The goo/plastic/elastic stuff to avoid vibration for capacitors on PCB ? - Page 1
Forum section: electronics / beginners

author: anotherlin
author_rank: Frequent Contributor
timestamp: April 09, 2015, 03:17:10 pm
content: Hi everyone,I'm wondering where I can buy the goo/plastic/elastic stuff they put around capacitors on PCB to make them not move when everything vibrates ?This is often seen on name brand or high end bench power supplies. I can attach a picture if needed.I've tried to look up on mouser or farnell, but don't even know the name of the stuff.Thanks.

author: ConKbot
author_rank: Super Contributor
timestamp: April 09, 2015, 04:04:21 pm
content: Cheap power supplies, hot glue, better power supplies, RTV silicone, acid free/neutral cure. If youre doing hobby/one off stuff and you want it locally, "Sensor safe" RTV silicone would work(auto parts store), as would GE silicone II bathroom sealant (if youre in the US at least)

author: wraper
author_rank: Unknown
timestamp: April 09, 2015, 04:14:15 pm
content: At Farnell - ACC silicones AS1700 white high viscosity stuff, AS1821 - black self leveling, AS1723 - transparent self leveling.

author: jlmoon
author_rank: Unknown
timestamp: April 09, 2015, 04:39:22 pm
content: http://eclecticproducts.com/products/e6000.htmlPretty good stuff.

author: corrado33
author_rank: Frequent Contributor
timestamp: April 09, 2015, 04:47:39 pm
content: Also, if you're going to use hot glue, make sure you use the "hot melt" stuff. The normal "low temperature" hot glue will melt if it's next to anything even remotely warm on the board.After it melts it likes to drip on to cooling fans, ruining them and making your power supply shut down due to overheating.Ask me how I know.

author: tszaboo
author_rank: Super Contributor
timestamp: April 09, 2015, 04:48:59 pm
content: Yes it should contain sealant, silicone or RTV in the description and "electronics" in the datasheet. Dow Corning has an entire range for this 7xx.

author: TimFox
author_rank: Super Contributor
timestamp: April 09, 2015, 05:44:40 pm
content: Quote from: ConKbot on April 09, 2015, 04:04:21 pmSilicone "bathroom sealants" should be avoided since they may contain anti-mold toxic ingredients.An easy silicone to find in small packages is "Elmer's Stix-All Household Cement".

author: robgambrill
author_rank: Contributor
timestamp: April 10, 2015, 06:34:28 am
content: I agree, avoid bathroom type silicone. GE and other brands I have seen contain vinegar (acetic acid). Found out the hard way, that corrodes copper.

author: anotherlin
author_rank: Frequent Contributor
timestamp: April 10, 2015, 12:28:49 pm
content: Hey thanks for all your answers.I've actually done some "home improvement" on my bathroom, and I'll definitely won't use the bathroom sealant for anything else than bathtub. It stinks!I've taken a look at the datasheet of the AS1700 available at Farnell. It seems it's designed specifically for "electronic assembly", so I guess I'm gonna give it a try.By the way, it's pretty expensive, 30 euros or so for 310mL

author: ConKbot
author_rank: Super Contributor
timestamp: April 10, 2015, 12:57:14 pm
content: Quote from: TimFox on April 09, 2015, 05:44:40 pmI'm not eating nor licking my PCB's are you?It shouldnt present any more risk than being used in a kitchen, or bath, just avoid using it on potable water containing items, or aquarium related things.Quote from: TimFox on April 09, 2015, 05:44:40 pmNot silicone, potentially useful for the OP's application, but still not silicone.Quote from: robgambrill on April 10, 2015, 06:34:28 amGE silicone II is neutral cure, not acetoxy cure(the vinegar smell), GE silicone I is acetoxy cure, avoid it.

author: Bassman59
author_rank: Super Contributor
timestamp: April 10, 2015, 04:11:49 pm
content: Quote from: robgambrill on April 10, 2015, 06:34:28 amOh, yes, and if you don't leave the window open while doing the work, your bathroom smells like a salad or a photographic darkroom!

author: robgambrill
author_rank: Contributor
timestamp: April 10, 2015, 04:13:24 pm
content: One of my first projects was a moisture alarm (I think it might have been based on a circuit from Radio Electronics Magazine), tried to seal over the solder points with GE silicone that smells like vinegar and it ate the board and wires over time. Newbie mistake on my part. Will have to check out GE type that does not have that problem. Thanks for pointing this out.