14-18 hour shortpath run


Hey guys,
So i am running a 5 liter shortpath with a 1/3 horsepower edwards pump. I have been getting decent returns, above 65%, and great color but my runs have been taking an absurd amount of time. My last 1700 gram run took over 16 hours. We are saving up for a vacuum controller but I would love any additional input to decrease our run time.
a couple notes
we run the stirrer as fast as possible,
we have a monocow for the initial blue/green/terpenes
running a dewar cold trap
our cow swap is normally between half and a full minute
we have our cows in a dry ice bath
it normally takes about 2-4 hours of proper temperature scaling before we hit green.
we consistently pull our green at 190 Celsius and start reaching the head around 202-205.



this is a first pass run.



What is your vac depth looking like? How are you going about ramping up temps on the mantle?



So we follow summits suggested method. Where you ramp up in 20-40 degree increments allowing the temperature to consistently climb. We are looking for a gradual increase.
As to our vacuum depth, Its the next problem. When I switch the hose to the monocow to start going for our head fraction, I don’t know of a good place to place the gauge for consistent results. So I don’t know



Somewhere after the cow, and if you can put another right before pump. You’ll need to know your vac depths yo accurately assess what’s going on especially because it seems like a potential vac issue.



I could give you a bunch of changes, but nothing will be as good as upgrading to a wide bore system. nothing will change as much as getting rid of hoses…



My 1st disty run took about 12hrs for a 450ml heads return. My teacher (thanks again @PofH) had me go up 10c every 15 mins to get used to the fractions. I was a super noobie. My last run was 8hrs for a 480ml heads return. Adding in 1hr for setup and warmup time.

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How is the vacuum gauge reading? That reading matters in fraction distillation.

Hydrion Scientific Instrument

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Hi guys I made my first and second pass on our 5l china junk system. Did ok, I couldn’t get my vacuum below 1500 microns, running a edward 30. (dead head pump went down to 2) I got a good run. My questions is if i switch over to a big bore kit from LS can I get a accurate enough fraction so I can start Fractioning the away from my cbd? attached some data and pictures and HPLC readings seems like we were starting to pull oil around 210cUploading: IMG_0197.JPG…

Uploading: IMG_8863.JPG… Uploading: IMG_8928.JPG… https://future4200.com/uploads/default/original/2X/9/96d5e13c4da096d5a837c9b09956939a2f078a2b.mp4



I am looking at upgrading to a wide bore system. I have been doing this off of a budget BVV system. Would you have suggestions for a budget wide bore?
Would a vacuum controller assist as well?
Also I would love to hear any suggestions.



The primary reasons your run are taking long can be broken into two categories.

  1. User error
  2. Equipment limitations

Does your run time consist mostly of you ramping up temperatures or of waiting for the main body to boil out?

If it is mostly ramping up temperatures, then you just need to get to your fraction temperatures faster. If most of the time is spent waiting for the main body to boil out, then you may have a leak in your system. I ran a $200 vacuum pump on my 5L for the first year and my 2.5L runs would take 10 hours tops. With an e2m30 and the Lab Society HE head, my 3L runs only take a few hours at most.



Wide bore and an Edwards30, your problems will go away. I’m a fan of changing stainless and ptfe in wherever possible.

My Widebore kit right now: Total cost roughly $2000

-1x Summit Cold Trap (can we get it without the hard pipe?)

-2x 29/42 female to female adapter (recommended to have an extra)

-1x 29/42 to kf-25 ptfe adapter

-1x stainless 3-way adapter

-1x 29/42 to kf-25 adapter

-1x. short bellows hose
not found

-2x 34/45 ptfe kf-25 adapter (untested personally, stainless steel works well but is more expensive)



Me carefull with the kf adapter in stainless steal iT might hurt your glass Some day for iT expand faster than glass



Your Biggest isseu is vacuum pump size
You Need a minimum of 16 cfm on a 5 liter
A vacuum controller is of little use in SPD



So k went to look at my pump and k realize I totally misspoke in my post. I have a Welch 1/3 hp rotary. On the website it says it only pulls .o9cfm at 60hz. If this is true, then it looks like my pump might be the biggest problem



IT s probably treu
Go and find yourself a big pump on the second hand market and take your vac gauge with You When buying Any thing below 100 microns Will do Maybe a few flushes and ready
Or buy a new one for an arm and a leg :cry:

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For sure, the stainless steel only ever goes into the cold traps, never anything being heated. PTFE is preferred

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