so i landed myself a decent vacuum pump, after carefully reading into vacuum pump oil i just cant figure out what the actual chemical difference is..
to engine oil
except for maybe, that most engines uses a bit more viscious oil- while you can also get lower viscocity oil on the same shelf
https://www.repsol.com/imagenes/global/en/vacuum_pump_oil_tc...
" Resistance to oxidation, ageing, and sludge formation.
Low freezing point.
High viscosity index.
Compatible with gaskets.
Good anti-foaming properties.
Excellent anti-wear properties.
Good demulsibility."
on this site here they mention 10W and 30W, i believe lower W means its less viscious
on assorted forums they mention it has to be corrosion resistant (engine oil is)
it has to have low volatiles (engine oil has this, parrafin oil based typically)
https://www.evpvacuum.com/difference-between-engine-oil-and-...
"Anti rust and anti-corrosion: it can form a very effective anti-corrosion film on the metal surface, so as to prevent the system corrosion caused by
inhaling corrosive gas and water."
"It has low steam pressure to prevent oil from backflow and diffusion from pump cavity to vacuum system. So as to ensure that there is enough limit
vacuum."
dont oils- generally, unless contaminated have low volatility, aka.. steam pressure? i see no mentions of special vacuum oil additives, engine oil is
generally just parrafin oil reacted with sulfur so that sulfur in the oil will react with oxygen and protect the metal parts from corrosionmacckone - 10-3-2022 at 18:31
Vaccum oil is low vapor pressure first and other things second. It is usually very low viscosity and is mostly straight chain hydrocarbons. The
corrosion inhibitors in vaccum pump oil are usually focused on binding water and corrosive chlorine and fluorine compounds.Fantasma4500 - 11-3-2022 at 12:32
do you have insight into the formulations of these oils or a guesstimate on how difficult they would be to make yourself?macckone - 11-3-2022 at 15:16
do you have insight into the formulations of these oils or a guesstimate on how difficult they would be to make yourself?
Making is more expensive than buying.
I get mine at an autoparts store.
$10 for 32 oz
You could make it from baby oil.
Use an oxidizer to remove oxidizable compounds.
Vacuum distill.
Dry.
Add in an appropriate anti-corrosion agent.
Key features are saturated straight chain hydrocarbons.
High boiling point.
Relatively low viscosity.Fantasma4500 - 13-3-2022 at 06:15
so - parrafin oil would do, which is engine oil mostly. they do also contain oxidation inhibitors- which of course can be oxidized, then adding back
in the corrosion inhibitors just seems silly to me
as for corrosive gasses, could urea maybe be added in? i cant think of much else thats about as stable as that, that reacts easily with chlorine and
similar
i did come across one safety datasheet for vacuum oil where it just listed pure mineral oil
infact, i happen to have a bit of fancy shiny red hydraulic oil standing around which is apparently quite low viscocity, might report back if the
whole machine blows up
