This is where it started working at, is it ok to work it at this vacuum pressure ?? Is there any risk of the glass imploding ?? thats over 1 bar, unless that gauge is not giving a correct measurement
I think youâre all right with - 1bar. Just make sure youâre bf mixture doesnât pull over to the evaporation flask and watch out for a backflow from your pump cause itâs one stage it has an off change of a back flow of oil⌠I think.
When I first got my re-501 I was using a bvv dry ice cold trap with my 2 stage 12 cfm and regulating the vacuum pressure with the handle on the cold trap. I also used to go all the way up in vacuum close it off and let it just do its thing under full vac until it looked like the condenser was looking like it was slowing down then I would hit the vacuum again and hold a regulated vacuum of - 0.8bar for 5 mins before going back up to - 1bar and closing it off. Idk if that was super dangerous or not but it worked really well.
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Iâve been at a 2l roto all fucking day. Your pump is plenty fine (until you get a diaphragm pump) as others stated change the oil every day and let it work as long as it will.
At that vac level and 50°c on the water bath you should be moving vapor. Your pump will eat a lot of your ethanol (assumed) but try throwing some dry ice in your water bath.
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wtf is wrong with hooking a jet engine to a bicycle?!?
Edit: @Rowan guess there might be some valid reasons for not hooking a jet engine to a rotovap after all Roto Evaporator issues - #14 by cannabuilder
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nothing wrong except your expectationsâŚ
did you ask the all knowing one at what temp you might expect Ethanol to boil at those pressures?
or what pressure youâd expect ethanol to boil at 40C?
edit: and no, youâre not going to implode your glass. the ethanol will boil firstâŚ
note: ethanol boiling point under vac chart
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700,000 microns is where it starts to get sketchy⌠
Edit: I forgot the italicsâŚ
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Everybody should definitely watch more Colin Furze. SPINNING BELT OF KNIVES - YouTube
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I have a welch diaphram pump that would work perfectly. I use the same (I have 2) that I use on my 5l rotovap.
No oil changes or issues with burning the pump up with a diaphram vacuum pump.
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Grab yourself one of these Gast pumps. We run one on a 20L roto with no problems itâs also super affordable.
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It will also help to keep alcohol out of your pump if you just barely open the valve with the blue air filter it will act like a vac regulator and keep from soaking your pump and over loading your cooling set up
Toollots.com has diaphram pumps for a good price. We have one and a welch that cost twice as much and is only a single piston. Toolots is 2 for cheaper
Greatest effing sled ever,
Guy on jet bike, laughing-
" omg this is unstable! "
Everyone-
Yes, it is! Ftw! 
Cold trap?
How much solvent is it inhaling?
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Cold trap in this picture is not set with glycol.
Cold trap? Where?
I see the condenser in your Rotovap, which doesnât seem to have glycol in it. I donât see a cold trap.
Without a cold trap, you will be pulling solvent into the oil of your pump. They donât like that. Rumor has it that they can get pretty pissed off (spit fire in your face) if you abuse them thusly for long enough.
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Always wondered what would happen when that pump got hot enough with all those ethanol vapors passing through. I pull way to much solvent to not use a cold trapâŚ
The real issue is how hot they get once most of the oil has been replaced with ethanol.
Iâve heard tell of one that apparently reached auto-ignition, just as someone was getting around to addressing it. My understanding is that they recovered from the burns, but did get a face full of flaming oil/ethanol.
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Lol thank you for correcting me. I actually meant to type âcondenserâ not cold trap.
And yeah this picture is not updated Iâll post with glycol. Also, thatâs one thing we do, change oil often. Just like with any other equipment set up with vaccâs.
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