Any recommendations for small vacuum chamber to de-gas 4L epoxy potting compound - Page 1
Forum section: electronics / general

author: Psi
author_rank: Super Contributor
timestamp: October 03, 2025, 03:32:52 am
content: I'm in the need of a vacuum chamber and pump to de-gas epoxy for pouring potting compound.Does anyone have any recommendations? Any aliexpress ones that you've tried and are ok?I don't need top of the line or anything. Just needs to do the job. I'm going to to be pouring around 4 liter / 1 gallon at a time. So doesnt need to be huge in volume.Budget probably under NZD$500 / USD$350 but flexible if i need to spend more.I'm guessing the pump quality is the thing to watch for.Maybe get one from Aliexpress and replace the pump locally if/when it fails?eghttps://www.aliexpress.com/item/1005008612803938.html

author: Cyclotron
author_rank: Unknown
timestamp: October 03, 2025, 04:47:42 am
content: I bought my vacuum pump on ebay and made my own pot with a stainless pot and plexiglass lid.But there's an industrial recycler near me that has stuff like the pumps all the time for cheap. A used HVAC vacuum pump would be fine. Might want to change the oil to know its state.I made my vacuum pot with a stainless pot I picked up at the second hand store. the Plexiglass was found at the hardware store.

author: cunningfellow
author_rank: Regular Contributor
timestamp: October 03, 2025, 04:53:09 am
content: I have a "Best value vacs" one bought many many years ago when options wewre slimmer. I got a Robin Air pump locally.These days I would just get a Vevor. They never have the worst quality and are the easy option.

author: Jeroen3
author_rank: Super Contributor
timestamp: October 03, 2025, 06:00:36 am
content: I have one of those €150 vevor ones because i needed one for an experiment.It works, doesn't pull that much of perfect vacuum of course, but I think for potting it's fine, which is what I used it for.It is cheap, so you get what you pay for.Perhaps the bucket it comes with is not big enough for a 4 liter container, it may foam to the lid, you don't want stuff to enter the compressor.

author: Psi
author_rank: Super Contributor
timestamp: October 03, 2025, 10:03:07 am
content: Yeah, you're probably right that i should get one a bigger chamber to account for it foaming up

author: Psi
author_rank: Super Contributor
timestamp: October 03, 2025, 10:17:14 am
content: I'm wondering if I should move to soft silicone potting instead of epoxy.As i understand it de-gas'ing the product before use is less of an issue with soft silicone? So doing it is more optional than with epoxy.And the hardness of epoxy below 5deg C is a little concerning with regard to thermal expansion.Anyone have a wisdom to share on the subject?Out of interest, how hard is it to remove soft silicone potting compound from a PCB? Can you peal it off and rework? (Rework is obviously not possible at all with epoxy)

author: Accu-Sembly
author_rank: Contributor
timestamp: October 03, 2025, 04:56:16 pm
content: We use something like this from Baco.https://bacoeng.com/products/vacuum-chamber-kit

author: thm_w
author_rank: Super Contributor
timestamp: October 03, 2025, 08:08:02 pm
content: Is there Vevor in NZ? They have lots of this stuff.Quote from: Psi on October 03, 2025, 10:17:14 amYou can but its a huge pain in the ass, crumbles apart. There is the soft "re-enterable" stuff that Dave has shown before, if you have pots that need adjustment, etc.https://electronics.stackexchange.com/questions/415303/can-you-tell-me-more-about-re-enterable-potting-compound

author: Jeroen3
author_rank: Super Contributor
timestamp: October 07, 2025, 06:54:38 am
content: What are you potting?We pot electronics, but never degas. Just use the two-cup mix and careful pour and that avoids a lot of bubbles.But our product is not exposed to any extreme environment, just vibration, so the bubbles aren't that critical.If you need IP or pressre rating by potting things may get more complicated, you may need to pot in vacuum for that.(We only pot specials and prototypes ourselves, production is outsourced and they have a special mixer nozzle)

author: Psi
author_rank: Super Contributor
timestamp: October 07, 2025, 08:48:44 am
content: i'm going to switch to soft silicone compound, (unless the price comes back crazy high, just waiting to hear back from alibaba seller)So de-gasing is less of an issue now.Thanks for all your suggestions.