From the APT site.
30" Vacuum = 0.0 mmHg (Torr) = 0.0 microns = Perfect Vacuum
0.05 mmHg (Torr) = 50 microns
0.1 mmHg (Torr) = 100 microns
0.5 mmHg (Torr) = 500 microns (Resin is degassed at 50 to 500 microns to vacuum
pot and encapsulate high voltage components.)
1.0 mmHg (Torr) = 1,000 microns (In-chamber vacuum levels from 500 to 1,000
microns are required for most vacuum potting and encapsulating applications.)
2.0 mmHg (Torr) = 2,000 microns
5.0 mmHg (Torr) = 5,000 microns (2 to 5 mmHg is needed to make low to medium
viscosity resins visibly air-free. This range of vacuum levels is five to ten times
better than 29" of vacuum.)
10.0 mmHg (Torr) = 10,000 microns (Very little degassing is done at this level.)
29" Vacuum = 25.4 mmHg (Torr) = 25,400 microns (Not a sufficient
vacuum level for degassing most epoxy and urethane resins.)
28" Vacuum = 50.8 mmHg (Torr) = 50,800 microns
15" Vacuum = 381 mmHg (Torr) = 381,000 microns
0" Vacuum = 762 mmHg (Torr) = 762,000 microns = Ambient Air
I saw this and said what??the hec?I think we are reading the charts wrong.I think possibly they mean 29"will not de gas the epoxy formula.E/G if you were de-gassing polyester,29"would boil out the styrene and ruin the chemistry.Max for polyester is something like 25"
Cameron from the Mechanical Engineers hand book,29.9 again this must refer to what point the epoxy vaporizes.If so this would translate to epoxy is safe to de-air at perfect vacuum.Perhaps we are using the wrong terminology.
De-gassing is different from De-aring?
Only guessing,but 25"should be sufficent for De-airing epoxy while mixing.
I will try to research that later.Late for work.
A cheap Gast pump should be able to do the job.
A realy cool item is a vacuum bell jar.You can see your mix boiling.
Larry