How big does a P7 heat sink need to be?

[Packhorse]

I have a problem.

I have just received a heat sink for my maglite dive light conversion using a P7.
Problem is I have cut the swicth section of the handle out and epoxied it to the light head. Before the handle would thread up further into the light head but now the handle stops at the start of the thread and the heat sink will not quite touch the handle.
The heat sink is a Litemania one.

Its a D maglite
Im using this reflector from DX without the copper base.

and im driving the P7 at 2.8amps.

Can I run it for extended periods? Or will it get to hot?

 

[Drivers100]

I had the same problem. I used a 1" drum sander on my drill press to remove the treads in the head. you'll need to put it all together except for gluing the head and adjust the beam and mark how far in the body needs to go. Use AA to epoxy it.

 

[Packhorse]

Too late. I have already epoxied it. What Im going to do is cut the threaded part off the discarded switch section and thread it in thru the top.

I ran it last night for 10 minutes or so and it seemed fine as is .

 

[Packhorse]

OK I cut off the thread section from the discarded handle and screwed it into the head. I didnt use any grease or glue. The heatsink now slots into the added part again no grease or glue.

I can just reach my finger down thru the tail cap and touch the heatsink which after 5 minutes of running is luke warm.
The 8x AMC7135 driver is very hot though so I may have to sink that.

 

[scott.cr]

The 8x AMC7135 driver is very hot though so I may have to sink that.

I find that these drivers run hot depending on the input voltage. Attach the chip-side of the board directly to the heatsink if you can.

 

[monkeyboy]

I think the M@g head is large enough to provide sufficient heat sinking for a single SSC P7 without needing to also make contact with the battery tube. Just look at the size some of the DX and Kaidomain P7 lights, these have much less heat sinking capability.

What battery voltage are you using? With the 8 x AMC, 3 NiMh cells is usually OK but 4 cells can get extremely hot. The problem is; how do you heatsink something with chips on both sides?

 

[Packhorse]

Im quite happy with the temp of the LED and sink.

The driver boards get mounted in the can not the head so I have glued them both to a piece of aluminium.
Will test it once my batteries charge up (4 xNiMh)

 

[rizky_p]

doesnt have to be really big, even Cree Heatsink works, just make sure all the heat can be transfered to the flashlight body efficiently that is where most of the heat will disipate.