My first dedoming - failed

Still new here and I have been reading alot of about dedoming so I tried it yesterday on my XM-L T6. First I tried the razor blade method but it wasn’t a clean cut. I had a couple of lines on the dome. So I decided to try the gasoline method. The small piece of the dome came of easily after 1/2 hour but noticed there was still a small piece left on the emitter. Not knowing that it was because of the 3 ultra small hair wires and accidentally broke 2 out of the 3 wires…failed.

In the future, what is the best way to remove the dome material at the wire location?

Thanks for your advise.

I’ve done exactly the same thing. Maybe if you left it in there longer the rest of it would have come off too. Gotta be uber-careful around those hair-like wires. :wink:

Gas needs a least 2 hours - when bubbles start appearing under the dome, then it flicks off easy. I use a toothpick to clean up around the phosphor but never on the phosphor - I've never seen material left on the phosphor itself. I use a 20x glass with a light built in. If there's stuff in between the wires, it stays there! I'll give it a few good squirts of isop. alcohol to clean it up.

I'm 100% with gas - failed miserably on other methods first.

Gas method thread here:

As tallboybass was saying, if you had left it in the gasoline longer, the remnants would’ve probably come off. Either that, or you they would softened enough that you could just use a toothpick to push them off.

What I’ve done (for dedoming a new emitter) is to (1) puncture some holes in the dome using something sharp, like the end of a pair of tweezers, then soak it in gasoline for several hours or maybe even overnight. I then wash it under running water.

Can't get any better than this:

2 - 2.5 hours, wait for the bubbles to appear... This is in an HD2010 that gets 212 kcd

Please don't do that, or advise others to do that, either. Razor blade, x-acto, box cutter, sharp pocket knife. There's no excuse for not having single edge razor blades, you can get them in small packs even at grocery stores, or a box of 100 at any auto parts or home improvement store.

Lightly drag the blade across the silicone, just light enough to score it and break the very outer skin. Poking at the dome with anything can shift the dome enough to break the bond wires, as they are embedded solidly in the silicone and if the silicone moves, the bond wires do too.

I red on other posts that the led should stay around 24 hours on gasoline, now you say that 2~2.5h works... Is it bad if the LED stays on gasoline more than 3 hours?

I need to de-dome two leds, I did the razor method but never the gasoline method, so I also would like to be sure on how to do it.


Very clean de-doming! How much current is that XM-L2 receiving in your HD2010?

Do you think a dedomed XP-G2 would give more LUX?


Ok, I won’t advise anyone, but I’ve done a number of emitters, including XP-G2s, XM-Ls and MT-G2s, so this is what I do, and you can see pics of them in various posts/threads. No problems with the wires so far.

FX-32 - it's an XM-L2 U2 1A. 12 hours or 24 hours is fine, but if you are in a rush, the last several I've done I've seen them get bubbles in the domes after 2 to 2 1/2 hrs, and that's when I take them out now. Dunno what you read, but I know my gas method has evolved, but not one failure yet and I've done dozens, including 2 BTU Shockers, 3 each. I've done up to 24 hrs - no side effects I've seen. Others I heard go days. I think it's better the shorter the time is, but, who knows...

The HD2010 has 6 added 350 7135's, so 4.9A - best reading I've gotten was 4.72A - awesome #'s. Here's the driver:

Thanks for the answer, a few seconds before you post I noted that it was an XM-L2 and edited the post, sorry.

I'm going to try then, maybe this weeks the LEDs will arrive, I have some spare petrol ready for them :D

I stuck a fork in a light socket and didn't get electrocuted, I think I will keep doing it, nothing bad has happened so far.

Good for you, comfy :)!

Yeah, seems like the days of slicing off the dome is getting old.

I’d certainly Tom E’s (patented) gasoline method or if you don’t have time, Vinh’s (trademarked) heating the emitter then lifting the dome off. :slight_smile:

try a fork in one socket, and a knife in the other. report back your learnings

Thanks guys, when removing the XM-L T6 emitter; it was held with a grey glue. I will placed an order for a new emitter and driver.

What should I use to glue back the emitter?
Should I replace it with a XM-L2-U2 or U3?