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Author Topic: So, where are folks getting their pixel strips?  (Read 412 times)

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Offline Darkmatter73

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So, where are folks getting their pixel strips?
« on: November 18, 2018, 02:53:58 PM »
I'm jumping in soon, and I'm gonna make a pixel blade now that some of the supporting products are common (connectors and whatnot).
But there are so many options to buy the pixels themselves, I was wondering where the happy medium is on cost vs. reliability?

The plan is to make a 1 in. blade for personal use and testing on builds, and 2 smaller quillion blades for the unfinished Kylo. 
Any pointers before I pull the trigger? =) Any wisdom and lessons learned are welcome.

Thanks
-Darkmatter73

Offline SirRawThunderMan

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Re: So, where are folks getting their pixel strips?
« Reply #1 on: November 19, 2018, 04:51:56 AM »
Well, this is something I've been looking into for my current build, so I'll share what I picked up from shopping for generic addressable LED strips:

There's three models of strips commonly being sold on t'internet, WS2812, WS2812b and SK6812. The WS2812 are older, so they can be found cheaper, but they're really not suitable for duelling sabers. That's because all the data goes through the LEDs in one line, so if one pixel dies, all the pixels above it die. Ws2812b strips are an upgraded model with two data lines, so if one pixel dies, you just get a dead spot on the blade.

WS2812b strips are the most common of the generic addressable LED strips that I was able to find on sale across the internet, to the point where the WS2812b name has become a bit of a generic name for all addressable LED strips. The catch there is that sometimes, you'll find less scrupulous places selling WS2812 strips as WS2812b strips.

Then there's the SK6812 strips, which are a more recent version. The main difference is that while WS2812s have RGB dies for colour mixing, SK6812 have an extra white die to the LED. that die can be either cold or warm white, usually advertised in the listing as RGBW (cold white) or RGBWW (Warm/Walter White). They run the same control software as the WS2812b strips, so you can solder one onto the other with (theoretically) no problems.

Oh, and where possible, try and go for a strip with a white background rather than a black background.

As for buying, I went with eBay, mainly because they were cheaper, and I could buy from a UK seller and have options to return them if things go wrong.  But, if I'm honest, most of the usual saber retailing specialists have strips at a price that's only a little above what ebay was offering (my usual go to, JQ Sabers, was only four or five pounds more expensive than eBay. I skipped them because I would have been crucified on shipping, as I also bought a high drain 18650 to power them)

Folks I know who dabble with addressable LED strips for non-lightsaber purposes pretty much told me to just buy them from alibaba, but the saving in money was offset by long shipping times (estimated ETA, mid December-early January, no returns), and I kinda want to finish my current build before Christmas, as it's my present to myself.

I would definitely recommend not buying the "proper" neopixel strips from Adafruit, unless you have some very deep pockets.

Anyway, that's all I know, hope it helps.
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Offline djmehs

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Re: So, where are folks getting their pixel strips?
« Reply #2 on: November 19, 2018, 09:33:52 AM »
that die can be either cold or warm white, usually advertised in the listing as RGBW (cold white) or RGBWW (Warm/Walter White).

I have to know...are the RGBWW really AKA RGB Walter White LEDs? If so, I'm tempted to buy some on that fact alone.
"Easy is the path to wisdom for those only not blinded by themselves."

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Offline SirRawThunderMan

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Re: So, where are folks getting their pixel strips?
« Reply #3 on: November 19, 2018, 02:11:01 PM »
that die can be either cold or warm white, usually advertised in the listing as RGBW (cold white) or RGBWW (Warm/Walter White).

I have to know...are the RGBWW really AKA RGB Walter White LEDs? If so, I'm tempted to buy some on that fact alone.

No, I'm just mething around. I hope that's crystal clear.

Now if you'll excuse me, I have to hand myself over to the pun police.

Seriously, though, I wouldn't get them. The warm white colour is more of an amber yellow than a white, per se.
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Offline jbkuma

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Re: So, where are folks getting their pixel strips?
« Reply #4 on: November 19, 2018, 03:30:50 PM »
die to the LED. that die can be either cold or warm white, usually advertised in the listing as RGBW (cold white) or RGBWW (Warm/Walter White). They run the same control software as the WS2812b strips, so you can solder one onto the other with (theoretically) no problems.

Not all SK6812 have the 4th color.  The RGBW (WW/NW/CW) are not compatible with the RGB signals.

