Size to the mix you degas in one batch
Buying guides often show chamber photos without mapping your mix gallons and foam headroom to chamber volume. VacChamber starts from mix volume, then applies a foam factor used in workshop degassing practice.
Why this ladder is only 3 and 5 gal
Verified VEVOR US vacuum degassing chamber listings checked 2026-09-10 sit at 3 gal and 5 gal. Other mid sizes exist but are outside this site’s verified ladder. This is separate from HVAC vacuum-pump CFM sizing.
What SERP guides miss
Most pages compare brands or explain vacuum pumps without an interactive map from mix gallons × foam factor to a purchase class with an explicit NO_MATCH path.
Practice rules this screen never relaxes
Leave foam headroom — do not fill the chamber brim-full. Confirm lid seal and pump compatibility on the listing. Ratings are manufacturer claims — verify the listing. Affiliate tracking is pending.
Class ladder on this site
Required chamber gal ≈ mix_gal × factor. Factor 2 for typical epoxy headroom or 3 for silicone/heavy foam. 3 gal class if required ≤ 3; 5 gal if required ≤ 5; else NO_MATCH. Specs checked 2026-09-10 on the linked product pages.