What is highest micron possible to have successful SPD?

I have a 2L Shortpath system with a 9 cfm pump and I can get it down to about 125 micron with a dry run but in the first run I did it fluctuated between 425 micron and 1000 micron depending on the temperature of the mantle and head. I seem to have gotten “ok” color and quality oil so im not disappointed but I guess I would just like more info on the vacuum portion of the process. Any help would be amazing guys. Thanks in advance.

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Search bar awesome here!

Maybe this helps until you can get more defined answer but , great reading!

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I did read that article and it was the basis of how I did my first run. I loved the amount of detail that author had for the benefit of all of us. My pump isn’t as good as the author of that post so I guess what I am asking is if my pump is able to displace good enough numbers for a 2L short path.

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It looks like your pump is more than adequate. If you decarbed your oil better and filtered it a tad better you might not see the micron swing from 100 or so to 500 or 1000.

When you hit the cannabinoids, what’s your micron level then??

Sounds like your vacuum level is fine though. How are you decarbing? Are you decarbing up to 140c and under vacuum.

What kind of cold trap do you have as well and how are your running it. Acetone/dryice slurry? My vacuum levels literally ended about 50 microns from what mine started and it didn’t swing at all. It just slowly climbed to about 340 micron and then went down a few.

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You can have a successful SPD with 300 micron although you want lower. Your dry run vacumm is too high and you have to do it with full cold trap and even dry ice on receiving flask. Also you want to check better for leaks and are you using grade 19 vacuum or better? Vacuum oil is the key to deep vac, grade 20 or better. What about the ballast you should close it. Also it seems you ran first pass? Second pass has lower vacs.
All of these together should work. Also change oil and check vacuum direct attached to monitor to see real vacuum.

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Your va cuum lines should be as short as possible and bellows work bettter

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What are you doing for cooling surfaces? Having adequate count surfaces is critical to deep vacuum.

2 pumps work better than 1
First fir the light fractions and 2 for the cannabinoids
And of course a difffusion pump or turbo Molecular pump

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when I hit cannabinoids I don’t really remember what my micron level was I believe it was around 400. When I decarbed I only left it on a hot plate slightly under 128 degrees F and just let it bubble off. Is the better way to put it in the mantle and put it under vacuum under 140C until it bubbles off?

I have a full bore glass cold trap and I have 24/40 adapters to GL-18 connectors to go down to my pump. I bought full bore so that once I upgrade up to a bigger vacuum pump I can go straight from kf25 to 24/40. I use dry ice with acetone to keep it cold. I did not know that I should be using my vacuum dry run with dry ice in it as well so that is really good to know.

By the way, it is so amazing that all you guys replied to me and I feel so appreciative of you guys just so you know… thank you

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I do use vacuum 19 oil and I did not know to have dry ice for the dry run of the vacuum I will try that ASAP to see what I can get down to. I also just bought Apiezon h150 I believe its called that summit recommends. do you know if this is great grease for sealing up potential micro leaks?

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I did read one of your other posts about how you use two pumps on the system to make things easier. I am planning on getting an Edwards m30 pump and using my existing pump to have the two pump system you are recommending. I think that would work out.

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Both pumps have to have the same performance or it wont be as edficent as tour hoping. Like buying 2new pumps or checking micron on both pumps after having them rebuilt. I do first pass below 40 micron and 2nd at about 10 fibe or take depending in how hard im pushing the system. Get a roughing or a theow away pump that you use for firsg pass up to about 150-60c and save your good pump for the good stuff

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The apezion is very expensive. If you can’t get below 50 don’t buy it. We use it for deep vacuum only.

Worth paying a bit extra for a greater vapor pressure oil, -6 suggested, lube the joints with apezion 501, (make sure you knead the tube before application,) heat pump/oil up with ballast open for 15 mins,BUT remember to close it , tighten clamps/wingnuts (assuming you’ve made the choice to go full bore, kf25 sst) go online…SHOWTIME😊

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yes I tried it last night on my 2nd run and it was just ok but I also was around 500 micron the entire time but I didn’t notice to big of a difference. I didn’t know about the -6 vapor pressure oil so I will buy that ASAP to get that going in my pump as soon as I can

Ok start from the top what brand pump?
What size and model ?
Have You tried Reading vacuum on the pump itself ?
Then on your system ?
500 for Any two stage pump smels like a leak Some helium from the ballon shop can help You find iT

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What is -6 is that a vacum oil. I use 19 and havent heard of anyone reliably saying 20 is better.

How do you test for leaks with the helium?

While your system is running you pass a stream of helium past your conections from all sides the helium heen sucked in Will make your vac gauge give a spiked faulty Reading all of a suden

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Thank you! That helps a lot when working with glass from different sources!

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