All of our ground spirit level vials are made from glass tubing which is ground internally to form a barrel shaped radius.

The principal of operation is that the bubble will move to the highest point of the radius as gravity acts on the liquid inside the vial. This is explained in more detail on our page explaining sensitivity.

The radius is usually quite shallow which enables the vials to detect smaller angles than the plastic type vials.

We can grind radiuses from 500mm up to 100m long in order to produce vials with a range of sensitivity from 45'(arc minutes) to 4" (arc seconds). Although the sensitivity is determined entirely by the radius of curvature inside the vial, for very sensitive vials it is necessary to maintain a minimum size to ensure that the bubble can move freely without sticking inside the tube.

We can offer advice on the best size, sensitivity and liquid type for your application. We also offer Tritium illuminated levels (also known as Betalights or Trasers) which require no power supply, have a life of up to 20 years and enable the bubble position to be clearly visible in the dark. Please contact us for more details.

Ground Tube Glass Level Vials

Circular Glass Level Vials