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Wonder How This Would Work ?
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Author:  WudWerkr [ Fri Jan 21, 2011 9:31 am ]
Post subject:  Wonder How This Would Work ?

Ive read about the Vacumme clamping , An I see the "space bags " on tv that use a house vac to suck out the air . Has anyone ever tried this concept on glueing and vac clamping ? idunno idunno

Author:  Corky Long [ Fri Jan 21, 2011 10:09 am ]
Post subject:  Re: Wonder How This Would Work ?

Interesting thought - my guess is the clamping force exerted by this kind of setup and a household vacuum would a) provide insufficient clamping, and b) create bad domestic karma by frying your vacuum motor. :oops:

Author:  WudWerkr [ Fri Jan 21, 2011 10:45 am ]
Post subject:  Re: Wonder How This Would Work ?

Corky Long wrote:
Interesting thought - my guess is the clamping force exerted by this kind of setup and a household vacuum would a) provide insufficient clamping, and b) create bad domestic karma by frying your vacuum motor. :oops:



Shop vac would have ability i would think . If not I do have a 2 HP dust system that I KNOW would work laughing6-hehe laughing6-hehe

Author:  Barry Daniels [ Fri Jan 21, 2011 11:18 am ]
Post subject:  Re: Wonder How This Would Work ?

No dust collection system or shop vac will pull the necessary vacuum pressure of somewhere around 20 inches of mercury. For this you need a "real" vacuum pump.

Author:  WudWerkr [ Fri Jan 21, 2011 12:18 pm ]
Post subject:  Re: Wonder How This Would Work ?

You may well be correct Barry , However I see a Experiment in my near future . I will post on how it turns out with Pics , Positive or negative ! [:Y:]

Author:  muthrs [ Fri Jan 21, 2011 12:59 pm ]
Post subject:  Re: Wonder How This Would Work ?

Remember, there is a difference between high volume (air flow) and high vacuum (suction). Household vacuum cleaners and shopvacs have high volume but not high vacuum. Dust collectors have huge volume but even lower vacuum.

Author:  John Killin [ Fri Jan 21, 2011 5:29 pm ]
Post subject:  Re: Wonder How This Would Work ?

We have tired space bags used for their intended purpose and well.... they are not that reliable.

I would think they need to bee beefed up at the seams. And they tend to puncture easy. You pull the vacuum, the seal the bag with the plug. Any sharp edge causes a puncture.

Author:  cphanna [ Fri Jan 21, 2011 6:42 pm ]
Post subject:  Re: Wonder How This Would Work ?

I need to ask a question here, and I'll be the first to admit that I am ignorant about vacuum bag clamping. I understand the concept very well, but not the actual practice of the technique. Let's assume we use a household vacuum cleaner or a shop vacuum to suck air out of the bag--okay? Now, once we have the air out of the bag, we have atmospheric pressure clamping everything inside the bag together. Would it not be possible at that point to tie off or tape off the vacuum bag very tightly and remove the pumping device? Is it REALLY necessary to run the pump for the full duration of the clamping time? Frankly, it seems to me that once we have the air out of the bag, if we do a reasonably good job of preventing air from re-entering, then atmospheric pressure will do the rest. But, as I confessed, it's a question based on ignorance. I might be overlooking something here. Please tell me if there is a flaw in my thinking here. I appreciate it.
Patrick

Author:  klooker [ Fri Jan 21, 2011 8:48 pm ]
Post subject:  Re: Wonder How This Would Work ?

A good industrial shop vac will pull 92" of water which only equates to 6.8" of mercury.

My vacuum pump pulls well over 20" of mercury. You usually don't even see the wrinkles come out of the bag until you get over about 14" of Hg.

Kevin Looker

Author:  TonyKarol [ Sat Jan 22, 2011 7:45 am ]
Post subject:  Re: Wonder How This Would Work ?

Yes there is a flaw in your thinking .... any small puncture or imperfection in the seal will let air in - so sealing it reasonably well wont do (think air in a balloon - it eventually goes thru and deflates because its not perfect). The vacuum in the bag is trying to draw air in, and the outside air pressure is pushing it

Author:  woody b [ Sat Jan 22, 2011 7:58 am ]
Post subject:  Re: Wonder How This Would Work ?

Like everyone else has said, the bag isn't strong enough, and a shop vac, or even dust collector doesn't pull enough vacume. You need a real bag, and a real pump for vacume clamping. FWIW, I use the "space bags" to store bulk strings in.

Author:  WudWerkr [ Sat Jan 22, 2011 10:17 am ]
Post subject:  Re: Wonder How This Would Work ?

Thanks for all the replys on this , I halfway expected to have people ignore this one. I guess its a idea that probably wont work , based on the comments ive seen and tend to think are probably correct . duh

Well , its like dad always said " boy ive warned you about thinking " laughing6-hehe laughing6-hehe

Seriously thanks for the input everyone ! [:Y:]

Author:  Randolph [ Sat Jan 22, 2011 11:49 am ]
Post subject:  Re: Wonder How This Would Work ?

You could, perhaps, wrap your lips around the end of the hose and have a friend punch you in the stomach. The resulting impact would most certainly cause enough suction to properly seal the bag. Now, vacuum setups have a built in pressure sensor that accounts for inevitable escaping air (small leaks). This sensor then turns the system on, again ..... and again. You would, therefore, have to find a friend that is willing to hang in there, over time, and deliver multiple punches over a 4 - 6 hour period. We would be very interested in the outcome. ;)

Author:  WudWerkr [ Sat Jan 22, 2011 1:08 pm ]
Post subject:  Re: Wonder How This Would Work ?

Randolph wrote:
You could, perhaps, wrap your lips around the end of the hose and have a friend punch you in the stomach. The resulting impact would most certainly cause enough suction to properly seal the bag. Now, vacuum setups have a built in pressure sensor that accounts for inevitable escaping air (small leaks). This sensor then turns the system on, again ..... and again. You would, therefore, have to find a friend that is willing to hang in there, over time, and deliver multiple punches over a 4 - 6 hour period. We would be very interested in the outcome. ;)



:shock: idunno [uncle]

Author:  cphanna [ Sat Jan 22, 2011 2:00 pm ]
Post subject:  Re: Wonder How This Would Work ?

Yep, I see your point, Tony. Thanks.

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