Venturi Vacuum Clamp

This is a vacuum clamp I designed for use with a venturi vacuum device. I use an adjustable pressure control valve to control the input pressure per the vacuum device's specified limits. With a diameter of 2.755 and thus a surface area of (3.14159 * r^2) 5.961 in^2 and a vacuuum pressure of -80 KPa (11.6 lb/in^2), I'm getting around 69 lb of force with this. Which is all to say... this thing really sucks! :-)

NOTES:
1) I had to use a clamp to press the o-ring into the groove and then glued it with a rubber cement.
2) I tried this on machined steel surfaces and BCX plywood surfaces and I only noticed about a 2 KPa drop in vacuum (0.29 lb/in^2) or less than 2 lb of force lost.


Products I Used (( NO AFFILITIONS / Use anything as good as or better than the ones I listed ))
Buna N O-Ring Cord: https://smile.amazon.com/dp/B00QVB4UTO?psc=1&ref=ppx_yo2ov_dt_b_product_details
1/4" OD Check Valve: https://www.amazon.com/DGZZI-Straight-Connect-Reverse-Osmosis/dp/B0855KMH6X
Ven