What should I change, bad results!


I really like learning about this stuff


From what I’ve read in organic chem books, they don’t work under vacuum.


boiling stones will not work under vacuum, the stir bar is used to prevent superheating of the liquid.The takeaway lesson here is even heating vs nuculation sites.


Really cool information on pressure vs curvature and the way those nucleation sites work. I didn’t know it was trapped air doing all the work! I originally thought the stirp bar was just to avoid hot spots, but now i know more of its uses, thank you @cyclopath and @Soxhlet


I havnt been heating the fullers or charcoal other than what the ethanol is heated to. My Welch pump has recently been unable to pull past 28.9hg. I tried messing with all the seals on the glass and hoses. All I’m using is high temp vac grease. Possibly the pump needs a rebuild or oil change? It does seem like my reaction is too strong. As if it’s climbs up the vigereux and pours through the condensor. I havnt done any second passes yet. I’ve been saving all my first pass to get it down pat to run all my second pass.


Does anyones distillate it volume go from black starting material into anything better than an orange clarity in 1000ml jar roughly finished?



You should be changing that every time you run that setup. Get flushing fluid and some grade 19 pump oil and you should be able pull deeper, hopefully.


Could you explain a bit on what procedure to use to clean out the oil after draining and before refilling? What to clean it with?


I can only picture my pump in front of me. I have one across my facility and I will go look in a little bit. I’m in the middle of recovery.

But there’s a drain port on the side. Run pump closed off for half hour - hour, until its hot. Open drain port into large jar or bucket (keep elevated on table or bricks). On the top there’s a couple spots to open. I Can’t remember which one. But, open em to vent and allow the oil to drain easier (like putting a whole in a water jug to drain). It’ll get low and tilt her to get all the oil out.

If you bought flushing oil, you would close the drain, pour some in (don’t fill it, though), swish it around and then drain it. Top off with fresh grade 19. Run till hot and repeat again with flushing fluid and refill. After the second time you hopefully will see improvements.

I say to flush her twice because you may not have flushed her before and she’s probably not very stoked. After each run you should change the oil. Depending on how you run. After you do your heads, change the oil and then do main body and second pass. And change again. Have that be your routine and you can extend her life drastically.

Your oil is going to smell disgusting.

You can get both the flushing fluid and grade 19 here.


Are you sure you can use that oil and flushing fluid with his pump. He has a Welch 1400. I thought these pumps require specific Welch pump oil??


I run grade 19 from usalabs in my 1400.
It’s quite a bit cheaper than welch brand oil.


Grade 19 is a direct replacement for the welch oil.

Only oil I have around here for the Alcatel I use. My vac ovens are on a dry scroll


Glad someone other than the salesman verified this. I already filled and ran her for a few mins after I got the pump.


Thanks for the information. I never knew the 2 oils were replaceable. That’s my lesson for the day.

I use vacoil 19 from vacoil.com too. Recently I’ve been buying grade 20 from the local vacuum pump shop for $35 a gallon.



Look at the brand equivalents


Probably a better price, too


I filter all the way down to .5 micron and if your only doing 8 micron thats where the cloudyness is coning from. Is it only cloudy once it cools?


What is the flushing agent you recommend to use? I filter down to 1.5-2micron the filters are rated. I solved the cloudiness I think by doing 1 more filtration on dry ice through the 2 micron.