Vacuum generator venturi - any made one?

I want to try putting together a quick vacuum generator that runs off compressed air (run of an 8 gallon tank up to 130 PSI.

I'll be using it for desoldering so I think I want a reasonably strong vacuum, but the volume is not all that high. It will probably be used in "burst mode" - with a burst of vacuum for a few seconds being needed intermittently.

Heaps of googling and patent searching has turned up lots of commercial products and on or two water powered vacuum generators but not much in the way of pneumatic ones.

I'm hoping for a real quick & simple design - any build one or point me to some plans?

thanks D.

Reply to
Den
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I've not made one before but have used the likes of this

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, Cheap and seemed to work well for the purpose which was to draw the air from a bell jar for vacuum de-aerating some silicon moulding material. Hope that helps or do you specifically want to make one.

Reply to
David Billington

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Harbor Freight use to have one in their inventory, not sure if they still do. ...lew...

Reply to
Lew Hartswick

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I'm a cheap skate - good link but, it's available from the distributor in my part of the world too. At that price it's not worth the effort of trying to make something. Other commercial units I found were 3 or 4 times this price. Thanks - I need something else from RS, I might just expand the order...

Reply to
Den

Well, having bought a "proper" solder / desolder station several years ago, without vac pump, I sniffed around places like surplus center, goldmine etc. and ended up with a small compressor, 12 volt, that works a treat. Just get one that has a hook-uppable "suck" port. This one is about C or D size battery, including motor. Footswitch made it usable for those without 3 hands... /mark

Reply to
Mark F

Check the drop box. I think Nick Mueller posted some plans. Also, they're available from Harbor Freight for well under $20:

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?itemnumber=92475

Reply to
Don Foreman

Nick Müller has a pdf on a 2 piece pump that is VERY simple to make. It is made using one male air line connection and a piece of hex stock. If you don't find it drop me a quick note at csr684 AT yahoo DOT com and I can send it to you. It is a single page pdf.

Reply to
Steve W.

On Sat, 16 Aug 2008 20:52:12 +0800, with neither quill nor qualm, "Den" quickly quoth:

They're noisy, wasteful, and don't suck as well as they should.

But don't reinvent the wheel when models are available:

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(I'll believe 28.3" of mercury when I see it.)

Better yet, go carbon:

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or
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-- Challenges are gifts that force us to search for a new center of gravity. Don't fight them. Just find a different way to stand. -- Oprah Winfrey

Reply to
Larry Jaques

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Do a search on "vacuum bagging". Nearly all the sites selling vacuum bagging supplies sell a small air operated vacuum generators.

Or just make one. They are just a venturi in an air line tapped for a vacuum line at the smallest portion of the venturi.

Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)

Reply to
Bruce in Bangkok

Jeez - too many options! I've got a surplus little 12V compressor in my junk pile, I'll go and pull the covers off and see whats inside. Did you use a tank/reservoir or "turn on to suck"? thanks

Reply to
Den

Unfortunately I'm downunder - surplus stuff is hard to come by & we don't have a harbour freight! You guys in the states (well some of you at least) seem pretty lucky having access to surplus gear & stores like harbour freight.

Reply to
Den

Hi Steve - I've sent you a PM. thanks

Reply to
Den

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Wes

Reply to
Wes

On Sun, 17 Aug 2008 19:29:21 +0800, with neither quill nor qualm, "Den" quickly quoth:

Ouch! Shipping to/from AU really sucks since everyone doing it adds a quintuple charge to do so. I thought you had a store like HFT down there, though. From what I've gleaned here and on the Wreck a few years ago, much of our HFT/Northern stuff is available in Canada at Crappy Tire or Princess Auto. I could have sworn that you had a similar outlet there. How about eBay.au?

Amen to that. We're triply blessed with Surplus Center, Northern, and HFT.

Speakni of surplus, I just saw today's

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offering: A recertified 750GB SATA/300 hard drive for $77.77 + $5 s/h. 750GB on a

3.5" form factor drive. UFR!

I paid $300 for my first hard drive, a 20MB Seagate.

-- Challenges are gifts that force us to search for a new center of gravity. Don't fight them. Just find a different way to stand. -- Oprah Winfrey

Reply to
Larry Jaques

I use vacuum clamping for CNC routing - and my vacuum pump is an old (~25 yo) refrigerator compressor. It's low CFM, but pulls 24+" of vacuum and is nearly silent.

It'd be fairly easy to expand the capacity by using a small air tank, and a sensor/switch of some sort to control the compressor would be a real convenience.

Reply to
Morris Dovey

A commercial unit is the "Ped-a-Vac", I think it has a 2-stage venturi system, and gets a strong vacuum even with some leakage at the tip. You might look on eBay for one.

Jon

Reply to
Jon Elson

I just use the venturi effect on an air brush, connect a small hose to the spiggot that usually sits in the little glass jar. I just let the compressor cycle on and off when it drops pressure.

For bagging I use ziplock, with some Blutack to seal the hose and bag properly. Recently I lashed out on a pair of automotive brake hose clamps to close off the vacuum hose.

Reply to
noonehome

Hell...check the second hand stores for a breast milk pump.

I picked up a really neat looking pump for desoldering..all chrome and nicely made...and when I got it home..the ex asked what I was doing with a breast milk pumping unit....blink blink....is that what it is??????

Gunner, who keeps a speculum on the coffee table to embaress guys and make their wives laugh their asses off at them.

The hottest places in hell are reserved for those who in times of great moral crisis maintain their neutrality", John F. Kennedy.

Reply to
Gunner Asch

Some shiny clear acrylic speculums appeared as "ice tongs" at a birthday party many years ago. Pretty much all of the guys were oblivious to what they were and they had a hard time loading ice into their drinks.

PS - they were new & unused.

Reply to
Den

"Den" wrote in news:48a6cd7f$0$8684$ snipped-for-privacy@per-qv1-newsreader-01.iinet.net.au:

All you need is a quick coupling for your air hose, a 4" piece of 1/4" copper tube, 1/4" fitting to go from the coupling to the copper tube, 1- Tee, (a Y would be better, but hard to find) a check valve and a vacuum storage vessel.

Cut 1" off of the copper tube, sweat it to the stick leg of the T. Cut the rest of the tube in half, insert T and sweat together. Sweat on fitting and attach coupling. Check valve goes on the stick leg of the T. Connect check valve to vessel, connect air hose. vacuum being generated for cheap parts cost.

I made and used one in another life to suck the air out of dump truck tire inner tubes. It'll suck a complete vacuum in one of these huge inner tubes in about a minute or less.

Reply to
Anthony

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