If you make it pull enough it should be able to go through this walls and glass
As long as there is some air left I there the sound should be able to travel
I spoke with @Sidco_Cat about this at CannaCon in Seattle around 2016, completely changed the way I purge. After introducing backfill procedures I was easily able to obtain 0ppm readings for all hydrocarbons between 36-48 hours oven time. Nitrogen also dramatically reduces the amount of nucleation we saw in shatter because all of that ambient relative moisture and oxidation no longer happen every-time you break vacuum to do flips or maintenance.
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Had never heard of using N2 as a suppressant for nucleation, but that does make sense. A lot of people use n2 to blast through their material columns before running to help remove any excess moisture.
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Its the only way. I waste a little nitrogen at first so i dont have babysit the muffins and it is the the only way I have been able to get consistent glassy slabs.
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It’s not so much that it suppresses nucleation as it is actually mitigating a couple factors which do facilitate nucleation. When you use atmosphere to neutralize vacuum you introduce tiny particles, water and oxygen all of which degrade your concentrates and can be yet another starting point for nucleation.
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Yes pardon my wording that is exactly what i was trying to say haha.
I just need an oven that can handle back flow pressure ughhhhhhhhhh
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Cascades and Across international both perform wonderfully with nitrogen sweeping. And I’ve seen the cascade ovens used as large pressure vessels for “mining diamonds”. Though I’m not certain they’re designed for it…can you clarify that @Sidco_Cat
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Proceed with caution any time you are using a vacuum vessel for a pressure vessel or vice versa. The spring-loaded window acts as a pressure release above 2 PSI.
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That’s my girl!
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Ive read a lot of issues with peoples door seals popping off or outward. So you guys are really only backfilling with like 5-15psi?
When I backfill it’s much more like a sweep. I never build any pressure with my nitrogen. I simply neutralize the vacuum with nitrogen. Even when actively sweeping with nitrogen to speed up solvent and moisture removal you don’t build any pressure, you simply flow through system. Just about Any pump you hook up to a vac oven is going to pull significantly faster than the 1-5 psi we like to use when purging. Hope that makes sense.
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What kind of safety precautions are necessary for using the nitrogen backfill since N2 is an oxygen displacer? Does it have to be as ventilated as a room for butane (obviously not), but looking for sound advice so i can impliment this in my lab. Is an O2 sensor necessary?
Are you venting the pump on your vacuum oven directly into the room?
Stop doing that, and the extra N2 should be fine…
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You get much better heat transfer in an oven filled with inert gas compared to a vacuum where the heat transfer is due to radiation only.
I typically backfill with Ar because I have a cylinder for my TIG welder but most folks use dry N2.
I think CO2 would work well from a heat transfer perspective and it is really cheap. thanks to the paintball fanatics.
I pull and purge a couple of times because the purge connection on my oven does not create crossflow.
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Whats the typical size tank of N2 to get and how long would it last. Typically I’d run (4) .9cf vac ovens and fill each oven 1-2 times a week depending on what i have to extract. just looking for ballpark of how long it would last.
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Love this thread! What valuable info.
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