The problem with fully removing solvent in a 20L+ rotovap is getting it out all out of the boiling flask in a timely manner.
One solution that works is replacing the glass boiling flask for a 12 inch stainless steel spool, reducer and custom flange allowing for the removal of the bottom cap but this requires custom fabrication and will put more stress on your rotovap’s motor and you can no longer see the flask bump, however if you know what your doing and have good vacuum it speeds things up considerably
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