Is an electronic vacuum necessary for creating a vacuum in a vacuum container?

[paradisePhysicist]

Hi I purchased a vacuum container on amazon, the type with the glass and rubber lid. I didn't want to spend a bunch of money to buy an electronic air vacuum so I just bought a hand pump instead. Only problem is the hand pump doesn't seem to create a vacuum, even though I verified the hand pump does create a vacuum in the tube itself.

The manufacture told me that the vacuum container is not defective, and that I just must buy an electronic vacuum instead of a hand pump or else it will not create a vacuum. I am wondering is this a common occurrence, and if so, which electronic vacuum should I buy? Ideally it should be cheap and also able to do other things, such as blowing air for cleaning dust from computers.

Another thing I thought of is to somehow put tinted air into the vacuum container, the tinted air would look different from the regular air in order to see what exactly is going on. I just thought of this though and not sure what is the cheapest way to tint air. I thought about boiling water but I don't want to risk damaging the device.

 

[Baluncore]

Only problem is the hand pump doesn't seem to create a vacuum, even though I verified the hand pump does create a vacuum in the tube itself.

Can you provide links to the vacuum container and to the hand pump.
It may be as simple as the position of a non-return valve.

 

[paradisePhysicist]

Can you provide links to the vacuum container and to the hand pump.
It may be as simple as the position of a non-return valve.

Alright, the hand pump is here:
https://www.amazon.com/gp/product/B08TBBD7DK/?tag=pfamazon01-20

vacuum is here:
www.amazon.com/gp/product/B01A359IU4

 

[berkeman]

I just bought a hand pump instead.

What level of vacuum do you want to pull? What is the application?

I had one of those type of hand pumps and used it for many years to bleed the brakes on my motorcycles. They are not made to pump down a large volume like the vacuum jar you have.

 

[paradisePhysicist]

What level of vacuum do you want to pull? What is the applications?

I had one of those type of hand pumps and used it for many years to bleed the brakes on my motorcycles. They are not made to pump down a large volume like the vacuum jar you have.

Ideally close to 99% vacuum but it doesn't even seem to do anything, after dozens of pumps there is no pressure change. If the hand pump is not strong enough to initiate a vacuum seal, maybe there is some kind of liquid or something I can put on the rubber to create more of an air tight seal? The application is I want to test the effect on sound and also foods.

 

[Baluncore]

Pull a vacuum with the hand pump connected to the chamber, while you watch the gauges.
Do the gauges agree? If they disagree, check that the valve between the vacuum pump and chamber is open and free to pass air. Check the other valve is closed.
Because the handpump is small it will take quite a bit of exercise to pump out the chamber.

 

[Lnewqban]

You have 346 cubic inches of molecules of air, increasingly hard to catch and remove from the container, by using an increasingly inefficient pump that has a displacement per stroke of a fraction of an inch.
Perhaps your most practical solution is an electric mini oil-less vacuum pump.

 

[berkeman]

Ideally close to 99% vacuum

What is the application?

 

[paradisePhysicist]

Pull a vacuum with the hand pump connected to the chamber, while you watch the gauges.
Do the gauges agree? If they disagree, check that the valve between the vacuum pump and chamber is open and free to pass air. Check the other valve is closed.
Because the handpump is small it will take quite a bit of exercise to pump out the chamber.

How do I pull a vacuum, I am not sure what you mean. I cannot get a vacuum to start in the first place. I have tested that the hand pump is working and the gauge is working, I closed the valve to the main vacuum area and the hand pump was able to create a vacuum in just the tube.

 

[paradisePhysicist]

You have 346 cubic inches of molecules of air, increasingly hard to catch and remove from the container, by using an increasingly inefficient pump that has a displacement per stroke of a fraction of an inch.
Perhaps your most practical solution is an electric mini oil-less vacuum pump.

Hmm which model do you recommend?

Also I looked on the amazon link but didn't find where it lists the displacement per stroke of the hand pump. I got into it with the mindset of "however many strokes it takes" but didn't expect nothing to happen after 50 strokes. I was expecting it to maybe take 500 strokes but notice a change after 50.

