XM-L2 Emitter Mpcb Back Also Connected to "+"???

[Gj1 (Gj)]

@garrybunk

Well my first practice with a reflow was a fail. I used an old dead XM-L on a 16mm star which I did a gas dedome on. I put it in a vise and used my 25watt soldering iron on the bottom. I was able to get the emitter off, but for the life of me I couldn't get it reattached. I'm guessing I need more heat (will probably try my soldering station). I could also try a heat gun, but all I have is a cheap one.

-Garry

A vise is a massive heat sink for a 25W iron to cope with.

Should have ordered the solder paste from RMM.

[garrybunk]

@Gj

@garrybunk

Well my first practice with a reflow was a fail. I used an old dead XM-L on a 16mm star which I did a gas dedome on. I put it in a vise and used my 25watt soldering iron on the bottom. I was able to get the emitter off, but for the life of me I couldn't get it reattached. I'm guessing I need more heat (will probably try my soldering station). I could also try a heat gun, but all I have is a cheap one.

-Garry

A vise is a massive heat sink for a 25W iron to cope with.

Yes, but the only contact with the vise was the thin emitter edge (at least that was my line of thinking).

-Garry

[Gj1 (Gj)]

@garrybunk

@Gj

@garrybunk

Well my first practice with a reflow was a fail. I used an old dead XM-L on a 16mm star which I did a gas dedome on. I put it in a vise and used my 25watt soldering iron on the bottom. I was able to get the emitter off, but for the life of me I couldn't get it reattached. I'm guessing I need more heat (will probably try my soldering station). I could also try a heat gun, but all I have is a cheap one.

-Garry

A vise is a massive heat sink for a 25W iron to cope with.

Yes, but the only contact with the vise was the thin emitter edge (at least that was my line of thinking).

-Garry

But the only contact between the iron and board is even smaller, probably with much less pressure.

[ImA4Wheelr]

You may have been able to reflow back on with some of your flux added (unless you did flux for the reflow).

[garrybunk]

Nope, I didn't add flux.

-Garry

[garrybunk]

WOOHOO! I'm ecstatic! Tested reflowing with a heat gun and the emitter held by "helping hands" instead of the vise. PIECE OF CAKE! I then moved on from a fried emitter (after all I can't test it) to a good working extra cool white emitter. Came right off, went right back on, and it lit up when done! (Checked for shorts 1st.). I still need to reflow the good emitter which is current shorted, but at least I know I can do it now!

So anyone out there scared of reflowing, don't be. If I can do it, many of the rest of you can too! And use a heat gun, way easier than a soldering iron!

-Garry

[comfychair]

I have some small diameter (like around 1/8" or so?) braided fiberglass sleeve that I stick over the jaws on the alligator clips. Anything you can do to minimize heat being sucked away from the star helps.

[JaredM]

If you don’t have one I can’t urge you to get one enough….

Fly tying vise!

Mine is a c-clamp base and I don’t know what I’d do without it.

Building/checking drivers, reflowing, you name it.

Speaking of reflowing, you can call me crazy but I use a propane torch ( and the vise ) and never had a problem. …Except for the last one. Accidental and destructive dedome on a 5a2 XPG2.

[ImA4Wheelr]

Congrats on your new skill, Bunkinater. :)

[garrybunk]

Well I got the emitter reflowed over to a different board. I tried reflowing on the same board, but I still had trouble with it shorting. (Note: I practiced my new madd skillz by reflowing the cool white emitter I swapped off to the old "bad" board and it didn't short.). So with no shorts on the new board I started playing with some new optics I just got in and I accidentally dedomed it! Ugh! Actually the dome is still attached, it just lifts up on one edge, but the tint already shifted. My test setup was direct drive on a large heatsink with a partially depleted 18650 and some thin wires, so it's not like I was direct driving at 6A! Wonder if I weakened it during the reflow?

-Garry