Regarding break cleaner… be aware in the US there are green and red cans. The green, if I remember correctly, is non-chlorinated and the red is chlorinated. The red is the one that you need to worry about around plastics, but it is a much better solvent. I use both on firearms and only green on lights and electronics. I have see the red make plastic gummy and change colors.
Bottom line is that if the spray yer using doesn’t say, “Safe for Plastics”, yer gambling. High quality electronic contact sprays will typically say that. And I don’t care watt anybody sez, electronic contact sprays tend to evaporate faster and leave no residues. Evaporating faster means ya also have less of a chance shorting something out cuz ya got impatient to fire things up.
I’d have to be pretty dam hard up to use brake cleaner on an emitter or PCB that’ s fer sure. :laughing:
Have contact spray From CRC but don’t evaporate.Maybe not right for dedoming
I use it on switchs and contact points to avoid oxidation and increase cross current,it work well.
For this Led I’ll try again petroleum for lighters.
For dedome SSt-20 what about Acetone? Should be more aggressive,so maybe less time to wait.
It evaporates. Maybe not the absolute fastest butt it evaporates plenty fast enuff.
The fastest evaporative contact cleaner I almost exclusively use is, Puretronics Contact Cleaner. Stock No. 3500. Relatively cheap yet absolutely fantastic stuff. :+1: :+1: :+1: :+1: :+1: :student:
One other tip: Take a can of compressed air, hold the can only horizontally, and after ya spray the contact cleaner over your partially dedomed led, give it a blast or two of air.
This will clear out tiny particles of dome material from the phosphor and any remaining contact spray will get blown out too. :+1: :student:
My CRC it’s another old product called “electro”.Not a specific contact cleaner as you said and guarented doesn’t evaporate,infact he still where I had applied
But I”ll try also your method
Finally I can use my chemistry degree. The base of an LED should be ceramic. The dome should be clear epoxy or clear epoxy with bismaleimide-based polymers added for strength and heat resistance. The Phosphorus is probably vapor deposited with Silicon “the element, not the gooey stuff” I’d say some of the harshest solvents out there should be fine. Of course I’ve been out of a lab for 27+ years.
Some datasheets mention the materials used, Nichia’s for example and the dome is made of silicone, Cree presentation about dome and domeless LEDs mentions it too.
Then have at it, the silicone should easily be removed with harsh chemicals without harming the substrata. Less harsh try Vinegar and isopropyl alcohol with good long soaks.
Inspired by this discussion about chemicals and dedoming I did few tests. I put WD40 and brakecleaner in small container. Those small plastic cases that Simon uses when he sends emitters.
I put sliced Xhp70.2’s in both of them. WD40 hardly did anything in 24 hours but brake cleaner did this in 10 hours:
Seems promising. Let’s keep experimenting. (Grey stuff is just leftover thermal paste)