Experiments with Thrunite TN31

XM-L2 U2. Highest bin and cool white.

Yes. But the original tint didn't look like 1A to me. It was a bit warmer.. For a non-tint-snob 1A would be good though. ;)

And buy it with copper star, preferably SinkPad. The original star is big, heavy, and made of copper. You don't want anything worse than that.

Reflowing the new emitter to the original star is also a good option.

Great Info! How'd you get the TN31 open? Heard it was difficult - glued maybe?

Dedomed XP-G2 sounds like a great option, can't wait to see the results.

Glued, yes. But opens up quite easily with two of these:

You have to wait for de-domed XP-G2 results.. I just destroyed one when de-doming it (which was weird: bond wires are intact, but the led doesn't light up), so I'm not in the mood of trying with another - at least without further thinking / investigating why it failed..

I got a similar strap wrench I used opening the 7G9 which was LockTite'd, but it wasn't so easy, had to use a heat gun and a vise and still screwed up the aluminum housing somewhat from the torque in the vise - cut right through the layers of Gorilla Tape. Your wrench looks better though, and having two has got to be a better approach then one and a vise... Thanks!! May be giving it a go at some point.

Ohh, bad news about the XP-G2, ouch! Did you use gasoline? Only tried it once and it worked well, but on a XML U2.

I opened mine by using boiling water and diping it inside a bag for about a minute and strap wrenches

No, heat. Still not sure what went wrong. I was happy with the looks of the emitter, but decided to test it before soldering it in and it just didn't light up.

I need to consider gasoline for the next one, at least if I can't figure out what went wrong with this one..

It's funny, not much info around on mod'ing the TN31 or other big name brand lights, but maybe it makes sense because the buyer of those lights wants power/quality out of the box, and even as a modder, I have 2nd thoughts of opening up an expensive device. My 7G9 with an XM-L2 U2/SinkPAD is brighter than a TN31 and throws about the same, and now that I got my hands on a TN31 and see how bigger the reflector is, there is definitely more potential there, as you are starting to see.

I have 20mm copper SinkPads. I hope they are compatible with the TN31.

Sure they are. But you need to center it by your own. The original "star" is 32mm x 2mm.

Here's my two attempts for de-doming XP-G2

1.

2.

Yes. They look "ok", but don't work => failed hard, need to buy more of these (and wait)

LFMF: Next time will be gasoline, most probably. :)

Think maybe the heat method de-soldered the emitter? You probably thought of that. Could try reflowing one for the heck of it.

Those look much better than the ones I dedomed and they work alright, strange...

2nd experiment added.

Note that the emitter might not be 100% functional*, but the results are still good.

(* I managed to break it during de-doming and fix it with conductive paint. Now how's that for frugal? :)

I used Bison Electro (quite expensive, but lasts "forever" in my use):

I prepared the emitter by scratching the positive metal visible near the bond wires. After that I added a small drop of paint next to both bond wires, making sure they connect to the positive plate.

Then I allowed the paint to dry properly (24h) and tried the emitter.. And it worked!

Next task was to reflow it to SinkPad:

That will work until I get next XP-G2 to try de-doming again. :)

I got the SS bezel off easy enough with a strap wrench, gently pryed the lens out, then the reflector, but suspecting the remaining housing going down to the pill is removable, threaded? Is that the tough nut to crack? I just can't see any threaded connection there - it would be very difficult working on the emitter from that high up. Anyone who's been there, done that, can provide any input?

Also, I was really expecting to find an extra wire, at least, for the mode selection inpout to the driver, and I don't see anything. Anyone knows how the mode selection works as inputs to the driver?It must be obvious, I'm just not seeing it...

Any updates on your experiments, _the_?

Tom, I haven’t been able to remove the head down to the pill as well, but my soldering iron is long enough to reach in to desolder/solder the MCPCB connections.

The mode changes are triggered magnetically via the rotating mode selecting ring. You’ll see some small chips around half the outer circumference of the driver, those are the magnetic sensors.

Ahhh, mystery solved bout the mode switching - of course, duh on me...

Ok - cracked her all open now - got the tailcap off with a strap wrench - it was heavily glued, appears. Got the head off the pill section - it was threaded with blue LockTite, so it appears, so can get a lot closer to the LED now. I used 2 strap wrenches as _the_ did - didn't need heat, just slow pressure til she started to slip, then it was very stiff getting small movements, then she loosened. The loosening seemed identical to when I opend a 7G9, only this time I didn't scratch the hell out of the housing , you learn...

_the_ -- did you try the XP-G2 yet? I'm thinking of the resistor mod too, here: https://budgetlightforum.com/t/-/16603...

the best way to open the head of the TN31 is by puting it in boiling hot water for around 2 minutes inside a ziplock bag, then use strap wrenches, not much force needed.

Thought I'd give it a try with the wrenches first, and it was do-able. I posted this on your mod thread, but that thread is not too active:

Alex - on your resistor mod to the TN31, did you piggyback your 0.12R resistor on one of those 2 shown in the pic in the other thread? Or just cut it in with wire, laying it along side somewhere. Spasmod is saying there's not enough height space to piggyback. Also, have you taken any light meter readings of results?

Tasteless cretin! :Sp