50L Lab1st Rotovap vs 5 Gallon Rainier Distillers Weed Witch

I’m looking to switch to ethanol extraction and I’m having a hard time deciding between these two options for ethanol recovery.

They are both in the same price range ($10k) so I guess it comes down to which would recovery more in a day and ease of use.

I would love to get your guys opinions on this and pro/cons to both options.

Here’s links to both:



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I only briefly read the description for the weed witch, but it seems ridiculously overpriced for what it is. You can get essentially the same setup for about 1/5th the price, or build one for 1/10th. There are red flags everywhere with their marketing. The claim that you can produce 200-proof ethanol being one of them. Sounds like another company selling well established technology at an insane markup just because it’s marketed to the cannabis industry. It doesn’t even look like you can put this thing under vacuum… :roll_eyes:

  1. Distilling your own alcohol is not legal.

They will tell you to get a fuel permit, but to be legal, you need to apply for that through the AFT. Then, once you do that, to be legal, you need to denture the alcohol before use.

Also, are you looking at it for extraction or alcohol recovery. I have trouble understanding how the weed witch could out perform a roto.

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I am purchasing ethanol denatured with heptane for extraction, not planning on distilling my own ethanol.

I’m just trying to figure out my best option for ethanol recovery, I’ve been leaning towards the 50l rotovap as I’ve been pretty happy so far with the 5l I got from the same company. My only concern is another thread recently posted where someone was having an issue with the vacuum seal on their 50l.

Edit- This is the thread that concerned me about this Chinese 50l rotovap:

I don’t know your process or how much ethanol we’re talking, but It seems like it would be cheaper (probably much faster as well) to build a vacuum still for recovering the bulk of the ethanol, then finish it up in a smaller roto like your 5-liter. @Roguelab is working on one shown in this thread that looks like it would serve your needs.

You might also find this thread useful.

There’s also a few threads about falling film evaporators, but those might be beyond your budget. You could probably get away with building/buying a still that isn’t under vacuum as well (much cheaper), but you might run into problems exposing your extract to that amount of heat for an extended period like that. Unless you don’t mind that. Just make sure you choose a heating method that isn’t direct flame or even an internal heating element. That’s one safety issue that stood out to me with the “weed witch”. It looked like they’re heating the boiler with an element that’s inserted into that bung hole. If that’s the case, I’d constantly be worried about ignition when distilling such high-proof solvent.

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Hello there,

I am the individual who was having issues with their seal. I seem to have fixed the issue by introducing pfte gaskets that I cut from a sheet of ptfe. It you don’t leave the boiling flask full of product overnight then you shouldn’t run into this issue.

You shouldn’t have an issue getting 15L/hr with a 50L rotovap and the proper chiller. Overall, if you can get one at an affordable rate (<$10k for chiller and roto) then it’s worth it in my opinion. I will actually be buying a second set, even after running into this issue.

The machines themselves are simple and so problems that may arise will generally be easily fixed.


Thank you very much for the info. I was a little worried but feel much better about getting that 50l rotovap now. That’s a great output per hr of ethanol, even more than I expected.

Just to confirm you got the 50l Chinese rotovap from lab1st right?

I remember seeing you post in a thread back in April that you were ordering one. If so just curious how long did shipping take?

I took quite a while to receive my 5l rotovap and 2l distillation setup from them and noticed the shipping times on the eBay listing look even longer for the 50l so just trying to get an idea of what to expect.

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I ended up going with a different company. I deal with a middleman located in the states so it saves me a little headache dealing with the Chinese companies directly. With this company, shipping took 2-3 weeks.

Edit: Generally speaking, all of these Chinese rotovaps are built similarly and so quality is mostly similar. You WILL run into issues but nothing you can’t overcome. I had a coil blow out on me in the heating bath but that was easily replaced.


Hi buddy,

i am China manufacturer and my main products are rotovap, chiller, spd, vacuum pump and so on.
good price and quality.

If you need the quotation, just DM me and tell me your inquiry content, then i could send the quotation to you.

some people on this forum has purchased rotovap from me, like @tare @asher and so on;

welcome your inquiry.

Weed witch is bullshit they only have 1 5 gallon and 1 50 gallon. They have no capacity to produce more. Never deal with rainier distilleries. American Greed episode at its finest.

Ya the weed witch looks like a basic alcohol still u can get of alibaba…imo way better for recovering tons of etho (the cheep alibaba version ) u can just dump gallons of crud in there heat it up, this is good shed backyard tec …if u have a real lab u gotta buy a roto sorry lol

Pro tip spend 8k on a good roto with a lift motor for a reputable vendor and use a dry ice cold trap (I like chemglass 1 piece plastic coated for rotos ) and a cheeper vaccume pump

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