Shatter is most definitely NOT all carboxylic acid! The THC-a is a pure carboxylic acid, but THC is an alcohol. What we know colloquially as "Shatter" is a combination of solids (THC/CBD and their cannabinoid cousins) PLUS terpenes, which are OILS at room temperature. Soft, flowing oils...
Add some oil to a solid and, if the solid is soluble in that oil (terpenes DO dissolve cannabinoids), then the solid will soften. It's that simple. Want rock hard shatter, then select high-thc strains...
Would anyone know y when I purge at -29.5 with the air release open up abit to maintain that exact pressure why my pump smokes oil abit out of the top where I put the oil? And it don't smoke when I close the air valve and bring the vac to max hg wich is around -31.5 hg / -32 hg around there?