head lamp shorted out because of WATER how to waterproof!

MarkJohnston

10 kW
Joined
Mar 25, 2021
Messages
619
Hi,

I did a brief search of the forums before posting this but couldn't find an answer. I am not trying to be an 'askhole'. I have a problem and I need help. I am also going to post in a LED light specific forums(I would like to post here too for specific reasons I will address.) I've had two head lamps short out from water or at least I believe that to be the cause NOW. The other was lost due to incompetent manufacturing. My first light was the best, it is pictured below and is now just a circuit board. This light lasted for years and SEEMED TO BE WATERPROOF, but eventually it shorted it, or something. THe second light I just purchased a month ago, and waited a month to arrive from CHINA, and now it's already gone :cautious: in but two days. That light is pictured here too, with how it's mounted and the LED chip WITHIN. I opened up the casing to find a TON Of water inside the other day. IT must've built up because I've been riding around in the rain for a couple days here and THOUGHT I COULD TRUST THE BOX! Apparently not, because it' s not water proof as IS!

DOES ANYBODY KNOW HOW TO WATERPROOF THESE JUNK LIGHTS or ARE THEY NOT WORTH THE TIME? I was thinking DI ELECTRIC GREASE ON THE THREADS and what about some SILCIONE ON THE ENTIRE BOARD MINUS THE LEDS themSELVES!? MUCH LIKE one of those LED STRIPS. REMEMBER I NEED TO STILL FIT THE REFLECTOR/ LENS.

CAn I repair one of these boards using LEDS taken off an LED LIGHT STRIP I HAVE? Maybe the LEDS have themselves have just shorted out? IT MIGHT be the case. I thought the FENDER would protect the light but tons of water is splashing off the front wheel directly into my light.IT's high pressure which is why I wanted to consult this forum, thank you.

'Condensing Waterproofing Highlighting:LOL:' but these lights were good to me, that old board lasted me for years, even with a little bit of water beleive it or not but that particular light is no longer available . covid and chip shortage. OH YEAH I DON'T WANT TO SPEND MORE THAN $20, I am going to retire this bike here in about 6 months and can't spend more than that on a dumb light for it.

Here;s what I bought on new egg. IT was FUN while it lasted! (IM DEPRESSED NOW!)

 

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A friendly tip, It’s common netiquette to avoid writing in all capital letters, it’s equivalent to someone screaming for the reader. If you post in normal writing then you’re far more likely to get answers.

And yes, it can be waterproofed. Depends on the part i try to seal, if it’s possible i’d seal the lamp cover with some silicone since the LEDs create a lot of heat and a good heat exchange is needed.

For electronics I normally use liquid electrical tape, 3-4 coats or until the surface of the coating is without voids. Hot glue also works well for sealing. But: on the led boards both those sealants will get too hot, then a neutral hardening high temperature silicone will probably work if you keep amount to a minimum. Don’t apply anything on cooling flanges.
 
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Sorry the caps were just to high light the important stuff. Most people skim through these. I can't seal the lamp cover because I will need to screw and unscrew it.
 
I need to avoid the board getting wet. Short circuit. Buy I did find a giant puddle inside the lamp

The most accepted method of “waterproofing” for ebike parts is to give water a way to get out of the devices. Unless an electronic part is designed to be waterproof by the manufacturer, it’s very difficult to make it so. Water gets in through the smallest of gaps— it even comes in as water moisture in the air as a part “breathes” when it heats up and cools down. Many waterproofing measures do not fully seal a device. Instead, they allow some small amount of water in and make it harder for that water to get out.

Thus, placing a small hole in the most-downhill part of a device is a decent way to help water not pool in a device.

If you’re committed to spending less than $20 for a “dumb light” (your words) that you’ll use for 6 months, consider a battery-operated option from makers like Cat Eye. Sometimes, you get what you pay for. I personally have gotten MANY hours of excellent use out of the rechargeable bike light I bought from Night Ize for $55 a decade ago.
 
Ok so maybe tons of di electric grease on the LED, plenty of silicone to seal the reflected and drill a teeny tiny hole in the bottom most part?

I should be able to unscrew LED even with silicone on the threads?
 
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Also do you guys see the black octopus thing on the board? It has a huge dab of silicone on it. One does and one doesn't.

Edit: Ok as luck would have it I was somehow able to find out what the thing is called. I beleive it is called an IC chip, here it is pictured on ali baba. IT is ok to put a dab of silicone on that ? seems like it helps a lot in waterproofing this LED SMD board. The one I got from new egg didn't have the IC chip with proper waterproofing. NEed to send it back

 
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Ok so maybe tons of di electric grease on the LED, plenty of silicone to seal the reflected and drill a teeny tiny hole in the bottom most part?

I should be able to unscrew LED even with silicone on the threads?
Dielectric grease is normally used on things like connectors.

LEDs can get hot. Test by touching with your finger. You will only do that once. I would put nothing on a LED. Some LEDs have heat sinks.

Re: "unscrew LED even with silicone on the threads?" Thread sealer is normally used on threads that need to be taken apart. Silicone might act like glue.

Think like water. Seal up outside of light best ya can. Electrical tape? Drill hole in bottom so water can get out.
 
