Slow pull speeds on SPD

Currently my SPD has only yielded me half a 250g collection flask over a 9 hour pull period. I’ve been collecting body for 4.5 hours at a steady mantle temp between 200 and 205. My head temp has been between 180-182. This is all at between 160 and 210 microns. But my collection has ranged from a speedy swirl to painstakingly slow drips most times . Any recommendations for improved pulling? My goal is 500 mg per day. I can’t imagine it happening at my current rate.

Thanks guys

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What speed is your stir bar?

Turn your lights low and run a flashlight over the joints to see if you have a leak, doesn’t look like it, though.

How often do you change your pump oil?
And what pump?

What temp is the condenser?

Or you could have a leak after your short path and it could not be pulling hard enough on your still


Pls tell me which volume for heating mantle and the rotate speed, because these two points is important to pulling.

I am manager terry from China manufacturer that has been specializing in producbig rotovap, chiller, spd, molecular distillation and so on.

And if you want to have the quotation, I could provide it with u.

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I do not believe it is a leak because my vacuum gauge reads stable. I have a bullseye.

My condenser is a steady 50.3

I just got my pump used and changed the oil three weeks ago. It is an Alcatel 2021i and I’ve been pumping steadily between 160 and 200 microns.

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As for stir bar speed, my mantle does not have measured control only a throttle. I sometimes wonder if it’s moving steadily on top of the heating glass beads. Is there a way to ensure my round bottom stir bar is moving properly?

Volume is 2000 ml spd loaded with 560 g material.

The stir bar does not have digital control. I have a steady reaction now but cannot be sure if stir bar is doing its job.

Raise you condenser temp to 80


Take the beads out. They don’t work in conjunction with the stir bar. They are probably what’s causing this issue.

And you can put more in there. 1L to 1200L would be ideal. She doesn’t run as efficient empty vs full


And yes raise your condenser.

Your stir bar should be able to get to 1k rpm or within. More than half of what that mantles dial


My current issue is a lack of Pyrex to winterize the necessary shatter . I’m also waiting on more ethanol, it’s been expensive to source. Th winterizarion process is slow because I’m not using a Cryo freezer

Nearly 12 hours of run on 560 and this is the result. Will try again tomorrow without beads and increwased condenser head temp.

You might want to get a larger stir bar with more weight behind it.


My current one is 40x20.

Also, since I seemingly need to run more material, how would I rerun my tails being that small. I’m assuming that’s around 100 grams, way too little for a run?

Wait to do another first pass and join em together. When you were getting to the bottom of the flask, what was the stir bar doing? How well was she spinning?

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Get a heavy stir bar since you don’t have a rpm control that way it displaces more oil, and maybe some fire rope to insulate better, I’ve always noticed the faster I can run the magnetic stir bar it translates with quicker distillations.

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Change your pump oil each run. Every time

Use flushing fluid and then fill. Run hot, repeat. Then every run replace after first pass. Second pass will like the fresh oil, and it can handle first pass for next use.

Get grade 19 from vacoil
And they also have flushing fluid.


Looks like she’s not even moving and got caught under the beads.

Patting myself on the back.


The beads are the devil. Take them out next run and you will enjoy doing this.