How do sandwiches run w/o headsinks?

How is it that the sandwiches sold by the Shoppe run without heatsinks, just the circuit board? Am I missing something here?

The heatsinking is what transfers from the top edge of the board to the lip on the host that it's in. The original design MM and BB don't create a problem at 400 - 500 mA. It's the MM+ and others upward of 800+mA that get quite warm. Some think that those that run the beefed up sandwiches will suffer a shortened LED life. The general concensus is not to use LUX3 in a sandwich driving it at 1A or more (in a minimag or Brinkmann). I have some of the beefed up sandwiches and I'm careful about not running them for extended periods. When they go, they go.

The top of the sandwich is also a ground plate that makes contact with the flashlight body. Heat is transfered though the thin plating to the body of the light. I was kinda skeptical at 1st, but it does seem to work pretty well as long as you have a good contact with the body.

I was 'playing' the other night with my Mini-Mag with the BadBoy400. (It's O.K. to play with them, right?) I fell asleep and the Mag ended up between the sofa cushions. I think it was on for about an hour, and I have to say it was quite toasty. Not too hot to handle, just plenty warm. The whole thing, including the AA alkaline cells. Guess I should be lucky that it wasn't a 5 watt device.

(Hell, I'm destine to burn in eternity anyway. May as well go with my lights on).

Since the whole mini-mag got toasty, that's a good sign that the sandwich is successfully transferring heat to the flashlight body. Since the light was stuck between sofa cushions, it was insulated from the air and probably warmed up a lot more than it would in normal use.

The pcb at the top of the sandwich is copper clad. The LS sits on top of the copper, and has a bit of Arctic Silver undr it to help thermal transfer. The heat is transferred to the copper clad, which then transfers the heat to the lip of the flashlight body. It's actually pretty effective.

How about the sandwiches itself? Does it get warm? I was thinking about using a BB to drive luxeons in a vehicle. The luxeon will not be physically bonded to the sandwich so I wondered does the sandwich by itself get warm? Does it need to be heatsinked as well?

The BB400 or BB500 sandwiches would get warm. It shouldn't get hot though. The Luxeon will need to be heatsunk. Be careful the car body is negative biased. If you use amber or red Luxeon, you will need to isolate the heatsink from the car body. White Luxeons are OK.

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hotbeam said:
The BB400 or BB500 sandwiches would get warm. It shouldn't get hot though. The Luxeon will need to be heatsunk. Be careful the car body is negative biased. If you use amber or red Luxeon, you will need to isolate the heatsink from the car body. White Luxeons are OK.

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So I can use the BB500 without heatsinking the sandwich. How about BB750 with Luxeon 3watt, do I have to heatsink the BB750?

reef,

Sure as long as you pot them completely in AA (Artic Alumina)

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reefphilic said:
I was thinking about using a BB to drive luxeons in a vehicle.

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Am i missing somthing here ? a vehicle already has 6/12VDC, why not use that ?
1)you never need to feed it.
2)you dont need to buy the board(buy more LS's instead)
3)you can make the LS take whatever current you want with a simple $1 resistor.
to name a few...