How to remove glued pcb including led from pill?

Just got an fandyfire STL-V6 in from lightscastle the other day. I’ve just desoldered the driver from the pill and I’ve tried to remove the pcb from the pill. It seems to be glued in and I just can’t seem to get it off. The pcb fits in the pill, so there are not many possibilities to get under the pcb.

Anyone got any tips for me to get it off?

I generally take a pair of needle nose pliers and twist until the bond breaks. You want to twist, not pry.

If it is actually glue, I usually use a torch from the underside and heat it up. Not red hot, but heat and try it, heat and try it, etc.

Put the pill in the freezer until it gets really frozen; the metal and the glue will contract at different rates, so the glue may crack a bit and lose strenght, and with the aid of a screwdriver tip lever on the PCB…
Don’t know if that sounds stupid, maybe it helps. :slight_smile:

Cheers

Use a chisel if you can get it in next to the star just give it a hard twist. If you go to the trouble of removing it you might as well put it on copper while you are at it so don’t worry about damaging the star just don’t ding up the aluminum.

I’ve used the technique that RMM mentioned several times, and it usually works.

Basically, you put the star into a vise to hold it, then you take a needle nose pliers and put each of the tips of the pliers into one of the notches in the star/pcb. Then simultaneously (carefully) squeeze the pliers to maintain pressure and also continue to push the pliers “down” so that the tips stay in the notches and turn/twist the pliers.

Be careful while doing this, because if the tips pop out of the notches, you might smash or damage the emitter.

Thanks for the tips! This is the situation:

There is no room to put a chisel or something next to it without wrecking the pill. I tried the freezing trick, that didn’t work. The twistinh also didn’t work, it isn’t possible to put enough force on the star. :~

Next the torch trick, first need to order a torch….

Ow yeah, the star and led need to go because I’m putting in a XML2 on noctigon. 8)

Had the same problem a couple of days ago. I used a small flat blade screwdriver. I forced the tip under the pc board in the cutout area where the LED power wires feed through. I had to wiggle it back and forth and rock it up and down until the tip finally started to wedge under the PC board and then the board popped right off.
It will scratch up the pill surface, but that’s easy to fix.
You will have to use a good quality screwdriver. Those cheesy Chinese mini screwdrivers drivers are too soft and will bend. I used an old Xcelite screwdriver- it’s tough.
I was not worried about deforming the PC board or damaging the LED since I’m replacing both, but I lucked out and had very little damage to the aluminum PC board.

You could try the thermal shock method. Not sure it will work, but worth a try.

Prepare 2 pots of water… one filled with ice water with ice cubes, the other filled with boiling water. Drop the pill in one pot, wait 15 seconds, then use long-nosed pliers to pick up the pill and immediately drop it in the other pot. Wait 15 seconds and repeat. Hopefully the rapid temperature changes will cause the glue to break.

Regarding the twist method: You may get better results if you do the following:

  1. Use a rubber-jawed vice to hold the pill. If you don’t have one, you can make a temporary one pretty easily: Put some rubber indoor stairway grip tape on the jaws of your vise and use that to hold the pill. Note: Do not use outdoor stairway grip tip as that has glass and rough particles in it. The indoor stuff is solid rubber and won’t scratch the pill.

2. Desolder the LED leads and remove the driver first. You can’t perform the twist method with the leadwires in place as the wires are blocking the slots you need to insert the long-nosed pliers.

3. If you need more leverage, consider using an adjustable wrench as a lever to help you rotate the pliers.

The driver and the led leads are allready desoldered. I don’t mind to damage the star, since it is going to be replaced. But the pill needs to live to see another day.

Going to try the thermal shock trick first. Lets see if that works.

You can put the entire pill on a pan on the stove. I have done that before.

What I do: remove wires, remove driver (obvious I guess?). Usually you can use something strong/pointy, like a solder pick tool to catch an edge of the star from underneath, thru one of the wire holes. Try a couple of hammer blows on the pick. Doesn't matter if you mess up the 25 cent alum star, at least for me... If cant' get an edge to hammer on, I usually do the pry method - never really damaged a pill top, if scratched, sand out - but I'll sand the pill top anyway from 100 or so to 2500 GRIT before mounting copper.

I’ve managed to remove all my emitters using the freezing technique. You need to use a screw driver to force the emitter out, and the trick is consistent pressure and patience. You’ll hear slight creaking or cracking as you apply pressure, it may not seem like you’re making progress however if you keep the pressure consistent and try from different angles on occasion it will eventually give. Make sure it is well and truly frozen, I usually leave it in the freezer overnight.

WKJR, that’s a little dejavu : HERE

Thanks Orion, I was considering posting that link and you’ve done it for me. I mentioned I got all my emitters off, but not all in one piece LOL!. Truth be told since the first one, I kind of figured out the freeze technique and have used it to great sucess ever since, easy once you know how. :wink: . Of course I owe that knowledge to E.

My light had the same pill; I stripped it down and then used a butane torch to heat the pill. That loosened the silicone-type thermal adhesive and allowed me to remove the star using a combination of the other techniques listed here...

- Picked the pill out of the freezer yesterday, put constant presure on it……didn’t work. :frowning:

- Next gave it some thermal shock therapy……didn’t work. :_(

  • Got out my fake dremel and a mill bit. Made the hole at on of the lead holes larger and tried to get a bigger screwdriver under it……didn’t work! |(
    This is a pill/star combination out of hell! I have to say my patience does run a bit short, but still……

Just ordered a torch from dx, when it arrives I’ll try that method. It will come off! (It has to, the noctigon is allready in transit…)

If you saw orions link to my first attempt it isn’t particularly easy if you haven’t done it before, I ended up dremelling right down on the emitter and after a few minutes I was surprised at how easy it came off in the end. Of course that meant I completely destroyed my first emitter.

WKJR, no worries! If that dun work, rem there’s still the BGA IC adhesive remover to try : HERE

I’ve had such difficulties in removing some of my lights, and the Courui big head throw is one of those. I used a lighter to heat it from the bottom trying to make the bond softer, but the solder melted first and the stock LED came off! That’s actually not my intention to desolder the LED but the high temperature did it, it was good still, which I don’t need to worry about destroying the stock LED and now I could use as much brute force as I wanted. |(

A lot of prying and re-heating were involved and finally the stubborn star came off. But it was really tough for me, still looking for a more efficient way to remove this kind of tough stuff.