laser levels

[hogster]

what's the general opinion of laser levels? just want something pretty basic for using when putting up shelves etc,just wondering how they fix to the wall for "easy hands free operation"....notice the B&D models have pins....doesnt that mark the walls/surface,any advice would be much appreciated.

 

[Softus]

Many cheap/simple ones just cast a single line - IMHO if it doesn't cast a line all around the room then it wouldn't be of much use.

If you're putting a shelf on a wall then you'd be better off using a traditional spirit level of good quality.

 

[cuttertree]

if you get a laser level always use a spirit level to final check the level.

 

[soaringjock]

tell me you forgot to put a smiley after your comment cutter.

 

[Softus]

If you use a spirit level then always use a water level to check the level.

 

[markie]

Then after the above, eye it in just to make sure.

 

[Softus]

...and it's worth getting a second opinion, so get a mate to check it with his laser level...

 

[breezer]

on the laser, would it need to be set somewhere between bulldozer and eyeball?

 

[noseall]

don't forget, over long distances the horizon is slightly curved.

 

[Softus]

Does that mean that it's less curved over short distances?

 

[noseall]

Does that mean that it's less curved over short distances?

relative only to differential comparison and veiwing perspectives

a builder of bridges over great distances will need to set very tall supporting columns further apart at the top than the bottom to allow for the curvature of the earth, even though they are exactly the same height (from a datum).

 

[Softus]

...need to set very tall supporting columns further apart at the top than the bottom...

Does that mean that very short columns would not need to be set further apart at the top?

 

[noseall]

Does that mean that very short columns would not need to be set further apart at the top?

yup.

 

[Softus]

So what's the smallest tower height that would require this setting-apart-at-the-top business?

 

[noseall]

your response to my tower distance statement was fairly ambiguous, so my response was ambiguous ('yup') too.

now that you have been more specific i will try to be more precise.


if i were to build a bridge over our local canal and were to use, lets say a pair of concrete columns at 6m apart, then it would be fair to assume i could build them perpendicular and still use the same measurement top and bottom.

but if i were building, lets say the Akashi-Kaikyo bridge in Japan, then i would certainly allow a greater measurement at the top of my columns than at the bottom.