# Finally got a vacuum pump



## mikeinkaty (Mar 21, 2013)

Man, does that speed up filtering! Shoulda got one at the git-go.

I don't have a Buchner flask. I'm using a 1/2 gallon Ball-Bro. canning jar. I cut a circle out of unused copper-clad circuit board the same size as the sealing lid for the fruit jar. In that I cut a smooth hole 7/8" diameter to receive the tip of the Buchner funnel. Then drilled a 1/4" hole for a 1/4" (od) copper tube. I soldered the copper tube into the circuit board. I use a stand to support the funnel - not the jar. It doesn't make a perfect seal but just enough that the pump will pull about 10" vacuum. That's enough to cut the filtering time down by 50+ %. I may install a small bleed valve on the line to help regulate vacuum if necessary.

I also don't have a catch jar for the pump yet but that's next. That will be using a 1 qt fruit jar.

I was wondering - Since there might be fumes going into the pump, what if I put about 2" of salt water in the catch Jar and extended the intake tube down to the bottom of the jar??? Then put a little stone filter on the tube (like used in a fish tank) to make smaller bubbles. Would that help protect the pump from the fumes?

Mike


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## mikeinkaty (Mar 22, 2013)

I used the vacuum on 3 batches of cement today. Man did it go fast! Plus it extracts most of the water from the cement making the time shorter to dry the cement. It also seem to wash the cement better. After 4 washes it was passing the ammonia test for copper. It was 5 or 6 washes when gravity was doing the job.

I got the catch jar made and working tonight. I do need to get a stone to break up the large bubbles.

I don't have a perfect seal where the funnel goes through the jar lid. For a test I put a small O-ring on the funnel tip on top of the lid. Soon as I turned on the vacuum the o-ring popped down and made a perfect seal. But the vacuum guage went real high and I was afraid it might pop a hole in the filter paper so I took it off. Wrapping a piece of Saran Wrap around the tip at that spot does the same thing.
Mike


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## etack (Mar 22, 2013)

Hey mike for less than $75.00 you can have an *OK* filtering setup that I wouldn't fear to implode on me and that seals great.

http://www.lmine.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LMS&Product_Code=175193&Category_Code=filtering_flasks

http://www.lmine.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LMS&Product_Code=18276&Category_Code=buchner_plastic

http://www.lmine.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LMS&Product_Code=18272&Category_Code=buchner_plastic

This stuff isn't for the fanatical but when dealing with acids under pressure try to use the minimum. one nice thing is if you only use it for silver just wash it with nitric and it cleans right up. I use this cause I have a habit of breaking lab glass. I also have found that the filters don't fit perfectly so I use several large coffee filter and it works great. It allo gets top heavy when full of silver. 8) 

Also if your pumps is Al (sparkless) then don't use salt water it will corrode it. if you have alkaline water it might be enough to neutralize the acid fumes not that NOX bothers Al but if you filter something else.

Eric


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