Uhh, how do i assemble one?

I've got the bug to build something again and while i was ordering parts, i felt that i should make something myself too.

So, i'm looking for instructions on assembling a sandwich. I'll likely order the board and whatever from the Shoppe, but don't know what to order to make one for myself, and don't know how to go about it.

Anyone care to help? ELM? /ubbthreads/images/graemlins/icon3.gif

There are some good threads on Wayne's forum. When you order the board, you'll get both pieces (top and bottom) and spacers. You'll need a Luxeon and some AA.

You can get your epoxy locally (he recommends Marine epoxy for the temperature rating).

You can actually speak (chat) with Wayne directly most evenings. On AOL instant messenger he's WaYneY 999 9 and on Yahoo he's dat2zip.

I assume you are talking about building a sandwich for use in a MiniMag. If so, you will need three items - a converter board (Badboy or Madmax), the bare emitter board and an emitter. Good luck finding a nice HD 1W or Lux III device. They seem to be in short supply.

The bare emitter board comes with the spacers. Because it doesn't cost very much, I suggest getting two or three of them. I always seem to have a lot of trouble with them; probably because I'm old and don't care to mod flashlights when I'm sober. From Wayne's site - the emitter board:


As you can see, there is a connection for the emitter cathode and anode. The solder pads are very small. It's best to have a lighted magnifier and vise or modeling clay to hold everything in place. And just because the cathode connection is connected to the emitter board's ground plane, don't assume you don't have do to a neat soldering job. Just the opposite is true. The outter area of the emitter board contacts the lip of the MiniMag and must seat fully for proper heat sinking. The inner area is where the emitter will be seated, so it too must be free of any solder blobs.

(Someone please verify if the following section is correct) - Test your completed sandwich first by connecting leads to the emitter anode and cathode with 3 volts. The LED should light up. If it doesn't, it means it's either reversed, open or shorted. Powering up the completed Badboy sandwich under these conditions will likely destroy the LT1618 chip or schottky diode.

Good luck. And remember, should you or any member of the IMF team be caught or killed, the Secratary will disavow any knowledge of your actions. This thread will self-destruct in 15 seconds.

ELM is correct and I suggest masking the grand plane with something when soldering the connectors. The solder easily flows out of the solder pads. Also, I would suggest soldering from the backside of the board when soldering the emitter leads. This is because, when soldering the emitter, you cannot have the mask on the inner area of the board /ubbthreads/images/graemlins/smile.gif This technique may work for the connectors, but you may not be able to flow enough solder to the hole and pad of the board.

Sorry for not giving you the complete instruction. I'm still trying different procedures each time I build the sandwich to identify what procedure is best for me.

kj - that is a great approach! I'll definitely try it on my next build. The through-hole plating on the emitter board looks quite good, so I would think this should work fine. Once again, just need to make sure the spacers are positioned straight and parallel prior to soldering. Then there won't be any problem connecting it to the converter board.

One other thing - can i use a 5W and power the sandwich with 2x123?

The thermal path is less than dsireable for a 5w at spec.

I just tried kj's suggestion of soldering from the backside. The result is the cleanest looking emitter board I've ever built. Thanks to kj for a great assembly tip.