Any Commercial Flashlights With DTP?

EDCba · 2018-08-25T11:47:36.000Z

I could have sworn I saw one of the big companies advertising DTP, but I can’t find it again. Nitecore P12GT has “Thermoelectric Separation Technology”. I think the Jaxman E2L has it, any other models?

djozz · 2018-08-25T12:15:11.000Z

Most new flashlights have DTP boards nowadays, even more budget brands like Convoy. It is not really advertised anymore.

eas · 2018-08-25T20:02:30.000Z

djozz:

Most new flashlights have DTP boards nowadays, even more budget brands like Convoy. It is not really advertised anymore.

I don’t think that’s really true. There are a lot of lights with ordinary aluminum MCPCBs. With relatively modern (but low CRI) emitters, ~1000lm off an aluminum MCPCB can be well within the safe operating range.

I just looked through my bin of stars from upgraded lights. A lot of them came from cheap no-name or ultrafire lights, but I’ve also got parts from recent ThorFire, Convoy, and Eagle Eye lights. The only DTP copper MCPCB is from a BLF A6 up upgraded to a SST-40.

One budget light brand that uses DTP in some of their lights is Sofirn. I think all their C8 variants use DTP MCPCBs, along with their newer, higher-output, tube lights, like the SP31 vw, SP32a v2, and, I think, the SP33. I think some of their other lights also have DTP MCPCBs, too.

I’ll add that the most worthwhile mod on many lights is a high CRI emitter. Chances are, any high-CRI emitter you’ll buy already mounted will have a DTP MCPCB. If you are reflowing your own, it doesn’t make much sense not to when you can get a good DTP copper board for $1-2.

Enderman · 2018-08-25T20:25:11.000Z

eas:

djozz:

Most new flashlights have DTP boards nowadays, even more budget brands like Convoy. It is not really advertised anymore.

I don’t think that’s really true. There are a lot of lights with ordinary aluminum MCPCBs.

Just because it’s aluminum doesn’t mean it’s not DTP.

Jerommel · 2018-08-25T21:00:17.000Z

Usually it does mean it is not DTP though.
I assume it is costly to put a solderable layer of copper or brass on the aluminium thermal slug, so might as well get copper to start with.

leaftye · 2018-08-25T21:10:11.000Z

Jerommel:

I assume it is costly to put a solderable layer of copper or brass on the aluminium thermal slug, so might as well get copper to start with.

Other than the center pad, this happens on a copper DTP MCP too.

Jerommel · 2018-08-25T21:13:08.000Z

leaftye:

Jerommel:

I assume it is costly to put a solderable layer of copper or brass on the aluminium thermal slug, so might as well get copper to start with.

Other than the center pad, this happens on a copper DTP MCP too.

You mean the traces? But that has a layer in between base and trace.
To give the alu slug a direct layer of copper, you need another process, maybe electrolyses.

Enderman · 2018-08-25T21:32:30.000Z

Jerommel:

Usually it does mean it is not DTP though.
I assume it is costly to put a solderable layer of copper or brass on the aluminium thermal slug, so might as well get copper to start with.

Why would it need a layer of copper of brass…
Do you think that aluminum can’t be soldered to?

eas · 2018-08-25T22:17:19.000Z

I’ve heard that aluminum DTP boards exist. I’m pretty sure I’ve never seen one.

Sure, aluminum can be soldered to, but that doesn’t mean it’s commonly done, particularly in production SMD reflow. Am I wrong about that?

leaftye · 2018-08-26T05:48:37.000Z

Jerommel:

leaftye:

Jerommel:

I assume it is costly to put a solderable layer of copper or brass on the aluminium thermal slug, so might as well get copper to start with.

Other than the center pad, this happens on a copper DTP MCP too.

You mean the traces? But that has a layer in between base and trace.
To give the alu slug a direct layer of copper, you need another process, maybe electrolyses.

We as a community tend to think aluminum can’t be soldered because virtually all aluminum flashlights are made from 6061, which is very difficult to solder to. 5xxx is even more difficult, but the 1xxx to 4xxx and 7xxx alloys are easier. So the center pad could be aluminum if it’s made from the right alloy, but yes, it could also be built up via copper electroplating.

Enderman · 2018-08-26T06:01:42.000Z

There’s also aluminum wire that’s very common.
Far from impossible to solder it.

Jerommel · 2018-08-26T06:12:51.000Z

But you need special solder to solder to alu.
And special flux too.
And probably higher temperature too.

Firelight2 · 2018-08-26T07:07:51.000Z

Many of the newer premium brand lights ($50 and up) come with copper stars that are presumably DTP. I’ve even come across copper stars on cheap lights. My $10 coast zoomie has a copper star for example.

I don’t think any flashlight manufacturer has ever used aluminum DTP boards though. I know Sinkpad made them, but they were generally a lot less popular … and less effective … than the copper ones.

djozz · 2018-08-26T11:53:22.000Z

I tested the aluminium Sinkpads years ago, and they basically performed as good as the copper ones.

6x 20mm XML-ledboard comparison Flashlight Modding and DIY Parts

[image] 1) common aluminium board, in fact the board the XM-L2 3B led was bought on, from Fasttech. 2) copper board with traditional dielectric layer under the central heatsink-pad, from Fasttech 3) same type of board as 2), but with the dielectric layer removed under the central pad, the gap filled with solder 4) aluminium Sinkpad, version1 (with the shallow gap on the underside of the board where the central pad was punched up) 5) aluminium Sinkpad, version2 (flat on the bottom, the edges…

eas · 2018-08-27T06:53:32.000Z

Enderman:

There’s also aluminum wire that’s very common.
Far from impossible to solder it.

None of which means that its commonly used for joining emitters to DTP stars used in flashlights.

Also, to the extent that aluminum wire is common, it is likely that it is terminated using crimp or screw terminals, just like copper wire.

Firelight2, not all copper stars are DTP, unfortunately, nor do many of the non-DTP copper stars use high-thermal conductively dielectric (electrically insulating) layers.

leaftye · 2018-08-27T07:22:06.000Z

eas:

Enderman:

There’s also aluminum wire that’s very common.
Far from impossible to solder it.

None of which means that its commonly used for joining emitters to DTP stars used in flashlights.

I’m pretty sure that was referring to soldering the LED to the center pad.

djozz, do you recall if the center pad of the aluminum Sinkpads were pre-tinned?