You should go up to 140-150c to degas completely when you decarb. It will remove a massive chunk of what you’re removing in the spd.
Also start using bellows instead of gl connections and hoses. It will make your life easier once you’ve mastered that.
Edit: lol @tetramethylsilane . Great minds think alike and apparently type at the same time.
Haha.
Yeah definitely upgrade to full bore (kf25 bellows) ASAP. I suffered thru a GL18 2L for half a year before upgrading to a pretty sweet full bore set up and damn does the wider vapor path make a world of a difference. In terms of run time and vac depth.
You can probably upgrade for cheaper than you think too. If you post a pic of your set up, we can get you squared away.
Oh wow that high! Done. I appreciate the decarb info!
I almost did upgrade but I have this crude so I figured I’d run this through then upgrade for the next batch I make. Here’s a pic of my current setup.
Ok. So, that heating mantle is not ideal. I used that style in university, so figured it would work for our purposes, but I got much better performance from the standard heating mantle/stirrers you see used in our industry. Makes sense because more of the flask is in contact with those style mantes than the one you got. Also better temp control than with a variac. Combine it with a top mantle and you’re golden.
So that said, it will cost a bit more to upgrade your set up then I had thought.
For mantle, you’re gonna want something like this (just using USA labs as an example)
USA Lab 2L Digital Heating Mantle W/ Heating Top - 300°C 3000RPM USA-HM-2L - USA Lab $1,199
You can use the same boiling flask and condenser and couple it with an isolation valve:
Isolation Shutoff Valve - Rocco Scientific | Laboratory Glassware $400
You could also go the swing arm route (both methods have their advantages and disadvantages)
Dual Swing Adapter - Rocco Scientific | Laboratory Glassware ~$150
Kf 25 cold trap (I recommend using 2) 1L 3 Port KF-25 Stainless Steel Cold Trap – Quality Stainless Parts $300 each
And then say another ~$300-500 for the bellows hose, right angel valve, random fittings and what not.
Yeah I used those types of heating mantles in college so figured it would be okay. I have a 5 liter heating mantle stir bar combo (pictured) but I just don’t do runs that big so it sits on the shelf.
Thanks for those links that saves me a TON of time trying to hunt them down. I really appreciate it 
Ok, I’m pretty sure i can see your issue of this is the exact way your running it. Now i could be wrong, but the hose coming off the cow doesn’t have a hose clamp on it and is also excessively long (imho). Once you build pressure on your system there is nothing holding it in without the hose clamp and that would fuck your run up indeed. Cut that hose to 5 inches or as short as you can get it to connect to the cold trap and still be spun.
Until you get bellows I’d take off all gl connections and run the hose directly over the threads, that made my vac go down and stay steady for days before i got thr fullbore setup. Just be gentle when you put the hose clamps on. DO NOT OVERTIGHTEN!
And this is the first time I’ve seen anyone use a mag stirrer as a heating mantle.
I actually have the vacuum hose running from my cow, to my vacuum gauge, then on to the cold trap. Is that the correct order? But okay I’ll shorten that hose up!
And the mag stir plate is only being used for the stirring function and thermometer. I have a glass col fabric heating mantle sitting on top of it connected to a variac that’s actually providing the heat.
I’m not going to go into the American vs Chinese glass rant too far, but if you don’t have a lot of experience in buying and validating the quality of lab equipment then don’t buy the rock bottom cheapest priced stuff you can find. You are posting on here to fix problems that are caused by you not investing in better quality equipment. Now everyone is jumping through hoops trying to help you find your problems that should not have been there to start. You are performing a high vacuum, high temperature distillation wit scalding hot oil inside that could implode at any time. Take it more seriously.
Start by replacing your stopcock valve on the boiling flask. Those aren’t rated for even moderate vacuum. You need oring piston type valves like here
Check your thermocouple adapters. For the top one in the head use this one here
Replace your gl connectors. Those are polypropylene and the terpenes will dissolve them. You need PFA ones like here
Let’s start with your pump…
The pump should be under 10 microns blanked off and reality under 7 microns. Seems like you need an oil change at minimum.
