Bubbles in manometer

[buddhasummer]

I made a manometer but have discovered when I try to fill the tube with water lots of bubbles appear throughout the tube rendering it useless. I suspect the tubing is too narrow, I'm using tubing of about 4mm, but am not sure. If anyone can advise I'd be most grateful. TIA.

 

[Zung]

In the beginning, there's some sort of skin effect that traps air; shake well, lightly suck/blow in it, and they'll go away, eventually. Replenish as required.
I use 6mm tubing, but DA Aquamaster once said the smaller tubing is better.
In my area, tap water leaves a white deposit, so I use demineralized water.

 

[buddhasummer]

In the beginning, there's some sort of skin effect that traps air; shake well, lightly suck/blow in it, and they'll go away, eventually. Replenish as required.
I use 6mm tubing, but DA Aquamaster once said the smaller tubing is better.
In my area, tap water leaves a white deposit, so I use demineralized water.

great, thanks for the reply ill give that a go.

 

[herman]

Shaking and tapping should get them to go. "Rocking" the fluid back and forth by gently blowing and sucking the tube helps as well. Try to fill the tube in a manner that introduces as few bubbles as possible. If you have access to a syringe, use that to fill it, placing the tip of the syringe against the tubing and allowing the water to flow down the wall of the tube using that same skin effect instead of straight down the tube which tends to trap bubbles. You might also want to wash the insides of the tube with hot soapy water to remove any waxy/oily residue that might be on the tube.

The bubbles will eventually work their way out. Adding food coloring to the water makes the water easier to see.

 

[buddhasummer]

Shaking and tapping should get them to go. "Rocking" the fluid back and forth by gently blowing and sucking the tube helps as well. Try to fill the tube in a manner that introduces as few bubbles as possible. If you have access to a syringe, use that to fill it, placing the tip of the syringe against the tubing and allowing the water to flow down the wall of the tube using that same skin effect instead of straight down the tube which tends to trap bubbles. You might also want to wash the insides of the tube with hot soapy water to remove any waxy/oily residue that might be on the tube.

The bubbles will eventually work their way out. Adding food coloring to the water makes the water easier to see.

Cheers, not having much joy, will try some hot water and soap. Thanks again.

---------- Post added April 21st, 2013 at 07:31 AM ----------

Running some hot soapy water through the hose fixed the issue. Thanks again.