There actually are some splatter/ spot marks of some kind on there in the ‘bullseye’ position of the pcb. The electronics cleaner is fine but rubbing alcohol on a cotton swab + elbow grease is better. Clean both the underside of the popper in a twisting or ‘lapping’ motion with the swabs and ensure before reassembly that there arent any cotton fibers hanging around under there.
After I clean it with alcohol, should I apply a film of anything? Or just leave it completely bare?
Clean and dry.
Cleaned it with 99.9% and replaced the o-ring with the 008 size. Light is happy and so am I.
A big THANK YOU to all!
And the problem is back. Unless I press dead-center with just the right pressure, it won’t toggle.
I just want to order a replacement PCB at this point to try that. Can anyone help me find out where to buy one?
Do you have a soldering iron?
Yes, and I’m OK with it. Not a master, but I’ve done several hundred small connections.
What should I do with the soldering iron?
I think the aswer might be in post #9 and #18
I hope you figure something out
These switches are very simple. They consist of a flat plastic pcb, a flexible springy metal “popper” and a strip of Kapton tape holding it all together. When the button is depressed it pushes down the popper which inverts (giving the click sound), while creating an electrical connnection between its corners and center.
The connection might be failing to trigger due to the flexible metal “popper” not properly connecting at the center and edges when the button is depressed. This could be because when the popper clicks and inverts it isn’t quite touching at the center.
The following might be worth attempting:
- The popper is held on top of the pcb with Kapton tape. Peel off the popper and completely remove it from the pcb.
- Put a tiny dab of solder paste in the center of the pcb where the popper touches when the switch is depressed.
- Apply soldering iron to it. The goal is to add a tiny bumb directly where the popper hits. This should cause the switch to reach connection without having to depress quite as much. I would aim small. A dab the thickness of a piece of paper might be all that is needed.
- stick the popper back in place, reassemble and test.
- If the switch action is too soft or fails to click, it is quite possible the dab you just added is too tall. Remove the popper and file it down with a small handfile, or use a solder removal tool and reapply the solder.
- I expect this may take multiple attempts of fine-tuning to get it just right. You might need fresh kapton tape to hold the popper in position if you try this too many times as the glue on the stock tape might wear out.
Some additional notes:
- I recommend avoiding tampering with the popper unless you’ve given up all hope of anything else working. If you damage or destroy the popper, it might not be reparable. For these reasons I suggest against trying the following except as a last resort:
- If the problem is connection between the corners of the popper and the pcb, one possible solution is to solder one corner in place while leaving the others floating. The downside is any heat applied to the popper might destroy its springiness and destroy the switch. A better option is probably to completely remove the popper and clean all corners with deoxit.
- Another option that might improve springiness is to bend one or all of the corners slightly down. In theory this might mean more tension is required to actuate the switch. But again, the risk of permanently destroying the popper is high.
Sorry for leaving that hanging. Fireflight nailed it. Exactly as I was going to recommend. Cleaning the popper and pcb again with alcohol AND deoxit d100 or gold would be first for me. Cleaning the first time seemed to help, maybe some flux was missed on the bottom side of the popper. Simplest things first.
Otherwise, the super short solder bubble/dome on the center pad is what I believe should cure this.
We’ll be here for any other questions. Good luck!
Put the nubin back in and very gently press the switch in various directions 50+ times and see if you can duplicate the failure.
Thanks for all of the above.
Is this the right product for cleaning?
https://www.amazon.com/Hosa-D100S-2-DeoxIT-Contact-Cleaner/dp/B0014F110I
Yes, but I personally prefer the needle bottle https://www.amazon.com/CAIG-LABORATORIES-D100L-25C-Contact-Cleaner/dp/B0000YH6F8
Also, this is a nice bundle https://www.amazon.com/DeoxIT-G100L-D100L-solution-applicator/dp/B01BW8VRVY
I am not a fan of 1ml containers. It’s irrational, I know, but I just don’t like paying money for something that small haha.
How about one of each of these:
- https://www.amazon.com/DeoxIT-Gold-Brush-Contact-Conditioner/dp/B0015A7CYG - “DeoxIT Gold G100L-2DB Brush Applicator, Contact Cleaner/Enhancer/Protector for Gold Surfaces, 7.4 mL, Pack of 1”
- https://www.amazon.com/gp/product/B0000YH6F8 - “DeoxIT D100L-25C Precision Needle Applicator, More Than A Contact Cleaner, 25 mL, Pack of 1”
And do I apply the D100L-25C for cleaning first and then the G100L-2DB after?
Gold is for just that, gold. So its great for pcbs and gold plated springs. 1mL will last you maybe your life. I use my d100 weekly and had it for 2+ years, still 75% left. D100 is great for everything else - brass, Al, battery contacts etc.
Is there gold on the FW3A that I need to clean?
The gold colored pads on the PCB are in fact gold, so that’s the primary application for that stuff. I regularly tear down my lights and clean the ground rings of drivers and tail boards with it. Keeps flickering away and current maximized. Most times I get a light that’s acting up from someone all I do to fix them is clean the gunk, deoxit all conductive interfaces, and lube the o-rings. Voila 95% of the time.
Thank you. Very helpful info. This is going to be useful for years to come.
Is the cleaning technique for both of these liquids. basically “wipe it with a lint-free cloth”? Anything special?
I’m tired. Thought this was about putting actual gold in the flashlight for a minute. 1mL of gold for each flashlight. Then I started wondering why there was only 75% left & what performance advantages it was bringing to the flashlight. Higher CRI, better tint, more lumens?