Can you tell me why some setups use a cow receiver and some use the valved vacuum adapter, like this: https://www.bestvaluevacs.com/valved-vacuum-adapter.html ?
I’m trying to overstand how the valved adapter is advantageous.
Thank you!
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I would only use those adapters if they were full bore back to the pump inlet. Not sure what the advantage is if it’s a gl fitting. My understanding is cow=GL fitting isolation adapter=full bore
Designing is a big word 
The advantage ofvalves is to isolate sections of You glaswear undervacuum
And the gl fittings arehandy for vacuum but also to Ad innert gasses or probes When nessesary
About designs i think the goodones are way over priced and several of the wide bore types are equal to ns45 in speed
I personally run 5 liter rigs or smaller
F or the market here is notthat big
I try to mold designs with a glass blower
To better them but none has up to now made a huge diffrance
I Am currently putting a simmilar setup toghther only with a brett cow making receiving fraqtions possible for i am currently Busy with CBN issolation as good as possible
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Many available on Ebay. The head that goes with it is neat but uses a 14/20 joint.
Go to Any glass blower to modify
Alot is possible even changing ns sizes
I have a China head that got modified beyond recognition 
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That would be great if you believe your mains will net more than what the volume of the flask can take.
Minus it not having a vacuum port
I Placed iT underneath the valved thing ( don t know how You call iT ) You have to find a female female adapter do
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I believe it goes first cow was being used to seperate the three main fractions . Then a mono cow as everyone not wanting cross contamination and mainly to improve vac levels by not having a secondary boil going on. Then the valve came that allowed monocow advantage without breaking vac and loosing time and causing oxidation. But not we are on the swing when talking about spd. Regardless I have found you need to be able to break vac and flow inert gas through to remove any potential secondary boiling
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When you go to switch receiving flasks, you close the valve leaving a vacuum in the boiling flask. Do you then have another valve or cap on the lower connection to allow for depressurization in the receiving flask?
I’m thinking of going with a mono cow. I really like the idea of getting the stinky heads fraction out of the system so it doesn’t mix with the main body.
Yes you close the main valve and can release pressure with the lower cap off to remove the recipient flask it helps with smell and better vacuum for me.
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Had a postal note on my door and my mono cow is their waiting for me to pick her up tomorrow. Cold trap with a 24/40 female joints follows closely behind 
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Where did you get your cap for the lower vacuum port??
Thanks for the detailed explanation! I get it now.
Used a gl fittings cap that i used silicone plug and epoxy to make a blank off cap
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