Just to make it a bit more confusing...
I have had numerous level gauges in the past. Expensive ones, cheap ones. When i had to put something against a wall wich needed to be level i tried my very best every time.
Then, one time i used a level, and the mounted object still looked "not-level". Then i figured out that when i turned the level gauge around, it would show a different measurement than the way i first started out with.
This can mean only two things. 1) I have an el-cheapo level gauge wich needs to be thrown in the garbage can, or 2) No level gauge in the world is exactly LEVEL. (wich i doubt).
The thing i learned : I'll never trust a level-gauge just like that.
Lately, for rough measurement i used a long hose filled with water, holding both ends near the measured object. That seemed to work well, but a lot of hassle.
Good luck, get level
Ed.
Not the horse, of course of course...
Building my own Scrapheap challenge CNC, or is it Junkyard wars CNC?