Posted by Me on November 6, 2005, 6:51 pm
Aanyone with any brains would take pictures of the PEX installation
with their digital camera and keep them around for later use.
Posted by Solar Flare on November 6, 2005, 6:58 pm
Maybe "anybody with any brains" didn't have a digital camera before they were on
Posted by Iain McClatchie on November 6, 2005, 10:58 pm
SF> Maybe "anybody with any brains" didn't have a digital camera before
SF> they were on the market.
Even if you did, I doubt you could use a set of pictures to determine
where the PEX lines were, to enough accuracy to avoid them. Just try
to imagine what your procedure would be:
1) For each straight run of PEX, draw a line to a wall, find the
2) Find that same point on the real wall. Note: you must be accurate
few inches, for every single point.
3) Snap chalk lines between the points marked on the walls.
I've got a decent digital camera, and have shot a ton of pictures of
our lot, on which I've tried to superimpose scaled shots of our house
model. There are tons of trees and survey stakes to act as benchmarks.
-- It's really tough to get close. I wouldn't want to bet I've got
every wall within four feet of where it's supposed to be.
Posted by Anthony Matonak on November 6, 2005, 11:26 pm
Iain McClatchie wrote:
Let's try to imagine what the procedure could be...
If this is the days before digital cameras (or you are cheap) then
you use a film camera. Let's say one of those $ 35MM cameras you
can find in almost any department or toy store.
When snapping photos care is taken to mark on a floorplan (or survey)
where exactly the photos are being taken from, with permanent landmarks
included in the shots. Several shots of the same location, from the
same perspective, should be shot to give before, during and after.
This should be enough, if care is taken to make the appropriate shots,
for someone to map out the pex, studs, wiring and everything else to
within sub-inch accuracy after the fact.
If someone wants to do a quick and dirty "where are my pipes" thing
then all they need is a projector (slide project if you have slides
or opaque projector for prints). Project the image showing the pex
on the real floor so that it lines up with the landmarks (walls,
corners, outlets, etc). If the projected image lines up exactly
with visible features then it will line up exactly with invisible
ones like the pex buried in the floor.
I have heard people have been working on GPS equipped cameras and
head mounted displays to give a kind of building 'x-ray vision'
using this technique but I don't know how far along they are.
Posted by Solar Flare on November 7, 2005, 3:02 am
I doubt the lens used and the projector lens would be within 12 inches of
distortion from each other.
Nice idea but with a grid that fine not likely.
PEX with a metal tracer could be found with a metal locator or a signal locator.
Fill your pipes with mercury for locating.