Looked pretty sweet
Dry pump, 0.022 torr. Seems pretty ideal for our world? Or would it just get destroyed by terps and the like?
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We use a multi-stage roots style pump and it runs great. To be fair it’s cold trapped up the wazoo but still no issues with it whatsoever. Ours is a bit bigger than that and it absolutely rips. I can run 6 vac ovens, a lyophilizer, 4 rotovaps and still have enough chooch to back a diffusion pump on the SPD at the same time.
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That sounds like a BADASS pump
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It sure is. Proper piping goes a long way too, all 2" stainless hard pipe, KF joints most places etc. Leaks eat up a ton of capacity on distributed vacuum systems and you’d be amazed how much outgassing adds up.
Probably have more in the piping than the pump. Bought it used off eBay and we liked it so much we bought a spare lol
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I’m such an eBay junky. I spend so much time just digging around looking for cool shit, mostly people just don’t know what they’re selling. Here’s a brick shithouse of a cryo cold trap that would probably pair nicely with 250mm diffusion pump:
https://www.ebay.com/itm/Cold-Trap-Gas-Processor/161522406637?hash=item259b7c54ed:g:3QEAAMXQh8NTdNyB
Maybe a little expensive, but I so badly want to hook it up to a 10l SPD and see how cold you can run some disty. Anyone ever pull deep enough vacuum to distill/sublimate THCa? (A diff pump is probably not sufficient for that but a turbo might be able to)
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That sounds cool. I just tried to calculate what kind of pressure would be necessary but my nomography seems incorrect, probably because I have neither a latent heat or normal boiling point for THCa. And my calculator says d9 should boil at 14 micron and 80C which it does not
Still, I can’t imagine you’d reach decarb temp to distill it at a decade or two below 1 micron
I about choked on the price!
First rule of eBay: smash that “make offer” button. You’re not wrong but a used 250mm diffstak runs about $5k and I wouldn’t consider it unreasonable to spend as much on traps as the pump and I bet that seller would consider it. I would consider it unreasonable to use that setup on anything other than a very large wiper though lol
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Not really an SOP. I ran some oil that still had roughly 40% THCa and about half of that didn’t decarb in the distillation. <25 mTorr at 125C
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Did it just stick to the walls of the glass?
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Huh?
No, it distilled. Acidic cannabinoids can be distilled without decarb in a wiped film. I just never took the trouble to make it efficient, if it even can be.
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Sorry I had assumed it would have crystallized and stuck to the glass during distillations; but that’s nifty af! I’d love to learn the process, as the acidic versions of cannabinoids would be a huge benefit for my crohns - I’ve seen the centrifuge thread for spinning out thca from etoh I believe using the little test tube thingys (I forget the name of them 
)
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