What is this connection? It looks like the KF fitting has NPT threads and you have a JIC screwed into it. It’s normal to lose vacuum if you turn the pump off unless you have a valve (it’ll pull air back through the exhaust)
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Yes exactly, its a KF fitting with 1/4 NPT threads so I had to get a fitting that would convert to 1/4 Flare so I could connect the vac gauge to it. Thanks for letting me know that loosing vacuum is normal it had me a bit worried.
The max vacuum im getting on the gauge is 50 microns, could I do an spd run at this level ??
If this is a used vacuum without flushing, it may be worth opening the off-gas valve and letting the pump run closed off for an hour or 2 to bring it up to temp. There may be residual solvents in the pump oil that would prevent deep vacuum. Those threads are probably leaking but I would imagine you still get closer to ultimate vacuum than 50-60 microns. Also, if you need to test with those threaded connections, make sure to use tape. You can run at 50-60 microns when plumbed to your glass but I imagine your vacuum is going to be much higher unless you have good glass.
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if you’ve got some distillate, seal up your threads with it
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Thanks man, when you say I should use tape you mean teflon tape on the threads of the fittings ?? And about the off-gas valve you mean the gas ballast ?? just leave it fully open during 1-2 hours ?
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I don’t have any disty yet but I got some apiezon 501 vac grease, would that do the job ?
It should do er, Ive even used nylog before to chase vac leaks(not for use during production runs).
Yes and yes! Sorry, been a long day; my nomenclature is off but that is what I meant.
Excellent bro, thanks a lot 
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Perfect, Ill give it a shot, do you think I could also apply the vac grease to the fitting where de vac gauge sensor screws into ?
For safety and since I don’t know the condition of all of this; just be sure to check the temp of the pump every once in a while. I would hate for it to overheat and sieze on you if oil was low or too many contaminants. You more than likely wont have an issue but I like to be ready.
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do one spot at a time if you want to know the exact spot/connection.
ive put some grease on my gauge connection threads/flare before, just use very little, I apply it with a toothpick
Ok very well, ill attach a thermometer to it while I do this run, what’s the max temp I should allow ??
Just to clarify so I don’t fuck things up, you mean run the pump for 1-2 hours with the gas ballast completely open like in the picture ?
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there’s not many spots to try, I got the vac gauge connected directly to the pumps inlet port, all there is between the pump and the vac gauge is 1 KF25 fitting and a flare reduction that’s all, only 2 fittings plus the vac gauge
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I’m not completely familiar with the e2m8 but I know on other larger edwards the valve stops before you can fully remove it. Keep it capped on there but open and that should work. I would be nervous about sucking in something large with it fully uncapped like that. You may have to quickly google the e2m8 manual to be sure.
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I got the manual right here, alright very well I think I get it now, will give this a shot
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I did what you suggested just finished the 2 hour run but had no different results, the hottest it got during the 2 hours was 45 degrees Celsius. The sound the pump made was intermittent, for a while it was steady and every 5-10 minutes or so is sounded like some sort of bubbling and then it went back at a steady sound, I had the gauge blanked off for the whole process and the lowest it got was 45 microns.
I just hooked it up to my rotovap to see how far down it would go and the lowest it gets is 200 microns, any suggestions on what I could do next ?
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Hook it up to your empty or cold spd and see what you can pull down to.
I also can only hit 45 micron with my pump and setup, the higher the microns the higher the heat needed, 45 - 100 is a okay.
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@Capttripppp @GroovyOctopusLabs @Demontrich @SidViscous @HeisenbergInd
Time for some Thursday night Trivia! Im really sorry I have to summon y’all again but I’ve been having this problem since yesterday and im slowly getting there but I need a final push to reach the solution to my problem.
As you can see in the pictures I got the gauge blanked off at the pump and the lowest it gets is 60 microns, right now the lowest im able to get is 45 microns but that’s it, not a micron more.
At the inlet port I got a KF25 1/4 NPT fitting, then a female 1/4 NPT to 1/4 Flare and that goes into the vac gauge.
I applied some apiezion 501 vac grease inside the female 1/4 NPT (This is very important to notice, I applied it INSIDE) and as you can see on the third picture pretty much all of it is outside, so that definitely tells me I got a leak there, right ??
All I want to know is what’s the best way to get rid of that leak, I tried 2 different teflon tapes and have the same result.
@pangea just told me as I write this that 45 microns is not that bad after all, so thanks for that it really relaxed me, but I would really like to hit full vac
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naw, its leaks out from compressing when tightening, leaks with vacuum suck inwards, but can easily be imperceptible.
The gauge could very well be the issue. Most dont trust cheaper hvac oriented gauges.
What does the gasket in your brass adapter look like?
You can seal connections after they are threaded and connected by applying grease around the outside of the connection, so if its driving you nuts you can slather up everywhere and see if it makes a difference as the pump is running.
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