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Nial's Club light design

Here is the list of parts that I used. From RS electronics:

  • White LED w/high dome lens, LXHLMW1D (449-179)


From CPC electronics:

  • 3 x 18650 GP 4.1Ah batteries, GP410LAH1A1P (BT00643)
  • Pack of 20 powerpole connectors (CN03817), clearly you don't need 20 for one light!
  • Various resistors - can't remember what values but you can always get these in Cambridge. A good start would be some 10 ohm ones such as RE5CF10R
  • Black heatshrink 1.2m (for 3 lights) 1.2mm (CB00786)
  • You should also get some tube crimp terminals but the ones I got were the wrong size, so I don't have a part number. You can always get them from Maplins.
  • Some flexible wire would be useful, unless you have some kicking around.


From L2 Optics (google for them):

  • 2 x Luxeon 1 optic holder (OH-ES1)
  • 1 x Spot lens (OP-005)
  • 1 x wide lens (OP-025)

The lenses are so cheap that you may as well buy a selection and see what combination you like.


Battery pack construction

Head Mounted

Cave-proofing the batteries can be accomplished by many means. Potting compound is one option but is expensive. A cheaper method requires

  • self amalgamating tape (Maplins KW29G)
  • plastic battery box from inglesport

The three 18650 batteries can be superglued together and then wrapped in self-amalgamating tape to waterproof them. The sharp edges of the solder tags can puncture the tape and cause it to split. To avoid this, turn the tags inwards when you glue the batteries together and do not wrap the tape too tightly. Optionally, wrap the whole assembly in another layer of gaffer or electrical tape.

Insert the cable from your headset into the battery box and then attach powerpoles to it. Insert the battery pack, and now go push KH.

Belt Mounted

Club lights are traditionally belt mounted. The last round had their batteries cave-proofed using

  • 1 Pill bottle (such as vitamin bottles)
  • Plenty of candlewax
  • 1 ~3.5x1.5cm metal plate
  • 2 Cable ties
  • 1 jubilee clip

Hot glue

The batteries are inserted into the pill bottle, which is then filled with candlewax.

Keeping the cable from pulling the battery contacts was the purpose of most of the rest of the equipment. The metal plate was used to reinforce the flimsy lids of the bottles. The edges were filed off and then five holes (explanation to follow) were drilled using a hand drill through the lid and the metal plate (make sure they line up!). Cable tie the headset cable to the lid and the metal plate using four of the holes, and thread the wires through the fifth hole. Solder the wires on the batteries, fill remaining space with molten candlewax, glue on the lid, and seal the holes with hot glue. Jubilee clip the cable to the side of the bottle so the cable bends 90deg and most of the strain of pulling on the cable is absorbed by the jubilee clips.