Anyone here ever take “the ebay challenge” on a used turbo molecular or Diffusion pump? turbo pumps and controllers for under a grand I know the 705 diffusion fluid is like 600 a gallon lmao just great…
those water cooled turbo pumps looking like a viable option for not 5000 and a great vacuum level. Do the diffusion pumps really catch on fire if you expose them to atmospheric pressure with no cooling still trying to figure out if its a possibility for me to employ one in my setup
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Not on those. I have scooped edwards and some super cheap diaphragm pumps! Take a chance. If it looks new ish it most likely is.
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Im not going into details but i’m just going to say I have 2 buchi r200’s both look NEW! not sure how many parts work on the one lmao but yeah one is great 
I have def had some good luck on used equip but you can’t win em all
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Almost every pump I own (diaphragm, diff, rotary) I bought on Ebay and generally look to source most things used if I can. My experience is to vet the seller and ask questions before buying. I’ve been burned from Ebay before, but very few compared to the gems.
If you want to buy lab equipment on Ebay, pharma and biotech companies fold and or upgrade all the time. It definitely helps to know how to service the equipment you buy incase it needs a tune up
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I have an Edwards diffstack diff pump that I still haven’t fired up but It came in grgeat condition- if you wanna see it lmk I don’t think I’ll be using it anytime soon
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totally interested and i am not far away you looking to sell? i was thinking go diffusion but not sure if cost of running it and feeding it diffusion pump oil is an economical option vs the turbo molecular? still trying to look into been busy af
From my research, diffusions are probably what you want in a short path, turbos sound sketchy. I’m in th same boat as Rowan, I bought one In good condition just need to get the heater part wired up
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Turbo molecular pumps work fine with cannabis distillation offering a significantly smaller footprint and no expensive oils to ruin, however they need a very strong trap system in front, LN2 strongly recommended. We had one on a WFE for 3 years without incident.
That being said, it would probably be cheaper in the end to get a used diffusion pump
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thanks bud that sounds like about what i was thinking if i can get the extra cash i def might try the 300 ebay challenge on a turbo and LN2 setup and controller, where can i find a good metal cold trap for the liquid n2 that’s not a thousand dollars lol. its not that bad going liquid n2 is it i seen cheap enough storage kegs i might have to go far to get it though hard and far just for fkn dry ice lolz hard living in the sticks
thanks bud hellz to the yeAh @Killa12345 i just built a bi-directional closed loop trying to figure out how to filter older material just ordered a 5 micron sintered disk kit for 1.5 " tri clamp hoping that will help my filtration got the filter disc and ring kit too my first run with a bunch of older trim through 3 coffee filters did not do well color wise even with a frozen 3 foot jacketed column
Low cost steel cold trap? That’s probably another Ebay find. I’ve used LN2 with glass traps just fine, but obviously extra precautions need to be taken.
LN2 is no fuckin joke, ALL precautions should ALWAYS be taken with it. But it is an incredibly useful cryo fluid. Usually the pumps I put it in front of rarely need oil changes as the LN2 will trap most volatiles (at least all the terps and solvents I’ve thrown at it), the only time I have an issue is if a tech or I forget to replenish the supply in the trap
If you’re going to get a turbo make sure you have a dialogue going with the seller before buying. Ask a lot of questions. It is way easier to fix and rewire the electronics on a diff boiler than it is to find compatible controllers for a turbo, at least in my experience.
I’ve had the best luck getting turbos/diff that were pulled from working mass specs, they were usually exposed to cleaner environments and better maintained than distillation systems and other high vac applications
Good luck
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Also the deepest dry vac I pulled on a stainless WFE with turbo was 3.8 e-5 torr, deepest running vac was around 1.5 e-4 torr. Just for referenc.
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yeah was def looking at the pulls from working environments and def agree with the mass spec units for clean units thanks for your time and input bud appreciate it!
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Diffusion pumps, as long as all parts are there are fine from ebay. There are no moving parts so as long as the stack is still there you should be fine. Also, if you take care of your diffusion pump (multiple cold traps and vlaves to isolate the diffuiopn pump incase of a worst-case scenario) you shouldn’t have to change that expensive oil hardly ever. Protect your diff pump with multiple cold traps.
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