Best method to determine fall with trenched pipe

[arcticfox83]

What is the best method to determine correct fall with 50 feet of trenched lateral sewer pipe? 4 foot level? Laser level? String? The old pipe I pulled out had a few bellies.

 

[NHmaster3015]

A quality laser level works very well = most expensive option

A transit or builders level works just about as well = still pretty expensive

A length of string, some stakes and a tape measure works well = a lot more work but pretty accurate

A 4' level sort of works = not much expense but a whole lot more time.

 

[Sponsor]

 

[arcticfox83]

I'm thinking about picking up a Bosch self leveling two axis line level at the end of the month. At least in this lateral sewer application it will give me accurate fall and prove that I laid straight. Are these (the two axis / dual plane) the most versatile for other applications? I might have fence post holes coming up after the sewer is fixed. Anyone have one?

Bosch GLL 3-50

Using the above laser level, since it emits from the bottom of the unit, can it get away with literally setting it on top of the high side of the pipe in the trench?

I've seen people talk about a "water level" consisting of 100 ft of 1/2 in clear tubing filled with water and window cleaner. How does that work? Are these actually used?

 

[hj]

Define what you mean by "laser level". When I hear the term, I usually thing of a laser on a tripod along with a target on a stadia rod that emits a tone when the laser contacts it. If you mean a two foot level with a laser beam that is a bit more work but still accurate. If I want to be "accurate" I use my transit and set the scope to the exact angle I want then check the lengths of pipe as I install them, but it is a two man process.

 

[Leejosepho]

For around $20.00 or so ...

 

[Reach4]

I have a Johnson 40-0921. www.johnsonlevel.com/levelPedia.asp?article=40-0921+Self-Leveling+Cross-Line+Laser+Level It is not bright enough for outdoors at a distance, but it is good for 50 feet at night if there are not bright street lights. It comes with red glasses to make the red beam more visible, but that is not enough during the day.

It is definitely DIY and not professional grade. It draws a vertical and horizontal line with a special prism on a pendulum. There are professional units. Some spin a laser beam. Some use a prism, but have more power.

The tubing works unless you get bubbles. My well water has bubbles coming out of solution after an interval, so I would need to let those settle out.