Stainless Steel Rotovap? /OpenSource Idea?

Best bet is to find one of the rotary couplings on ebay with no glass. They come up for cheap pretty often because people break the glassware and the glass gets sold as part-out. Also a lot of time industrial salvage companies doing take outs don’t realize the glass is expensive and they’ll just sell the rotary couplings. Would not recommend trying to DIY one, totally not worth it

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Electric stir bars? Why don’t we use these for spd?

US $527.80 20%OFF | Laboratory mixing reflux distillation unit 250ml/500ml/1000ml/2000ml
https://a.aliexpress.com/_mKkr1UO

I mean just the motor and stir bar

What sort of vac do you imagine that seal will hold?!?

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That one? 150k microns if you’re lucky.

We’ve drawn up some in-house designs for things trying to do the same job, and one just came back from the fabricator yesterday. When I get a chance to put a vac gauge on it I’ll let yall know how well it works.

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That was my point…

@GroovyOctopusLabs: It’s not that the idea is horrible, just that implementation is non-trivial. It greater the required pressure differential, the harder the task becomes (presumably, not a problem I’ve looked at hard).

…and this implementation doesn’t look like they tried very hard…so the probability of reaching cannabinoid distillation vacuum levels are essentially zero (over sizing your vacuum pump by an order of magnitude might work)

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Mag drive!!

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Are they trying to copy this rotary seal design from a (dirty) reactor?



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You’d need a badass magnet as when they get hot they loose magnetism

Salem labs wiped film use magnetic couplings and when the magnets get hot you can’t get the basket over 150 rpm without it slipping

I’m sure you can do it you just need it done right, and there wipers are made in China so I know it can be done better

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Magnetic sealed bearings are rated for full vacuum as they are sealed and isolated so there’s no chance of any vacuum leak. They are very expensive 2-3k and can hold for a moderate amount of torque.
There’s other friction bearings that are cheaper and hold good vacuum. Not quite enough for short path though

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I wish I knew where to find a motor and stir bar like that for stupid cheap

Have you never heard of an overhead stirrer?

Missing why this is a novel concept to you.

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Im not to familiar with motors but would a concrete mixer style work seems similar to what you are trying to achieve.

Ik what an overhead stirrer is and a magnetic stirrer is. I just can never seem to find just the motors and stir bars without some kind of stupid glass set-up attached to it.

Just like the fucking wipers and the motors for wfe’s. Like why the fuck does it always seem like an impossible task trying to find one.

:octopus::expressionless::pensive: Sorry I got a little agitated there.

Retracted. AliExpress parallel universe me for the past several. Years and never showed me stir bars even though I searched so. Many different t terms… Same with Google… And DuckDuckGo… All of them
… What the… Fuck… Is… Going…
ON!!!

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Yeah you would need a mechanical seal inside the unit to keep the hot vapor away from the magnet for sure. As long ast the shaft was long enough and the coupling was a good 10" away from the vapor path I think you could keep it adequately cool but yes, not a standard design part

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Mag drive is great, but also not inexpensive and a bit fiddly. Samarium Cobalt magnets have super high temp capability but are kindof a bitch to work with from what I understand - they’re very brittle.

I’m hoping my newest design works as well as it should on paper. With any luck it will get us to “good enough for rough work” on the new system.

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TRAIN CONTROLLERS FOR THE SPEED AND ROTATION!!! bwahahahhahahaahaha

Led me to these