Second your vacuum hose from cold trap to spd is crazy long and needs to be shortened
You should be under 100 micron on a dry system no oil. I think 500 microns is not an ideal starting point.
It don’t sound like your cleaning your crude up good enough before starting. There are threads here to lle the terps out and proper Decarbing techniques.
I’ve pretty much had all these problems starting out. Work from the pump to the system and figure out where you leaks are and fix your pump and hosing correctly.
no sir
because I’m a nice guy I leave it to others to tell you where to actually put your vacuum gauge 
see: Need advice on where to put digital vacuum gauge on my SPD system
edit: and what’s with the box you’re squeezing this into? that it NOT going to help you get this right. although @goldleaf_scientific is correct there are serious risks here.
I’m assuming you’re distilling crude, is that correct? Crude is usually a majority THCa which begins decarboxylation around 110C and lasts until around 130C if you go quickly in a short path. You can expect vacuum levels to rise during that time. Prior to hitting 100C it’s not uncommon to have volatiles and terpenes causing the vacuum to be anywhere from 300-600micron.
Up to that point everything you’ve described is normal. Your issue is that you’re using your nice deep vacuum during this portion without protecting it well enough. The volatiles up to 100C may effect the pump but when you add a carrier gas CO2 from decarboxylation, a ton of gunk can end up in your pump.
That gunk will likely stay there in your pump oil because it would normally have condensed in the trap, if there wasn’t a CO2 carrier present. That means the stuff isn’t “that volatile” relative to something like a solvent which can vaporize out of your pump oil pretty easily.
The lesson is to decarb with at a minimum a different vacuum pump than the vacuum pump you want to use for mains. Happy to help further if this sounds like it’s on the right track
I have a super simple way to decarb and final purge etoh out.
Dump rootball crude into spd bf
Place on mantle (open, not sealed and NO vac)
Put thermoprobe in crude
Set spin bar to 1000 (1400 if possible)
Set temp to 40c
Keep slowly ramping up temp (80-85c max) and let it run until the crude is smooth as a lake even when stir bar is running). Let run like this for 20 mins at 1400rpm spin bar.
Now your fully decarbd and purged and ready for spd.
This is my SOP for my runs. Easy peasy.
To be honest the reason why I wasn’t able to get below 20 micron blanked off was probably because of my crappy vacuum gauge.
As far as my adixen 2021i is concerned, I bought a used one that had gaskets etc. replaced and an oil change, so we should be good to go on that front.
So I heeded everyone’s advice and did away with the gl 18 connections. I hooked my vacuum hose right on to my cold trap and clamped. I also re-checked all connections and cut 5 feet off my vacuum hose. I just tested on a dry system and was able to pull 95 micron and dropping after about 25 minutes which I’m ecstatic about! 
I’m going to give her another go after dinner and I’ll check back with my results. Hopefully it’s a success!
Update I’m new so they wouldn’t let me respond again until now. Just finished my run. HUGE success! Pulled sub 200 micron on the main body. I couldn’t be happier! 
Thanks so much to all of you that chimed in to get me there. MUCH appreciated!
Thanks for this great info! I have a trash pump I can use for heads. I’ll definitely be doing that in the future.
Thanks for this! I’ll give her a go next time around.
I ended up placing it between the pump and the cold trap. Worked well. Hopefully the cold trap will keep it from gunking up so quickly. 
Nice. I’m glad we could help you out. The more you get into this the easier it gets. We are here to help you in any way we can.
The box is a DIY fume hood that exhausts out the top and out the window. Built with inch thick MDF hardboard. The front is made with half inch thick plexiglass so if the “Chinese glass” were to “implode” as it were, I’d be just fine minus a hurt pocket book and ego lol
An extra safety net for now as I slowly upgrade my system.
It also completely contains the smell which is great!
