Thanks! Another one worth having if you deal with outdoor electronics is the transparent conformal coating type glue, that's very useful if you need to protect circuits from moisture.

@@voltlog Very true but I already got the conformal coating spray I learned about on your earlier video + a jar of potting mass bought from the same local store. It just occurred to me, would the white glue be good for securing a PCB to an enclosure (plastic or metal? Ideally I'd like to use standoffs but I've had trouble finding a suitable glue to make them stick on to the enclosure...

Ristomatti Airo Definetely worth a try. It might also help if you rough up the surfaces before.

@@voltlog BTW, the seller I ordered the adhesives sent me a message they won't ship through AliExpress Standard due to "increasing difficulties getting liquids past security checks" and they they'll use PostNL instead. Did you get anything like that?

Myself I prefer to use hot glue with foam planes because I don't have to wait for it to cure for a long time. K704 for example, whenever I use it as conformal coating, it takes at least 12h for it to stop being sticky on the outside.

@@voltlog, yes, hot glue is also very useful for quick repairs. But for building it is often too heavy and to fast for assembling large parts.

@@jean-paulisambart2444 I am thinking of buying some of this 704 glue to help repair my foam plane. It was used in the factory where my rc foam plane was made so I prefer to use the same glue for repairs.

Glad it was helpful!

What would be the best way to do this?

@@jacobscoville2044 well I would imagine that you have one surface at a fixed temperature, you apply a known thickness of paste, and then you attach another surface with temp sensor, and measure the temp after a certain period of time. Something like that.

Thank you! Cheers!

Ok, good to know that the K586 is acid neutral cause out of the bunch I've tested so far I was unsure of this one. It had a different, more powerful smell than the others.

@@voltlog Yeah there is definately a chemical curing reaction with the air. The difference between this silicone sealant and others if that it is 'neutral cure" meaning neutral ph. This is documented on wikipedia as being 'oxime'. Which refers to the chemical reaction. All 'oxime' silicone sealantss should be safe for use with electronics (bnot to damage them by acid). For example WP70 Neutral Cure Oxime Silicone Sealant i also have here. And also another one I can buy here in UK is called "SSG4000E UltraGlaze". The reason to get those instead is to do with the properties. A low modulus (LM) silicone sealant is typically most of the oxime ones, Which means it's more elastic and deformable. Reading the data sheet I suspect perhaps the "SSG4000E UltraGlaze" is harder and more durable. However I have not had the opportunity to use it yet. ALSO these large caulking tubes they come in are very large and difficult to push out, Another big problem is that after about 1-2 years they will harden inside the container. Or if you have started to use it, then and air gap in the tube will cause the entire thing to harden into a solid tube,But there is more! Necause in Europe we also have products things like "ONEGel" and "MP Gel" if you search for "silicone electrical potting gel" and this is designed for electricians, when you need to put wiring outside you can fill the entire electrical box with this silicone gel. To protect everything inside from the weather. For example if you want to install garden outdoor lighting. This is also a very good alternative to a conformal coating. Hopefully that helps you to understand why the black one still smells because it is "oxime" type. This is a different smell comparing to the regular construction silicone sealants. Which have ammonia that smells much stronger, and then the PH acid from the reaction will then chemically damage the PCB (like an active flux). Don't worry! The black oxime ones are supposed to be safe for electronics. It is the correct product to use. For sure. I also looked for other neutral cure sealants that were not "oxime" type. However they are not available. So basically all of the "neutral cure" are oxime type. So just check for "oxime" on the label to make sure. Otherwise search for "silicone electrical potting gel" in google.

@@dreamcat4 thank you sharing this knowledge!

Screw it my friend

Do you think 705 is the right one for full cover waterproof radio board and regulator of R/C car ? Cheers

I think that will work fine. Cheers!@@MACYNET323

How did the K-705 worked for you? I'm thinking of buying it to use on a capacitor.

@@joaosilvestre1468 I can't really say as I don't use that USB light really often, and not much long so it barely heat. All I can say is that it add a nice layer of smooth silicone on the PCB which protect the components if you put it on your keychain for exemple.

@@abc-iq9fk Cheers. I actualy realized that the glue I need is not the K-705 but the K-1668, the yellow hard one.

I would think general silicone adhesive rules apply. After it's been opened, you need to seal the cap as best as possible to prevent it getting into contact with air/moisture.

One general rule for keeping most glue tubes longer once opened is to seal them with a small piece of metal tape before screwing the cap back. It can be aluminum or copper tape. This has worked for me on many different types of glues.

Kafuter actually makes this too! K-5203

Canadian Tire carries these in Canada. Part #067-0852-4 Home Depot in US sells them, but not in Canada. 1st time I see that! I like these tubes. They don't get as clogged on re-use, from using small amounts at a time.

