I’m looking to peice together a 2 liter spd setup and I’m trying to figure out the correct vacuum pump. Is there a formula or calculations I could use in determining what cfm pump I need? Also I obviously read up on this before posting and from what I understand you want a pump that pull at least 30 microns for spd. Based on this would this pump work for what I’m trying to achieve? I’m honestly am just looking for the most economical option. Please lmk if you have any suggestions of pumps or anything like that!! t
Check these out
Pfeiffer Vacuum F-74009 Adixen Pascal 2021i Pump Red
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Welch 1400 series
Trivac leybold 2.5d
Alcatel 2021i like mentioned above
Edwards
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I’m going for an edwards edm 18 myself. Same specs as the alcatel. Those hvac pumps are not sufficient. My buddy uses a welch 1400, but there’s better for the price. Used on ebay under 500 and get a rebuild kit to go with it. You’ll be golden.
OP may not even need to buy a rebuild kit at first, my alcatel 2021i I scored for $399 pulled below 10 micron when I bough it. I just did a kerosene flush followed by an oil change that @Soxhlet recommended.
It sounds like hes on a tight budget and if he does end up lucky enough to get an alcatel that wasnt too badly abused like mine then his money would probably serve him better if he got a vacuum guage before a rebuild kit for his pump.
Edit: I got my pump from that same ebay listing @blackie shared.
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When you say the trivac leybold 2.5d. is that the same as d2.5e?
Like that one?
I’m doing a little bargain shopping myself trying to find a nice pump to get started. My closed loop pump won’t cut it for this.
There’s some good deals on those leybold and alcatels on eBay right now. Would you guys prefer one over the other?
Thanks!
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Just bought one. Even with $70 shipping it is still 1/4 the cost of a new one.
What a terrific upgrade from my blue & white R2-D2 pumps.
I couldn’t not buy one. Great find, bro!
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I second this, my alcatel pulled below 10 micron as well after a couple flushes straight from the same ebay listing.
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Need to hear more about flushes please.
Oh, and just when that couldn’t get any better, blackie is local to me. 
Starting to figure out he is a good resource.
All the info I have came from this website. Lots of people here recommended a used Alcatel as a budget pump. The one I bought shipped from Massachusetts. I was almost going to ask if I could pick it up to save on shipping, but didn’t. It was one of the best packing jobs I’ve seen in a while. Expanding foam inside of plastic grocery bags, so it would have been almost impossible to damage during shipping.
Also lots of user info posted. This thread has flushing info
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Yes, that’s the one I currently have. I have a rebuilt 2021i incoming as well.
I pull -80 microns with thebtrivac during my runs. No rebuild, was an MIT used pump.
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I just bought some of this because I don’t want to put kerosene through my beautiful babies.
I also have an Agilent MS40+. We call it ‘The Beast’.
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I can say without a doubt from experience selling pump you may want to avoid using this.
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Oh crap, I just pulled the paypal trigger.
Why is it bad Sensei?
So most people don’t know but several chemicals and reactionary processes are used to refine oil. Most of the time it’s handled like radioactive refinement. Where each process sends to another and it’s not about being continuous but rather stepped temperature and process. In the end i19 vacuum oil ends up being stable at or below 1 micron at 350-370c. What this means is it has been through various forms and stages.
Flushing fluid is just a cheap oil about 20-50x less in value and from what I’ve heard is about ten or more steps away from being i19. In fact ff is a biproduct of that 10th prior step(I believe) where the last stage in fracking the oil leaves two products. A slightly residual and less stable but lower purity discharge of the opposing wanted collection side where that oil is then further refined to the other forms of vacuum oil.
The contents of ff is leas effective in the following steps of refinement to useable vacuum oil. Basically people are just buying trash.
There is a method to clean pumps and this should be done with regular oil and is alot better than using ff. I’m happy to share the process but I hate doing it becusee alot of peering eyes are watching. Here I’ll ruin some people’s day.
Problematic pumps only to avoid a rebuild when contaminated.
Fill with fresh oil.
Turn on under vac for 30 min.
Open drain and flush oil.
Leave pump tilted with rag on drain when it’s all empty and hold in place rag to prevent shooting oil across room.
Tilt pump into trash can.
Turn on pump and free ballast the hardware spinning for about five seconds - durring that time slowly pour oil down the throat and allow the violent effect to shoot the vanes clear and rocket oil out the drain port unit trash.
Repeat about two or three times max.
If done wrong this can cause damage.
If done right this avoids rebuilds.
Make sure pump is hot when doing this.
It works better than ff, and to be honest i19 is marginally more expensive but whatever I don’t like putting garbage in my tools.
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Kinda like a forced flush like the welch manual reccomend.
Can used pumps bought on eBay be contaminated to where we should not use them. I was warned of this just wondering how true it is
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I also bought my 2021i from this same posting. After 3 hot oil changes I got down to 1-2 micron. Best money I’ve ever spent. If you want I have a welch 1400b that’s almost new I’ll sell for 1600.
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Yes and used pumps have toxic chemicals in them from process stations usually. Sellers lie everytime to make a sale and you’ll never know. Maybe they don’t even know what was in it.
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@spdking will multiple flushes clean contaminates from pump (Alcatel 2021i) or is the pump no longer good for our use.just to clarify contaminates in the pump will go into the oil and exhaust into the atmosphere.will this also contaminate distillate? I understand that both are bad and don’t want to do either.
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