Introduction: Eclipse Torch 1W.
This project is one of my most successful home-made torches yet... a 1W pocket-sized torch capable of producing almost as much light as a D-cell Maglite! (such is the power of LED's today). The Eclipse mint tin is the perfect enclosure for a torch ... conveniently small, yet can hold 2 AA batteries plus the required components, and even has a flip top 'battery compartment'.
It cost me about AUS$50 to assemble, and has seen almost constant weekend use in my other hobby of exploring underground tunnels, so has withstood rigorous use for nearly two years. It puts out an amazing amount of light for a torch its size, and it runs for over two hours on a set of Ni-MH rechargeable batteries.
Note that it contains no heatsink... this hasn't been a problem as of yet. The LED runs at about 1W, and although it does get warm, seems to run well without heatsinking. If you are concerned about this, and somehow find a way to fit a heatsink into the design, let me know!
A short history... after building a torch with a Tic-tac box, I thought about using an eclipse tin to build something bigger and much brighter, and found to my delight that the tin fitted 2AA batteries perfectly. The first build had a rocker switch on the top of the tin (hence the rectangular hole) but was unreliable and kept switching on in my pocket. The toggle switch on the front solved this problem.
I have had this torch for nearly two years, and it has been one of the most reliable I have ever owned (and I've had a few cos I'm a torch nerd).
I hope you find this instructable useful! I built this torch some time ago well before I thought of posting it up online. Therefore, the photos have been taken after the build process, and may not be as 'instructable' as they should... if I ever make another Eclipse torch, I'll replace the pics with better ones...
Step 1: Parts.
Components you will need:
1x Eclipse mint tin in the colour of your choice.
1x Cree XR-E 3W white LED module. (I got mine from www.cutter.com.au)
1x Optic and holder to suit Cree LED.. I used a 10 degree beam spread. (www.cutter.com.au)
1x Luxdrive MicroPuck 2009A-SHO (500mA). (www.cutter.com.au)
1x mini-toggle switch. (any electronics shop should have these)
1x 2AA side-by-side battery holder. (any electronics shop)
Heatshrink tubing for wiring insulation. (electonics shop)
Drill and appropriate drill bits
Side cutters (for cutting out the large hole for the optic)
Adjustable spanner for mounting the switch
Electric heat glue gun
Step 2: Drilling Out the Tin.
The only work you need to do to the tin is to drill two holes - one large one for mounting the optic, and a small one for the toggle switch.
The large one is problematic, as it needs to be about 15mm or 9/16" diameter - larger than any drill bit I had. I solved the problem by drilling instead a series of smaller holes, around the circumference of the desired hole size, and cutting it out with side cutters. It doesn't matter if the hole looks messy - it will later be concealed with glue anyway.
The small one is just for the toggle switch, and only needs to be the diameter of the mounting shaft (in this case, 4mm or 3/16"). Positioning is important here... the centre of the hole should be 7mm (1/4") from the corners of the box, so it will be offset from the centre. (this is to facilitate the positioning of the micropuck under the switch)
Step 3: Solder the Components
Putting the mint box to one side for now, solder the electrical components together as per the wiring diagram. The idea is to get everything soldered before mounting it all the box. I used a DPDT switch and wired both the positive and negative through the switch. This isn't necessary electrically, but it keeps things tidy within the mint box. Use heatshrink tubing on the switch contacts to help with durability and reduce the risk of shorting out on the metal box. Make sure that the length of wire between the switch and the battery holder is longer than twice the length of the box (you may need to use extra wire and heatshrink tubing). This extra wire will make it much easier to pull the AA holder out to change batteries.
Step 4: Insert Components in Tin.
Push the components into the tin while observing the following:
-the LED should align with the large hole. You may need to file down two sides of the aluminium LED mounting to fit it in the tin, as its diameter is slightly larger than the tin height.
-the switch should align with the 4mm hole, and its off position should be facing inwards as per the photo. This orientation makes the torch much less susceptible to being switched on accidentally.
-the LuxDrive micropuck should fill the gap between the switch and the bottom of the tin.
At this point the switch can be screwed into place with the mounting nut supplied.
Step 5: Mounting the Optic.
First, test the optic's fit to the hole. The rim of the optic should sit about 4mm (1/8") proud of the rim of the mint box. Adjust the hole size if required. Once that's done, snap the optic to the LED inside so it is attached but hanging loose on the tin. Then apply a generous amount of glue the whole way around the base of the optic, and press the optic to the tin while the glue cools (shouldn't take long).
Step 6: Finished!
So there you have it... a pocket-sized torch that is bright enough to make people go 'wow' whenever they first see it! I have added velcro to the bottom of mine, and to the top of my bike helmet, so it now doubles as a bike light! Although I've only used it this way a couple of times, it hasn't fallen off... yet.
When inserting the battery holder, it's best to keep the end with the wires toward the rear of the torch i.e. up against the flip door. This will save strain on the wiring at the switch.
The LED module will become quite hot, particularly after constant use. This is normal, and hasn't given me any trouble yet.
You can expect about 2.5 hours from a good set of 2500mAH rechargeable batteries. It will also run well on alkalines.