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Making a light sabre HELP Answered

Hi I need a little technical help I'm thinking of making a light sabre type thingy so far I have sourced some opaque  acrylic tube a lipo battery and some LED strip  I want to know 1 if what I have sourced will potentially work 2 if not what else do I need .... Here's the tech
1 12v lipo battery 6800mAh, 5meters of 5630 12v led strip this contains 300 LEDs not sure of ampage, I'm crap at electronics but I really want to build this thing and just want a little input to prevent myself from wasting any more cash that I plan on spending
thanks hope I'm not asking to much and I will post the build when it's done and tested


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7 years ago

Hi, I think you posted in the wrong area, but I'll try to help. Had a look at info about your LED strip, not much info but enough. I have included the maths for all this, it is very simple but you can ignore it.

The Power consumption for 5m of strip (300 LEDs) is 72W, that's 6A. 1m of strip (60 LEDs) would be a fifth, 14.4W, 1.2A.

For DC power, batteries and DC Plug Packs -

Power = Volts x Amps . So Amps = Power / Volts

I assume the strip you have is divided into joined sections of 3 LEDs. You can cut the strip at the joins only. If you cut the through one of the sections, that section may not work and you may get a short circuit.

Each section consumes 60mA (0.06A)

When you make up your light sabre just cut as much of the LED strip as you need to fill your tube, just make sure the number of LEDs is a multiple of 3 and cut at the join of the sections.

You will need to connect the + of the battery to a one side of a switch, the other side of the switch to the + of the LED strip. The - of the battery would be connected to the - of the LED strip. SEE THE IMAGE BELOW.

If your switch has only 2 connections just wire those any which way. If it has 3 connections wire the battery to C (common) and the LED strip to NO (normally open). If you wire the LED strip to NC (normally closed) then the switch will work in reverse. More than 3 connections, ask the person your buying it from. Also buy a switch that can handle at least 12VDC and at least the current you will be using.

I would assume that your "blade" would not be more than 1m long. Lets say it is 1m long then you would have 60 LEDs (20 sections) and a current of 1.2A.

If your blade is less than 1m just multiply the number of sections by 0.06A. So a 0.5m blade would have 10 sections (30 LEDS), 10 x 0.06A = 0.6A or 600mA.

Oh, you may want to have twice as many LEDS per length of blade as they will only glow on one side of the strip, so you would fold the longer LED strip over in the middle so you get LEDs on both sides of the acrylic tube.

How long will your battery power last ?

6800 mAh / LED strip current in mA


6.8 Ah / LED strip current in A . (1000 mA = 1A )

So for 1m blade with 20 sections -

6.8 Ah / 1.2A = 5.66 hours.

This is a rough maximum estimate, it might only be about 5 hours.

Things to be aware of LiPO batteries (sorry for the scary bits) -

Don't drain the LiPO battery completely as it will shorten it's life. Better to charge between uses, than let it drop below 3V per cell.

Make sure you have a LiPO charger suitable for your battery, and charge with the correct settings (if you have a charger that has multiple settings).

NEVER charge a LiPO with a charger for other types of batteries (NiCd, NiMh, Lion), a power supply or higher than rated settings with a LiPO charger. The battery pack will overheat and be destroyed, and/or catch fire, and/or explode.

Don't short out the battery, battery and wires can melt, things go bang.

Hope this helps

simple light sabre.jpg