Just fyi, added to OP:
Please find MEM's detailed post on gas dedome method here in post #131 here: https://budgetlightforum.com/t/-/32252
For those who don’t click the link, MEM has tried many methods and has settled on gasoline, with beautiful results.
I started using gasoline, with very mixed results (some perfect dedomes, many dead leds). Eventually I switched to the method of running the led at 2amps for ~30sec then “flipping” the dome off while the phospors are still hot. I have never killed an led this way, but the results weren’t always pretty.
After MEM’s findings, I decided to try gasoline tonight, and I too achieved perfect results. This experience along with my previous experience has led me to a couple conclusions.
1. The gasoline matters. I have less success with gasoline that contained ethanol or wasn’t fresh (I had a supply sitting in a bottle for a couple months) This time I used fresh 91-octane and it worked perfectly.
2. If it hasn’t worked in 4-5 hours, it probably isn’t going to work. I remember letting my emitters sit in gas for 20+ hrs to no effect. This time the emitters were basically done after 3hrs, but I left them in for an extra hour just to be sure. You could see the domes were visibly swollen after just an hour.
Ok, so I went from gasoline to hot dedoming and you went the opposite due to ‘results weren’t always pretty’. Are you talking about tint? I thought the greenish was caused by gas, so I’m curious as to what you meant by this. Only greenish issues I’ve had were from XML’s and that was sort of a luck of the draw there. I have 2 dedomed XML’s that I am happy with and all the others I switched to XPL HIs.
I started with gas, then switched to “hot”, now I’ll probably use both from time to time. If I have the time and ambition to go buy fresh gas, I’ll probably do that. I mean messy on the emitter itself as in leftover residue and dome pieces left around the bond wires, etc. I personally haven’t noticed a difference in tint shift of hot vs gas dedomes. It seems to me it all depends on what tint you start with. “B” and “C” tints usually end up ugly, “A” and “D” tints usually end up better. The best Cree tint I’ve ever seen was a gas-dedomed XP-L 2A (one of my first dedomes). The XM-L2’s I pictured are also 2A, for my SP03
Just did my second successful dedome with gasoline and made a timelapse of it. You can really see the dome swelling.
Cool!
I do not use gas now, but I know how to use gas and demonstrated it. The gas must not ever move into air with the LED. An article was written in 1997 or so on the problems with sitting gasoline. It’s not the solvent that harms the LED, it is water. Gasoline mixtures are mildly hygroscopic, and will attract water molecules until dilution occurs. At this point, you would thus be dedoming an LED in a water mixture. Water doesn’t release oxygen bonds too easily, normally, but add molecules which can be oxidized readily like a metal…ah let me get to the point.
Water will oxidize materials used in LEDs. This is bad. Do not allow water to oxidize parts of your LED.
Wow! These are looking so freakin clean, MEM! As if there never was a dome.
Could you please elaborate how to dedome Nichia LEDs? I’ve read somewhere that you’re doing a two step process with two different solvents…
Hhmm, not sure what you mean my move into air with the LED… ?? Not sure what all this means in practice?? What exactly are we supposed to do?
I think it was just a couple months ago you were using gas, what is it now?
Trade secret?
I’ve had excellent results with Industrial strength Goof Off. Its fast and complete. The dome basically melts and falls off the emitter. Leaving only some goop under and around the bond wires.
This is awesome thread 
MEM’s new method looks very good.
I recently had very bad results with gas and all that happened in cold environment(0 celsius) so in colder environment you will need much more time with gas dedoming method.
If you can try dedoming in warm environment like 25+ celsius(in the room near wood stove) and you’ll see much better output on your led from gas dedoming method.
This thread needs to be alive…
If there is new, faster, or better method or any new experiment it should be posted here.
I also wonder how Olight does it?
A wood stove is the type of heat source I’d keep gas away from. Even small amounts. How about just putting the container in warm water instead. Less chance of an insurance claim.
Good idea Although warm water will be cold after more than 20 minutes.
Gasoline (Petrol) auto ignition temperature at 247–280 °C
So i think I will stick to stove after all(closed glass jar used). Near stove it has constant 28 °C.
Not in a crock pot. :bigsmile:
Also notice the lid is flipped so it doesn’t build up pressure. Plug it in anywhere it isn’t raining and you can heat to your hearts content without blowing anything/anyone up.
Please play safely kids…
I don’t have electric pot. Can it be set to lets say 30 C? If it can maybe I’ll consider to buy one.
Depends on what you can find. Some are 1 mode, some 2-3 mode, and some are digital control with programmable temperature. The one in my picture is a “dip warmer” and specifically states it will not cook meats to a safe temperature, so I think it runs around 115-130°F (45-55°C). I picked it up for about $5 on sale.
I’m just trying to give people some alternative ideas for heating up their combustible liquids that doesn’t pose a fire risk. If you don’t want to buy something, boil water and use a cloth wrapped ceramic or glass container, then add a little boiling water every 20 minutes or so to keep the temperature up till the dedome is done.
All that said, I hot dedome 90% of the time, and when I do need a 100% perfect dedome I don’t use gas or heat anyway.
Could you share what you use?
After all… This thread is about that 
It’s not my secret to share unfortunately. I promised to keep it to myself and I stick to my word. I believe I am OK hinting that it’s a solvent and no one here has mentioned it that I have seen, that’s about it. Sorry, I hate being mysterious as much as you probably hate me not being able to say.
Has anyone tried B-100 or kerosene?