Calibrate a level?

[PoorOwner]

Is it possible to calibrate the bubble of a 4' level against a known good one..

my new stanley fatmax which I DID NOT drop yet can be a good reference.

I also dropped a small topedo level yesterday :(

I know, stop dropping them but sometimes I tackle 2 person job on my own.

[boiler7904]

You don't even need a second level.

Put the level on a surface that is relatively level and see where the bubble is. Turn the level 180 degrees end for end in the same location and see where the bubble is. It should be in the same spot if the level is correctly calibrated. Do the same test on a vertical surface to check for plumb.

[PoorOwner]

so do you try to loosen the screws or whatever holding it and adjust if necessary?

[boiler7904]

You've got it

[Abodyracer]

what brand is it? If C-man its warrantied, take it back and exchange it.