Having trouble with getting straight pipe runs using a david white line instrument been coming up a foot off the manhole.what am I doing wrong?
What procedure are you using to line it up ? Photo of setup would help
We set a tripod over a manhole and plum down to the center of the pipe laser sometime there's not enough room in a small structure to set the laser in the manhole were starting at so we put the laser inside the first joint lining the david white to a probe rod. Then matching the laser to the probe rod
Welcome to the Forums Buddy Rowe! That's the way we do it with a David White line transfer unit. Has the LTU been dropped or damaged? When was the last time your laser was callibrated?
Not sure its been with the old foreman for a while now.
I think I would have the laser calibrated.
Okay thanks I'll get it sent off
Can't you check it by shooting a run one way, then moving and shooting back the same run? how much you're off show how accurate you are, and if that's close enough for the work you're doing. Figuring out exactly where that error comes from is a little tougher, but that at least gets you and idea of what's going on.