. In order to illuminate it, you would need a series of smaller LEDs arranged in a circle pattern so they shine up the clear outer portion of the blade assembly. So when viewed on the side, you would have an effect of a dim center and brighter edges.

Here's a crude illustration of what I'm talking about:




I know it's not perfect, and it's not going to be very bright far from the emitter because there is no reflector at the end so it would have to be pretty short, but I think it would be interesting to see how this looks in practice.

I agree that it would make a dim core, and that it would only work for very short blades - you would have, effectively, 7 light sabers, each 1/4", around a central core. I haven't done a lot of (read - ANY) playing around with blade diameters, but I'm guessing you could get less than a foot of usable light out of that, even with custom optics on each LED. So - maybe possible someday.

I suggested a Finned core ( http://forums.thecustomsabershop.com...&postcount=105 ) might work - perhaps if you made a 3-bladed fin (looking like that car logo, you know the one?) of light-eating matte blackness and fitted it perfectly to a 3-LED board with the appropriate optics, you could get a decent Dim In The Middle, Bright At The Edges blade; then we just need to fine-tune it by finding some sort of filter that makes the brights brighter and the dims dimmer...but it'd be more accurate than the 2d version currently in existence.

The lenticular lens film is the only way to make a core dark that i can think of.

http://en.wikipedia.org/wiki/Lenticular_lens

You would need to get it printed black instead of the blue in the center of the lobes as shown in this diagram.




Small black lines would be printed along the lens lines where the blue is and would be left clear or something that could pass light like one way mirror where the green & yellow are. This pattern would keep light from being emitted straight off the surface but not at an angle.

This is what is used for those stickers where the image changes when you turn it side to side. So if printed as above looking straight at the sticker it would be black, and if you looked at it at an angle you would see light if there were a source behind the sticker.

Oh, there you are! Was looking for you. http://forums.thecustomsabershop.com...7&postcount=90 - they're not as prohibitively expensive as one might ordinarily think...if you can get a dollar store lenticular poster and soak the backing in water/goo-gone/acetone until it's clear, you can at least test the theory for a buck and change; and if it works, you can eBay a full size poster for a modest investment and do the same process, probably get enough to make several sabers. The black stripes might be tricky, but if you have the right kind of feed-through printer you could probably get your computer to do it, or you could print on transparencies and glue them very carefully into place...

[Matt Thorn]

I agree that it would make a dim core, and that it would only work for very short blades[...]
<SNIP>
The black stripes might be tricky, but if you have the right kind of feed-through printer you could probably get your computer to do it, or you could print on transparencies and glue them very carefully into place...

Your above post consists of a purely speculative (and poorly informed) "assessment" of Obi-Ben's idea, and repetition of a purely speculative (and quite sketchy) idea you offered earlier, and have yet to actually test.

You would do well to follow the sternly-worded advice in your own signature. Build some sabers, then share what you've learned with us.

[Tyhm]

Tyhm, you are just full of advice and criticism, aren't you? Remind me again: Just how many sabers have you actually made?
...

Ever hear the one about removing the log from your own eye before trying to remove the mote from your brother's? (Hint: Matthew 7:5 )

We're in a religious debate now?

I was just drawing Sun's attention to an unreplied-to suggestion on his own theory; dunno why you're biting my head off over it. As to the Very Short Lightsaber, talk to Timerender, it took me ages to even get the concession that it'd make any saber at all...and I Did qualify it that I Don't have experience in these matters. Feel free to prove me wrong; I still say the more distance between the LED and the "wall", the longer the effective range of the beam...

The hell, Thorn.

[Sunrider]

As for the lenticular idea it would have to be carefully thought out & professionally printed. It would also be expensive. The most ply able sheet and correct lens shape would need to be used. There are many different kinds of sheet. I'm guessing for 400 bucks you could get a sheet that would make a few blades but idk.

[cardcollector]

Tyhm
Cursing is not allowed here, we all know what you meant when you so rudely typed out your cute little symbols to Matt (who was trying to help you by the way). If you imply a word you might as well say it.

Follow the guidelines please.

I'm beginning to tire of this...