Ok I am thinking about buying this two pack. I am really stuck on whether I should purchase it or not. The price is unbelievable. But perhaps the SMD LED board is not up to spec. Can you guys examine this picture and tell me if it looks like a good buy? The product has lots of pictures to back it up. Plus i get two if one fails in the rain again and I will have a back up (UNLIKE NOW, ALMOST HIT BY A CAR TWICE YESTERDAY AT NIGH!) This could be a cool experiment I suppose but why do the LEDs look diferent than the boards in the orginal post? Look carefully, and thank you. I've been getting burned on aLI express a lot lately(why is that?), also here is the link to the product if you'd like to take a look.

https://www.aliexpress.us/item/2251...664740313!sea!US!0&curPageLogUid=5D7vPSaviVai chineselights.png
 
Also do you guys see the black octopus thing on the board? It has a huge dab of silicone on it. One does and one doesn't.

Edit: Ok as luck would have it I was somehow able to find out what the thing is called. I beleive it is called an IC chip, here it is pictured on ali baba. IT is ok to put a dab of silicone on that ? seems like it helps a lot in waterproofing this LED SMD board. The one I got from new egg didn't have the IC chip with proper waterproofing. NEed to send it back

I don't know?
Here is a great place to learn about lights.
Candle Power Flashlight Forum
 
From A TO B,

How about this light? you say "spend more", but I don't necessarily see that as the best solution here, How about this light though? I feel very afraid to purchase it considering the price and it's coming from CHINA with no reviews. I fear the WATERPROOF CLAIM is a lie and also that it might overheat because of how bright it is and it has no fins.


OOOO that;s monster bright if that's real! :twisted: I have to worry about charging deer here all the time
 
 
YEah marty you are probably right. Best to play it safe with that $36 dollar grin, but shipping from CA hurts. I wonder if I can find the same light on amazon with free shipping. I like how the beam pattern issue is already taken care of. That's a feature I would pay good money for.

Oh yeah I am terrified of theft too, many times I have come back to my bike to find my lights stolen or horribly mangled. They almost always rip them off, but a few times they have unscrewed stuff. That;s why I don't want to spend too much
 
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In one post, you’re “afraid” to buy a $9.24 light because it’s too cheap to be decent, and in another post you’re excited to buy a $9.24 light because it’s cheap and claims to be wicked bright.

Cheap electronics are cheap electronics— it either works for a while before dying, never works in the first place, or maybe works forever because you get lucky. In any case, you can’t be upset about it because you spent ten or twenty bucks to have a gadget designed, sourced, produced, assembled, packaged, and shipped to your door from around the world.

Either way, on the topic of very bright bike lights— be sure to have your light aimed correctly and, if possible, stay away from any product that provides a flood-like beam pattern if you’re going to be on the road. Super bright, scattered lights that fall into other’s eyes is a rude move. It can be dangerous for you, other drivers, and other bikers if you hinder their ability to see with a bright flood light on your bike. Best bet is a light with a lens that focuses the beam.

I’ve enjoyed using this in my bike. It’s not what I’d call “extremely bright,” but it puts light right where I need it in the road and is good for nighttime riding up to 20mph, which is plenty for me.

 
I’ve enjoyed using this in my bike. It’s not what I’d call “extremely bright,” but it puts light right where I need it in the road and is good for nighttime riding up to 20mph, which is plenty for me.

This is the main thing that differentiates the cheap light from the expensive ones, but sometimes you can find a cheap light that works well. It's not the electronics, since the LED chips and current drivers are a dime a dozen and contribute very little to the cost. Cheap light makers aren't going to focus on the beam/lens/reflector, they will put their efforts toward lumens, since that's what sells. The higher end lights focus their R&D on reflector and lens design.

 
A to B:

How does the horn work on that? Loud enough for cars?

E-HP: I GOT BURNED so Bad, they didn't even give me the proper LED CHIP or engine
Loud enough for pedestrians, and cars at a stop light. It’s loud enough to hurt my ears, but it takes even more if you want to get the attention of people in metal boxes at 25mph.

I initially was excited about having a horn. (I ride in places with minimal bike infrastructure and many cars who don’t know what to do with bikes.) Now, I never use it because cars can’t hear me, so I try my best to be chill and avoid situations where I’d want to honk a horn.
 
Loud enough for pedestrians, and cars at a stop light. It’s loud enough to hurt my ears, but it takes even more if you want to get the attention of people in metal boxes at 25mph.

I initially was excited about having a horn. (I ride in places with minimal bike infrastructure and many cars who don’t know what to do with bikes.) Now, I never use it because cars can’t hear me, so I try my best to be chill and avoid situations where I’d want to honk a
Yeah, I dont think horns are really ever used other than to be a prick
 
Ok

I have a new idea. Since you guys say that water just needs to 'get out' of the device, how about I get a step down converter and use this. The + - pads are so far apart I don't see this thing shorting out, and it says in the spec sheet it can be used outdoors.


I am buying this anyways. I think the $3.55 is just the purchase price of this. (it's possible that it may have more than one LED in the package. I might be able to use an extra LED for THIS PROJECT) A voltage regulator is only $10. I can wrap the voltage regulator in plastic when it is raining out. I also want to get an LED string and wrap it around my mid tube.

I will need a reflector, can you guys tell me where to get a reflector for that LED? That way the light will become far more useful.

How can I mount that LED onto a screw plate? I don't see any drill holes on the board.

DO step DOWN converters GET HOT HOT HOT?
 
I found two waterproof lights in my junk pile. They are both 6v but I was able to wire them in series. I am testing both of them right now to make sure they do not burn out after just 8 hours of use (I just dont want them to burn out) I will need to purchase a step down converter that is WATERPROOF, theftproof, and goes down to 12V. I might also get an another 12 V led light strip. As long as as I can Mount these lights I think this will work
 
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