Home Hardware also sells a lacquer thinner made up of toluene, methyl alcohol and methyl ethyl ketone, that seems like a pretty nasty combination.
Mem talked about his method of dedoming being a two step process, attack the glue first then swell the dome off. I can’t figure out if he was using different chemicals or wetting the base of the led for a while and then submerging it.
@Tom I also couldn’t find Nitro thinner. I read somewhere that MEK worked, so I started using it. The SST-40 dedomes nicely with it. The couple of XML2 U4-1A’s I did in it had the usual tint shift.
Readily available at HD. I have only tried it hot, so not sure how well it works cold.
The answer may have been under my nose this whole time (some pun intended there). I’ve been using a solvent called Wil-Bond made by imperial. I don’t recall ever trying to do a full chemical dedome with it for fear of phosphor damage and generally I’m impatient. BUT - I have used it with much success to clean up the bits left behind during my hot dedomes and it seems to make quick work of the silicone scraps. So I looked up the MSDS and compared it to the solvent list I’d linked previously… What I found is that it’s full of theoretically effective solvents. I will say it’s odor is definitely nothing to be taken lightly. Even the can sealed up and in a cupboard, I can smell it on hot days when I walk into my hobby room. The good news is it can be found in the US at Walmart and has free shipping for ~$18
I’ll throw a few sacrificial LEDs in there tonight sometime and see what happens. I don’t think I’ll try heating it at all. Don’t have the appropriate space or heating equipment for that right now.
Update on previous post:
(only relevant to Dutch dedomers)
It’s a little confusing…
This “ELMA thinner” is sold as ‘thinner-tolueen’ but it doesn’t say ‘tolueen’ anywhere on the bottle, not even in the ‘samenstelling’ (contents).
However, after asking ELMA themselves they assured me there is tolueen in it.
They promised to send me a more detailed list of ingredients.
I will report back on this here.
Been testing White Spirit on an old XM-L and newer XM-L2s, a little bath and 3 to 4 days to soften and remove leftovers; does a pretty good job. If in a hurry, bain-marie.
Tried one more time and this time without heating the Toluene. It took a long time to get the dome completely clean. But it was totally worth it! For the first time there was not a single hint of green in the tint!
I will post a beamshot later showing this sst-40 against the one done in Nitro thinner.
Sledgestone, in order for camera pictures be worth comparing chromaticity wise, a common reference point must be used (usually “daylight” or 6500K). If “auto” is used the device will try to detect and compensate the spectra for it to look like daylight, usually with bad results with some sources but good with others (hardware and software dependent too, of course).
The pics look good to me, at least with regards to differentiating the dedoming process turn outs.
I used to soak my LED’s in “wasbenzine”, what translates into: white-spirit; refined petrol; cleaning spirit; cleaning fluid; dry-cleaning naphta. Confused? Not really, the chemical compounds involved are seldom identical from brand to brand. Last time it took 48 hours, and I still managed to tear off the bond wires when removing the residue.
So I ordered some MEK (methyl ethyl keton) and the dome of the SST-40 came off in 2 hours, and much cleaner.
