I found here on a dutch forum that an electronics guy used petroleum-ether to remove silicone remains. I have some here where I work, I will give it a try. The composition is not far from gasoline, but it is much cleaner. It is even more equivalent to Coleman Fuel (which is also much cleaner than gasoline).
I doubt that it will work. It is a pretty mild solvent. Good on sticky residue from tape and tends not to harm most plastics. I use it for polishing plastics and LED display windows with red jewelers rouge.
The petroleum-ether I have here says: 100-140Ā°C. I may have some Coleman Fuel as well somewhere. Perhaps when I can find some time and enough spare leds I will do a 'great dedome test string' one of these days..
I never had any luck with the XRE twist, always some bad residue left behind. And removing those always a mess. My success rate is only 33%, 1/3 - one ruined wire, one bluey, and one not-so-good-but-I-leave-it-alone-anyway-otherwise-rate-would-be-0/3ā¦ heheh.
With petrol soak, the whole ring and dome just slid off. I have 100%, 1/1 success on this method for XRE. Best, cleanest result out of the four too.
LOL, Iāve got a zoomie with that problem already from a thick hold down ring - the ring reflection is outside of the beam, but still wanting to paint it black.
No, Iāve got a spare XRE and if I de-dome the ring will go even if that ruins the emitter.
I have used the heat method with near 100% success. Fairly sure given 100 XML or XM-L2s I could do every single one of them without failure now that I have the technique down.
I have done approx. 2 dozen XMLs (+ two more this morning), an XP-G2 and a XP-E.
I find it easiest to do if the LED is already mounted on a MCPCB in a torch. From there I remove any screws or glue etc and lift the board so the board is āfloatingā in the air with the leads still attached. I then run the torch on high until the board is too hot to hold.
Placing my figure as far down the dome on the opposite side of the bond wires I peel towards the wires slowly: you will notice if the heat is not right the dome is harder to peel off. If doing this for the first time have a play with peeling the dome at different temperatures and try get a feel for how hot it has to be. You can reheat the LED at any time during this process.
The result is almost exactly 110% increase in lux for reflector lights.