You can also find SK6812 that are WW/CW/A (warm white/cold wite/amber)

I agree with SRTM. There is no reason to buy from adafruit.  They do not manufacture their strips, and they do not have control over what their Chinese source sends them.  The assertion that they add a layer of quality control for $40 is pure speculation.  If you had to buy 6 strips and 4 failed, you'd still be breaking even against adafruit.  They are a great company that has done a lot for the maker community, but there is no value in buying strips from them.  I have had good luck with Mokungit and BTF brands.

Offline Darkmatter73

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Re: So, where are folks getting their pixel strips?
« Reply #5 on: November 19, 2018, 06:21:34 PM »
Fantastic, thanks all :)

-Darkmatter73

Offline SirRawThunderMan

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Re: So, where are folks getting their pixel strips?
« Reply #6 on: November 20, 2018, 02:42:54 AM »

Not all SK6812 have the 4th color.  The RGBW (WW/NW/CW) are not compatible with the RGB signals.


Wait, they're not? So RGBW strips are no good for saber builds?

Dangit, I've got to return my ebay order when it arrives, then.
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Offline JakeSoft

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Re: So, where are folks getting their pixel strips?
« Reply #7 on: November 20, 2018, 06:12:16 AM »

Wait, they're not? So RGBW strips are no good for saber builds?

Dangit, I've got to return my ebay order when it arrives, then.

I'm just getting into this, but my understanding is that it's NOT that you can't use them entirely, you just have to be aware of compatibility issues you may encounter with the sound board you are using to drive them. For RGB strips each pixel needs to receive 3 data bytes to command the color, RGBW strips will need 4 bytes for each pixel. So, the signals are different. If you are using FXSOS or any open source solution you can probably hack it to work. If you are using "Brand-X" then you'll need to review the user manual to determine if it is possible.


Offline SirRawThunderMan

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Re: So, where are folks getting their pixel strips?
« Reply #8 on: November 20, 2018, 08:23:37 AM »

I'm just getting into this, but my understanding is that it's NOT that you can't use them entirely, you just have to be aware of compatibility issues you may encounter with the sound board you are using to drive them. For RGB strips each pixel needs to receive 3 data bytes to command the color, RGBW strips will need 4 bytes for each pixel. So, the signals are different. If you are using FXSOS or any open source solution you can probably hack it to work. If you are using "Brand-X" then you'll need to review the user manual to determine if it is possible.

Yeah, my current build is another FXSOS build. That said, if you think *I* can hack it to work, I think you hold my hacking skills in a much higher esteem than I do  :tongue:

Right now, my best guess would be replace the WS2812 files in the FXSOS library with RGBW controlling ones, and cross my fingers.
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Offline jbkuma

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Re: So, where are folks getting their pixel strips?
« Reply #9 on: November 20, 2018, 09:29:00 AM »
We've had experiments with fitting RGBW into FX-SaberOS.  In principle it should be possible, but some major modifications it will be tough to stuff in the extra RAM requirements under the hood. It won't be as simple as swapping the libraries, there will need to be a lot of changes through out the code, since ever storage, recall and and assignment is setup for RGB.  You may be able to alter the existing library to accommodate RGBW, but only a few libraries support it by default so it would require even more changes if you moved to, for instance, the adafruit neopixel library, which will also carry more overhead. The code overall might be able to be optimized better to free up some RAM but those who have set out to do so haven't accomplished it yet.

Offline SirRawThunderMan

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Re: So, where are folks getting their pixel strips?
« Reply #10 on: November 20, 2018, 09:40:08 AM »
...So, swapping my SK6812 RGBWs with WS2812bs it is, then...
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Offline JakeSoft

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Re: So, where are folks getting their pixel strips?
« Reply #11 on: November 28, 2018, 07:37:29 PM »
We've had experiments with fitting RGBW into FX-SaberOS.  In principle it should be possible, but some major modifications it will be tough to stuff in the extra RAM requirements under the hood. It won't be as simple as swapping the libraries, there will need to be a lot of changes through out the code...

I so wanted to say "hold my beer" to this, but I've got my hands full already with other projects.  :tongue: haha

Offline jbkuma

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Re: So, where are folks getting their pixel strips?
« Reply #12 on: November 29, 2018, 06:39:10 PM »
Saber Republic made a RGBW version of FX-SaberOS that works great with 4 LED stars, but there is memory issues running the pixels.