First pass questions

So I recently convinced my boss to purchase a digivac vacuum gauge after a strong suspicion that the vacuum wasn’t pulling to the correct micron. I was correct it is reaching about 15 microns when capped with the gauge? Best to rebuild or is there any remedies? Just tryna figure it out was supposed to start some distillate today but I’m currently pulling vac on the SP and it’s at 1840 microns… Please help lol?

Well if your pump is pulling 15 and your sp is pulling 1840 you have a pretty serious leak. The easiest way would be to get a tank of helium from walmart or anywhere else that sells those party ballon kits to go for $18 or so. And start testing all your joints and fittings.

Its $18 and you will need only one or 2 ballons filled…


Turn the lights down in the room and run a flashlight across your joints and see if you are picking up any vapors, trace down the leak and seal it, if that’s the case.

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Regressed all my joints at 385 and still falling a little 382 by the time I could type this

366 seems to be as deep as I can get

what about your thermometer probes…this is where my problems where


I just taped it so we shall see thank you

Get a thermo well for the head probe and get a wire probe to control temp from the outside of the flask. I went from 300 on an empty system to 39 by doing this and going full bore.


You just capped your second port on your BF and used a external flask probe and then used a probe in the head? Any chance you could link the head and flask probes?

anyone smarter than me know what this is? The drops were clear and became red after I broke vac to change my flask I’m assuming its oxidation and they are probably terpy junk just curious if this batch is ruined or will be remedied with a 2nd pass? And how do I avoid it in the future? Thanks again guys


Yes, I capped the second port with a stopper. This is the well for the head. Your normal head probe goes in there. Just remember that the temp it shows is 2 degrees colder than it actually is inside the head.

The wire probe looks like this. I have another one, but they should work the same. Make sure you try several places to make sure it reads results close to each other so that you don’t get a cold spot. I got one when I was using my regular probe, before I got a wire one and that run showed 156c on the mantle with the head temp at 186c. It was mighty confusing.

I will tell you that this requires you to read the head temp more and I’ve found the exact temps that work for me, but they are vac related so it differs for everyone. I did do test runs to measure both outside and inside the flask to grey a better understanding of the difference between them. By doing this you pretty much have know what’s going on in the system cause you won’t know the temps inside the flask which is what everyone is referring to. So now I know that 175-185c outside the flask is where most of my volatiles are done. Then I slowly go up to 200c mantle and when the head gets to 160 I switch to main, then it reaches 168 and stays there. Roughing pump is then at 400 micron and after switching pumps it’s 200 micron and steadily dropping to around 100. But this is just how I do it. Your parameters will prob be slightly different.