One thing I used a number of years ago on laying out and framing for a concrete
foundation is a water level. It consists of a length of clear vinyl tubing.
Half inch in diameter works well but not real critical, just if too small you
tend to get some capillary action. Make sure it is long enough to come up to
where you are wanting to level off with the rest laying on the ground. Almost
fill it with water. Water seeks its own level so the two water levels seen
through the clear tube will be level with each other. by holding it near
stakes or walls you can put level marks to measure down from or to use if they
are the right height.. This probably isn't as accurate as one of those laser
level but for long lengths I think it does real well.
Ron
----- Original Message -----
From: Dan Rossi
To: Blind Handyman List
Sent: Tuesday, October 20, 2009 9:09 AM
Subject: [BlindHandyMan] Non-euclidian geometry.
I need to call in NASA to investigate my basement. Apparently, my
basement is a very special place where Euclidian geometry goes right out
the window.
I have two parallel beams that are nice and level. The level beeps
continuously as I move it along the beams. I lay a 2X4 across the two
beams and that 2X4 shows level. So, if the two beams are level, and they
are level to each other, then a 2X4 placed across them at any point will
be level.
Here is where it gets interesting. At one end, the 2X4 is level and all
is happy. At the far end, if I level the 2X4 it is well above the one
beam. And I don't mean like a quarter of an inch, I mean like an inch and
a quarter or a bit more.
This is actually impossible. But that is why my basement must be
declared a non-euclidian zone.
I think it has to do with the fact that even if the level is off a tiny
bit, like 0.1 of a degree, over 15 feet, that is actually 5/16 of an inch.
Do that three times and you get nearly an inch. Plus the middle beam that
I was trying to level wasn't fully supported yet, so is bending and
flexing, and so was the 2X4 I was using. Add all that up and you get a
lot of error creep.
I need an 8 foot level, but not sure I can get that one passed SWMBO. I
might try using my saw guide on edge which should be pretty stiff.
--
Blue skies.
Dan Rossi
Carnegie Mellon University.
E-Mail: [email protected]
Tel: (412) 268-9081
[Non-text portions of this message have been removed]