@@ufohunter3688 I actually use the product that is specified as "glue" as opposed to "sealant". Seems like the same product but, I'm not sure if the formulation is the same. I work on tube amps that get hot and don't want it peeling off. For some reason the large home improvement stores don't sell it. www.amazon.com/Silicone-Household-Glue-Seal-GE280/dp/B001JK7OJA

that stuff has a very short shelf life

I only buy it when I need it for a job and use it up quickly. Don't know what else I could use to glue down components?

@@acoustic61 you could use products that are designed for the purpose. I don't like throwing away things I spent good money on because it didn't last, or I used once. I also like to have supplies on hand, and not having to drive to a store when an idea strikes. (or waiting until they open)

No worries!

It does look suspiciously similar. I found references to "chloroprene glue" when people were discussing corroding brown/white PCB glue. This glue is described as "Hengda Kafuter K-1668 Yellow Chloroprene Rubber Adhesive", so, I think thats enough of a sign to never use this stuff. Unless its just for a prototype or similar.

I seriously hope it's not the same stuff. To be fair that problematic yellow glue was probably at least 10-15 years ago so things have changed since that happened. I have seen yellow glue on many modern electronics, think about all wireless routers, they all have yellow glue inside to hold either the small U.FL connectors to the motherboards or some small coax which is soldered directly to the motherboard.

Nice english bro. You must be really smart to know only your native language 😂

@@CaltaTomas кому надо, тот переведёт в гугл переводчике или нажмёт кнопку "перевести" + плагины к браузеру никто не отменял. Но нужно быть рили смарт, и не быть тобой, чтобы это понять..)

@@AlkoSeltzer bruh 🤣

Electronics safe silicone should be non acidic.

@@NiHaoMike64 Yeah, hence my question. The ChiComs aren't known for doing things properly.

From this list, they don't smell like vinegar, so I would guess they are neutral cure. Only the black K586 has a slightly different smell but that one isn't recommended for directly using on electronics anyway.

@@voltlog Thanks, that's good to know!

I've been using K-5905 for several years in this application (potting) and it has not caused any problems nor does it have any smell.

Could it be a case of mechanical stress? because the the glue might put mechanical stress as it contracts during curing. I have seen some pretty sensitive LEDs, especially the cheap ones from no-name brands. They would decapsulate at the slightest mechanical stress.

@@voltlog I think yes. Cause the glue shrinks a lot while curing. Even if the LEDs look ok underneath it

why would you use epoxy on the leds? normally you want them to sink the heat, not prevent the heat from dissipating.

@@stanimir4197 the tiny ones like 0604 or 0402, to make little wrist watches. You don't want solder to be in contact with anything, it's poisonous

He said BGA under fill. Just different accent. ;)

He was saying "BGA underfill" (ball grid array).

I can't say I've heard of BGA underfill. I've seen most reflowers just drop balls into a stencil and put the BGA on top. Is this underfill that glue that they use to hold parts when doing a double load PCB, ie, for parts upside down.

BGA underfill: a type of epoxy which is designed to mechanically secure a BGA to a PCB. It ca help with chips that run hot because it helps prevent the effects of thermal expansion or flexing in the PCB. Generally a laptop motherboard will have this around the CPU, GPU.

If you heat it with hot air, it will become soft and remove easily.

@@hhKJgf1M8a0rzt8hP Thanks. I would try that if I had to do it again. I just chipped it off, took ages, but it stopped my Subwoofer from making stupid noises... Well, either that fixed it or changing a broken diode did, not sure which did it.

@@Lloyd.B. I'm currently working on a Philips HTS9140 soundbar. PSU board is full of this stuff. On some of the polyester film capacitors, legs (the ones in direct contact with this adhesive) have been corroded to such an extent that they broke apart.

@@hhKJgf1M8a0rzt8hP People really need to stop putting it in anything - it should be illegal lol. Surely there is something better - ie something that does not start conducting electricity when it gets old >.

@@Lloyd.B.Yes, I agree. Devices get trashed prematurely because of a mistake like this. I normally use polyamide hot melt for securing elements on PCBs and for high heat applications I use Kafuter (the white one). So far so good.

It certainly has a similar yellow color but to be honest I haven't heard of that type of corrosion issues happening inside equipment produced in the past 5 years so maybe those kind of problems are not present anymore. I don't know, just guessing here.

It's like the usual threalockers, different color means different hardness levels. It seemed like testing one of them would be enough.

...... Tom Hanks used it all !

Does it actually mean anything in German? Sure "sounds" German but does not seem to ring a bell on my German vocabulary. ;-)

I need to practice that 😂