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Flash point of various oils
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To my novice experience… 267 degrees is way far beyond what you should be anywhere near. As for the vacuum, I have a cheap old shitty orange vacuum pump I use for my oven that pulls to -30hg. For my spd the cheapest functional pump was the welcho duoseal which was over 1000 bucks, along with a few hundred dollar vacuum gauge. My guess is your hardware is not sufficient. Def need a vacuum gauge.
What hardware did you change from your old 2l setup besides glass and mantle. How were you pulling and reading vacuum
Before? Maybe post a specific parts list and someone here can make a better suggestion. Good luck!
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Hmmmmm I do have lots of old oil laying around but yeah I’m not too sure if my chillers components would appreciate that. Not to mention my chiller only works from room temp to -10 degrees.
Anybody have experience using the poly science recirculator?
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It’s pretty easy to check the seal compatibility. I’m 95% sure you’re not gonna run into issues using your old pump oil but I haven’t bothered to do your Google work 
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Like I mentioned it wouldn’t really matter because my circulator doesn’t achieve the temps I need to do a run.
With that being said why would a chiller/circulator that can only do ambient temperature down to -10 degrees celsius be included in a short path distillation system? Does ANYONE ever run their system with cold fluid going through the condenser? I would imagine if the condenser was cold that the distillate would essentially just freeze and clog up the path way…Anyone have anything to say about this?
Are there certain compounds that require incredibly cold temperatures to condense?
When running my system I thought I noticed little specks in the air being pulled by the vacuum pump…
Im wondering if possibly the vacuum is pulling so hard and so fast that it is literally pulling distillate all the way through the system without giving it a chance to condense back into a solid… Just a thought. I dunno.
265 means you have a bad vacuum setup, bad mantle heat management, and leaks throughout. You can’t just ask what the problem is without noticing the three items that cause this issue. My telle is 408-348-7264 and I can hold your hand and walk you through it while you assemble and service your pump and short path to avoid this error. At those temps you may have damaged some material so doing a short bed silica 60 pull will remove the degraded compounds and allow your next distillation to opperate better.
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Is this a troll thread?
It seems like your doing everything wrong that u can.
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This thread is more than mildly concerning.
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Hey I have been having some trouble running my short path. Would you mind if I got some advice from you? over Telegram as well?
got my short path System from USAlabs and I set up in another country so it’s hard for me to get good product here but anyways they forgot my vacuum grease and I’ve been using this cheap silicone grease when the temperature hits 40c the vacuum starts dropping and the temperature starts dropping is this because of low quality vacuum grease?
Yes
If there is really no option there is heat resistant silicone 300C that you can use but
Don t forget it is a gleu do all joints must be swiveled every 6 hours if not it will get gleud stuck wich can only be released with a heat gun till 380C it can be released
It s used in the automotive industry and in the
Heating and refrigeration industry
And only the hot joints it should be used
I Do NOT recommend it thou
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I’ve use usalabs elcheapo vac grease with zero issues.
We use dow at work.
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@tweedledew do you actually add heat to your conderser?
If your head probe is at 160C what would “ambient” be in that general vicinity?
If you had no other heat losses (which unfortunately is not true), then that ambient to -10 chiller, set at 90C might actually get the job done.
Being able to set it to 0C doesn’t seem particularly useful, but actually having refrigeration might be.
The old standby is a bucket heater and an aquarium pump. The pump will melt if you don’t regulate the temp below 80C or so, but it will get the job done for less than $100 in parts.
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Do you have anything in the boiling flask at this point?
How has it been decarbed? Are you certain there is no solvent left in it?
You expect vacuum to drop when something starts boiling…
Boiling at 40C suggests residual solvent.
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I don’t add heat. I generally just run it open to atmosphere with oil/glycol and there’s enough heat lost through the air at the relatively low takeoff speeds on my 5L.
I did hook up a chiller to it that maxes out at 95c. I noticed more stink to the end product. So likely just gonna go back to just leaving the condenser head open to atmosphere but filled with fluid
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meaning you’re almost certainly running your condenser above 95C?
ever checked to see where it stabilizes?
had to put a fan on it?
it certainly looked to be doing the job just fine when I saw it last.
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Yah I switched to a full bore system finally. So I was a bit worried the faster flow was gonna give me issues.
I ended up putting in some interference in the column, so my takeoff rate isn’t that much more impressive. So I’ll likely just switch back to non circulating.
I think I got a reading around 120c when I tested it once. Probably worth figuring that out.
Throwing a fan on it seems pretty practical.
did you make it common knowledge how that was achieved?
as in you had a local glass blower amputate the GL-14’s and replace them with 24/40’s
Krytox seems alright