I use MEK works very quickly, less than an hour.
I remember using this stuff like this years ago when I was doing auto detailing. The can said it would remove silicone. I wonder if this will dedome a LED?
3M 08984 General Purpose Adhesive Cleaner - 1 Quart
3M 38984 Specialty Adhesive Remover - 1 Quart
+1 for MEK.
+1 for MEK....w/MSDS
This stuff is naaaasty.
I checked out MEK, turns out it is illegal in Sweden 
+ i dedomed an XP-L V6 1A with thinner today, first i sliced of the dome, and the i put it in thinner for an 1 hour. Very clean & very fast, and no residual stank from gas.
I wonder if you warm the solution slightly if it works better. I used thinner once and the dome did not come off, even after two days. It was my first dedome. I did suspend it upside down fully submerged. I finally took it out and slowly began lifting it off. Lift a little, set it down, again and again until I was convinced that the wires would not be disturbed. Then I got it off after about 5 minutes. Seemed like a serious PITA.
Honestly, I do not like running them exposed. So, my method now is to slice it down as far as I'm comfortable, polish it up and be done with it. That way I do not have to worry about using costly LED seal.
If you use a very sharp & new unused razor blade (like feathers platinum for example) you shouldn’t need to polish it, after you slice it, when i use that the cut looks clear, almost clearer than the stock bumpy shaped round dome.
The thinner i used was cellulose based, and that i sliced off most of the dome before i even put it in thinner also speed up the process a lot.
Its a lot less hazardous than RUG (regular unleaded gasoline) and a far more effective solvent in every situation that we’ve ever used it in (aircraft/aerospace/automotive/marine). As with any solvent/desolate, a small measure of common sense can virtually eliminate exposure. Id be far more worried about the long term exposure of eating greasy fast food than breathing trace amounts of MEK in a well ventilated area.
Some people seem to have successes with thinner. Are there different types of thinner or just one type?
I really don’t know, but the type i used specifies that is is cellulose based, i guess that means some other types exist.
I have been really pleased with dedoming with thinner, i absolutely hate the gas stinkness the led+star gets when i have used gas before.
After the dedome in thinner, i wash it by placing it in a jar of 80% strength foodgrade ethanol, it is basically crazy strong vodka J), to get it clean from any thinner residue.
No smell on the star or led, good tint, clean & fast dedome 
The only thing i wonder is how long i can leave it & if it will get damaged if i accidentally forget it in thinner, i know Mitko said that when he left led’s for to long in acetone they got damaged, and i wonder if thinner could do the same.
Use common sense with any kind of Flammable solvent. Always use in a well ventilated area, Gasoline is fairly nasty also, as it contains benzene. I started using MEK to solvent weld Plexiglas, and it works very well. I haven’t tried it but I can imagine lacquer thinner would work fairly well for de-doming. My major issue with gasoline is the smell, as it is persistent.
I tried the heat method last night on one of my FF 102's. I warmed it up with my reflow gun until it got hot enough to pull the led off the sinkpad which was also soldered to the brass pill. Let it cool for 5-8 seconds the started lightly lifting the edge farthest from the bond wires. Then suddenly a chunk came off at a slight angle from the bottom at the phospor to just above the bond wires. Not what I was hoping for. Had to slightly trim down the high spot above the bond wires. I'll use gas or some other chemical next time or stay with the slicing method.
What is the point of dedoming? More light?
More throw. More powerful and longer reaching hotspot.
Alright so I’m trying my first dedome today after reading all of your guys’ comments. I decided to try the paint thinner method as I’ve heard that it takes a lot less time compared to waiting overnight. Some say as little as 2 hours for the dome to fall off. Well, I rigged up a hanging system for it and let it sit for 2 hours; no changes. 3 hours; no changes. I decided to see how “gooey” the dome felt, so I used my fingernail to scrape the top, and managed to get a little bit off, but not all that easily (I figured it would feel like soft butter but it still had a jelly consistency). I bought the paint thinner today from Home Depot, so I know its pretty fresh… should I let it sit overnight or am I doing something wrong?
Here is my setup
Not all paint thinners are created equal apparently. I left mine in for 2 days and nothing happened. I think we need to find out what the right type of thinner is to get.
I always slice of the dome with a new very sharp razor blade, about half off before i place it in thinner & most of the dome is usually off by 1 hour.
Does yours say cellulose based thinner on the can somewhere, because that is what i use & so far the only successfully quick dedomes i have read about here, using thinner have been of the cellulose based version, there are several, and not all work for dedoming leds.
Mine is mineral based, and can not find “cellulose” anywhere on the can. Here is what I purchased: 1-pt. Paint Thinner I guess I need to find one with cellulose…
Ok that explains it.
I read up on this cellulose thinners just now, it is NOT based on like i said, but a solvent that can dissolve cellulose.
I have tried finding this kind of thinner in the US for you, and it looks to not really be sold anywhere :~ I don’t think you guys use it at all.
In the UK & Europe you can find it anywhere & in Sweden of course it is readily available, but in US it doesn’t seem to be sold, strange.
If i where you i would just use some Gas, it works just fine it takes a bit longer & it is a bit harder to get rid of the residual gas smell afterwards.
I’ve been reading up on it as well. Short of getting a degree in chemistry, it is pretty difficult to find something exactly the same as what you have. I’ve been trying to read the Material Safety Data Sheet to figure out if Lacquer Thinner or Acetone are similar, but I’m no scientist.
I’d much rather find the correct solvent that would dedome my led within a timely manner, but I may have to do the gas method after all.
Anyone want a free can of half used paint thinner? :Sp