 

[paradisePhysicist]

What is the application?

To test audio and various foods to make food last longer. I am looking for an oil-less pump because I am not sure if the oil is safe for the foods.

 

[berkeman]

To test audio and various foods to make food last longer. I am looking for an oil-less pump because I am not sure if the oil is safe for the foods.

Do you mean like this?

https://spy.com/articles/hacks/kitchen/best-vacuum-seal-food-bags-256242/

 

[Lnewqban]

Hmm which model do you recommend?

Also I looked on the amazon link but didn't find where it lists the displacement per stroke of the hand pump. I got into it with the mindset of "however many strokes it takes" but didn't expect nothing to happen after 50 strokes. I was expecting it to maybe take 500 strokes but notice a change after 50.

Sorry, I have no experience with that type; only with bigger oil vane vacuum pumps.
You may need to prime the manual pump with some pre-vacuum, since the thing contains a check valve that seals better with some pressure differential.

 

[paradisePhysicist]

Do you mean like this?

View attachment 283386
https://spy.com/articles/hacks/kitchen/best-vacuum-seal-food-bags-256242/

I tried a vacuum bag for travel clothes but it didn't create a real vacuum, or at least not enough to pop a marshmallow. The goal is to dry the foods so no air is in the foods, for dried fruit.

 

[paradisePhysicist]

Sorry, I have no experience with that type; only with bigger oil vane vacuum pumps.
You may need to prime the manual pump with some pre-vacuum, since the thing contains a check valve that seals better with some pressure differential.

Hmm how would I do that, the tube thing I did earlier but then immediately open the valve?

 

[Lnewqban]

Hmm how would I do that, the tube thing I did earlier but then immediately open the valve?

If you have a bicycle air pump, you could try this:
https://www.wikihow.com/Make-a-Vacuum-Pump

 

[paradisePhysicist]

If you have a bicycle air pump, you could try this:
https://www.wikihow.com/Make-a-Vacuum-Pump

Hmm, how much vacuum would that create, could you get 99% vacuum with this?

 

[Lnewqban]

Hmm, how much vacuum would that create, could you get 99% vacuum with this?

I don't believe so.
But you could initiate the process with it and then switch to the hand pump you have.
For achieving real high vacuum level, you will need an electric pump running for some time, so all humidity is eliminated.

 

[Keith_McClary]

If you have a bicycle air pump, you could try this:
https://www.wikihow.com/Make-a-Vacuum-Pump

I've seen "Making a Fridge Compressor Into a Vacuum Pump" but not tried it myself.

 

[Tom.G]

I have one of that style pump, here are the measurements I just took:

Bore: 0.75in (estimated)
Piston area: 0.44sq.in.
Stroke: 0.95in.
Displacement: 0.42cu.in.

Vacuum pump alone:
1st stroke: -570mmHg
2nd stroke: -680mmHg
3rd stroke: -720mmHg That is maximum vacuum of bare pump.

Vacuum attached to approx. 910ml container:
100 strokes: -400mmHg
200 strokes: -640mmHg That is very close to maximum, needle barely moved.

Conclusion: That pump can not get even close to your target.

Cheers,
Tom

 

[paradisePhysicist]

I don't believe so.
But you could initiate the process with it and then switch to the hand pump you have.
For achieving real high vacuum level, you will need an electric pump running for some time, so all humidity is eliminated.

That is a clever suggestion, will try that, thanks.

I have one of that style pump, here are the measurements I just took:

Bore: 0.75in (estimated)
Piston area: 0.44sq.in.
Stroke: 0.95in.
Displacement: 0.42cu.in.

Vacuum pump alone:
1st stroke: -570mmHg
2nd stroke: -680mmHg
3rd stroke: -720mmHg That is maximum vacuum of bare pump.

Vacuum attached to approx. 910ml container:
100 strokes: -400mmHg
200 strokes: -640mmHg That is very close to maximum, needle barely moved.

Conclusion: That pump can not get even close to your target.

Cheers,
Tom

Hmm that's unfortunate, thanks for the data though. Id assume the vacuum would be even less in a larger gallon sized container.