I have built a simple vacuum jar from :
- massage cup vacuum pump,
- check valve,
- hex nipple with o-ring,
- quick coupler,
- airline socket fitting
I drilled a hole on jar ( 12mm dia ) and mount hex nipple with o ring. I mount 11mm o-ring on other side of jar for sealing and it worked. 🙂 I mount airline socket fitting and quick coupler. I could able to put in mouth of the airline socket to the massage cup vacuum pump’s green gasket.
I have measured vacuum by using a syringe. I left 1ml air in atmospheric pressure in syringe and sealed the tip. Under vacuum, syringe moves till 2.5 ml. If we consider friction, we may say pressure in the jar is less then 0.4atm.
Here is the video of vacuum jar. If you want to watch construction steps, move to 3:27 , measurement with syringe 2:37