Been doin' some serious Brain Lernin' here (
@NickDlow ;-) and I sure appreciate all the great info in this thread.
Some questions:
High altitude:
@Bouldorado or anyone living at high altitude and using pump purge: As Boulderado mentioned, air pumps (compressors or pressure delta - aka 'vacuum' pumps) just like engines lose a lot as altitude goes up. [it's why I drive a "pressure cooked" car up here]. 1" HG per 1000 is probably in the ballpark for vac pumping losses as already stated by Boulderado. I live at 7500 so:
Is a 2 stage 'vacuum' pump required or highly recommended at this sort of altitude? Are these true 2 piston (large piston/small piston or large rotor/small rotor) 2 stage pumps or are they just referencing twin sets of reed valve box asys? For small batches, is cfm rating an issue at very high altitude or is that more of a time/convenience thing for reaching max possible pressure delta?
Aside: In physics, we're taught that nature abhors a vacuum. I know this for a fact since my Hoover Wind Tunnel is constantly on the fritz and I live out in the sticks or in nature... so...
Back to seriously:
Thermos w/QWET, etc?:
Thermos for QWET/QWISO/LWET??: I saw that there is a thermos method for blasting BHO and that got me thinking: While freezing separate materials for QWISO, QWET or LWET (solvent, strainer, etc): Why not freeze a thermos at the same time... the thermal deflection of the thermos seems like it should allow a significantly longer wash time safely without thawing water solubles like chlorophyll... no? IOW, freeze the weed in the thermos. 24 or 48 hours later (longer freeze due to TD), pour the cold EC190 or KX or ISO into the thermos... due to beneficial thermal deflection of the thermos, longer agitation time is safe without thawing the water solubles like the Chloro.
I'm a lazy bastard, so I was just wondering if this might increase yield and/or get it down to a one pass solution (double entendere entirely intentional).
If yes, then as NickDlow suggests, it would then probably be even more important to swirl the solvent/material mix gently versus hard shaking since the glass sleeve in most Thermos are pretty delicate and easy to break.
The downside to the Thermos idea may be this?: If'n I let it warm even a bit too much, it would take hours or more to remove the excess BTU's due to then-NON-beneficial thermal deflection, so the mix would then be sat'd with Chloro and a botched batch.
So I'm not saying go from 20 secs for ISO to 10 minutes or anything... just maybe extend it to a minute or something?? Then cold strain or in my case, frozen Aeropress.
I'm a newb so there is probably some clear reason why this isn't done. Just askin'.
I could blast outdoors all day long as my nearest neighbor is wayinthefuck away (like over a quarter mile) but it is so danged dry here, I'd be 'askirt' even with a ground strap due to a lot of static spark problems here. And just like the last time I fried a hard drive, it never happens when you're expecting it - much less, never when I'm near a Halon fire extinguisher!
I did a run of GD last month with EC190; got too much chloro in it but due to this thread, I darn sure know why! Even so, it was good enough so my brain was properly cooked a few times. Again seriously, it worked miracles for my asthma and allergies!
Ok, 15 pages more to go... back to larnin'..
Thanks again,
M