A Perfect Dedome?

For SST-40 I am giving up on liquid method and switching to shawing, just have to buy some razor blades.

Well the liquid de-doming isn’t the problem, that I’m finding out with the tougher LED’s, it’s the time, nothing good comes fast I guess. :smiley:

And too Hot seems to just explode the domes up off these tough LED’s and takes phosphor with it, as I witnessed doing the Hot and I mean bubbling HOT de-doming (MEK :confounded: ) the XHP LED’s. :cry:

I’m going to reflow 3 more SST’s and hang them and just go slow, till they fall off? Then see what’s UP? :person_facepalming:

Normally I just use one of them Jewelry Sonic cleaner’s and IMRON paint thinner but it could take a week or two, because I only run it when I’m going to be around to monitor it, other wise it just sits in the fluid.

Let’s call it heated chemicals method, works fine for me when I dedome XML2, XPL or XPE2 leds, usually I hang then upside down submerged in liquid heated to about 45-50 degrees celsius. It takes about 40-60 minutes and as soon as I notice that the dome has lifted from the phosphorus surface I take them out, remove the dome, wash the led with 96% alcohol then remove remaining silicone around the phosphorus “core”, wash again with alcohol then with destilled water, dry it out with compressed air and that is it, for XPL its even faster because silicone dome doesnt go around the led like on XML2 or XPG2… leds.
This method gives me minimum tint shift, I would say that 6500K only drops to 6000-5800K (but I have no way to measure this so, it’s my subjective opinion).

Where can i buy sst-40 hi ?
Thanks

for better beam focus, better throw.

I am sory, that’s confidential, you have to have at least 1000 posts for that info. :smiley:

You really need to read this forum a lot more before commenting…

I did the click. Each of you got one.

Thanks, that’s what I get for trying to explain things :person_facepalming:

I see no rudeness but then we are all different. :+1:

OK, I’ll try to explain why do I see 2 comments as rude:
1.

My reading of this post is “your posts are illogical”
2.

I don’t see any explanation in here. Just silencing a new member who asks questions.

BTW the post when I admitted marking the posts as rude is considered rude by someone.

That’s what I’m thinking right now! :person_facepalming:

I really want to put one in my M25C2 Turbo, I have a de-domed XPL-W2 6500k in it now and at 6.27 amps it’s throwing just over 580kcd conservatively, on a VTC5A. I want to see what the SST-40 can do. I’ll probably change the FET out on the real old Mtn FETDD driver after I take a current reading if the driver can’t supply 8amps to the LED? I have SIR800’s 404DP’s and Infineon FET’s I could try out?

JUST Something to do…. :wink:

Always with the negative waves, Moriarty. Always with the negative waves…

Sort of dedomed an SST-40 on white spirit, but screwed up the little bond wire which connects the two substrate pieces while removing dome leftovers with a toothpick. What is it for?

Cheers ^:)

Hm? Looking at

http://www.luminus.com/images/SST-40-W.png

and zooming in, can’t quite make out any “substrate pieces”.

Is there an antistatic diode off on the side?

I thought it was a reverse polarity protection!

Check comment #8 on this thread where Lexel repaired a broken bond wire.

Link: https://budgetlightforum.com/t/-/47908

That bond wire?

Edit: copy the whole quote so you get the whole picture instead of just saying it’s for ESD protection so you don’t go and put a solder blob there and damage something. (Well maybe works if you ONLY gets solder on the wires but that would be tricky. Maybe wrong… ask the experts)

Aha, much better view. :smiley:

True reverse-polarity protection would have to shunt the full reversed-voltage current as the LED would handle if forward-biased, and that’s way too small. So it’s probably a small zener diode, about o(10V) or so, to just shunt small reverse-biased voltage spikes from static.

Anyone want to test it? :smiley:

Snap together a few 9V batteries, 1 at a time!!, put a 100kΩ resistor in series with it, then “zap” the LED backwards and measure the voltage across the LED. Full battery voltage means the zener ain’t conducting yet. If the voltage is, say, 6.2V from a single 9V battery, it’s a 6.2V zener. If 9V from one 9V battery but 12.6V from a pair at 18V, then it’s a 12.6V zener. Etc.

Keep the current to around 0.1mA (100µA) or less, preferably much less.

Sirius, that has got to be one of the cleanest dedomes I have seen, Good job! :+1:

What did you use to dedome and what steps did you follow?

It’s not that clean as it seems, I was actually not impressed with this results at all, small white-ish dots that you can see on the led surface, that’s actually silicone that I was not able to clean off.
I am using stuff that is not available in US, it is called medical gasoline, super pure gasoline that can be used for cleaning wounds (evaporates fast, doesn’t leave any smell afterwards), It gives perfect results with XML/2 and expecially XPL leds, XPG2 also end up looking nicely, XPE2 leds are a bit stubborn thou.
For example XPL is dedomed in about 15-20 minutes in this stuff at ~50 degrees celsius.
Tried my luck with 2 leds, first one with hot dedome, left it in until I noticed dome swelling (maybe temperature was too high).here are the results, as you can see phosphor layer was also affected, piece fell of with the silicone while I was attempting to clean silicone that was left stuck to the led surface. The second one was cold dedome.

I left the led in for about day or two, I was not expecting good results because stuff I use affects on a tint shift so I usually leave led in just until I notice that dome started lifting from led’s surface, so shortest possible time, after that I rinse it thoroughly with 96% alcohol, blow off with compressed air then rinse it with distilled water one more time -> drying with compressed air and that is it, led i ready to be installed.

When I dedome XPL led I noticed that dome is not swelling its as if the “dedoming liquid” gets between transparent silicone dome and led + white silicone that surrounds leds die and just lifts the dome, results are perfect, as if CREE never put the dome on. Dome on the SST-40 behaves differently.