Here is a thread for the purpose of CIVIL discussion surrounding the most effective vacuum pumps to use for the purging of oil. Please keep the thread on topic, and as constructive/progressive as possible. If you have any inquiries or comments surrounding the discussion, please post them here as opposed to sending pm's so that everyone can gain the knowledge that is being sought after in this thread. After all, this is a progressing technique that no one person has all of the answers to....
I will start this off with my previous video of a single stage, 5 cfm, 30 micron pump with silicone tubing, and a mityvac pump to test the pressure....The pump is hooked up to a pyrex desiccator which is made to withstand the pressure of a full vacuum. (very thick borosilicate lab-ware!). All of my materials were sourced online except for the pump which was bought locally to save on shipping costs.
[ame="http://www.youtube.com/watch?v=dPaOrX2Zikc"]YouTube - Single Stage Vac Pump + Desiccator[/ame]
If you are going to be using an electric pump to create a high pressure vacuum, you want to make sure that your chamber is able to withstand the pressure. I have seen some people use a mason jar or a foodsaver container, and it has worked for them without breaking. All I can say is that mason jars, food saver's, or most other ordinary objects that you might use which is not meant to be used as a high pressure vacuum chamber is NOT SAFE. I would just like to stress this point because it seems that many people see this as the part of the setup where they can cut costs. High pressure vacuum chambers have a decent price tag attached to them for a reason....
I have used the electric pump as well as the pump-n-seal and mityvac. So far, the best results have come from the electric vac. I realize that the single stage will lose power eventually, and am looking into a 2-stage for the future, but this pump will have to suffice for now. Don't get me wrong, the pump n seal or mityvac will produce a much better product than without the use of a vac, but both the easiest process and the best product come from the electric pump with a safe vacuum environment.
I am investigating getting a 2-stage, 6cfm pump with any micron rating of 25 or under. I am not to sure as to the specific company's reputations as of yet for the 2-stage pumps, but if you look on ebay, you can see a general price range for each manufacturer, and more or less match the quality of the maker to where they fall in the price range for that category of pump....
edit: I forgot to add that I believe the main benefit to the 2-stage pump would be a 2nd motor that kicks in to help the pump consistently pull the deep vacuum that we are looking for. With a second motor, it reduces the stress on the first motor and your pump should last longer when used repeatedly. That being said, as you see in the video, a single stage pump can pull to the desired Hg, imo the only question would be for how long?
Would love to see some video footage/pics of some of the other setup's out there.... I know people here are using the lexan sheets over steel pots, or clear polycarbonate vac chambers... lets see em!
I'm sure that many people here have great ideas for the improvement of this setup/technique.... Ways to construct a similar setup at a lower cost or a better setup at a similar cost, or whatever it may be..... so lets talk vac!
Remember: keep it on topic, constructive, and progressive!
edit: here is a short video on Proper/Safe Vaccum Chamber Procedures for a glass desiccator (supplied by FEAR420). Thought this deserved to be in the OP.
[ame="http://www.youtube.com/watch?v=Y57KvfGsB6w"]Using a Desiccator - YouTube[/ame]
edit 2: Another video posted in the thread by Detective Dank that should be included in the OP. Explaining how vacuum pressure works in a very simple way.
[ame="http://www.youtube.com/watch?v=BMil2smliVs"]Let's Play Bill Nye: Stop the Rock! 02 Under Pressure - YouTube[/ame]