"blueman" wrote in message
...
blueman writes:
I need to run a wire from a switch on the wall up the wall and across
the ceiling to a new overhead light. (Note that unfortunately, the
joists run perpendicular to the direction that I need to traverse the
ceiling)

Doing so presents the following two problems for me:
1. How do I make the right angle turn through the top plate and into
the ceiling joist bay?

2. How do I go through the joists as I traverse the ceiling from the
wall edge to the center light location?

Note I don't have the option of using an unfinished attic or basement
to help me. I am trying to avoid ripping up more plaster than I need to.

I plan on buying a long flexible 1/2" bit which I believe should at
least help me with #2, though I'm a bit short on the details of where
I drill the entry and exit holes and how I achieve the right bend and
angle to go through the middle of the joist.

However, I am a lot more stumped about how I make the right angle
transition from the wall bay into the ceiling joist bay.

Could anybody give me some detailed pointers and/or point me to any
online videos? (I tried googling but found only general suggestions
such as using a flex bit)

Thanks.

Here is my report back on what I did and how I did it.

I ended up going the direct route of snaking across the ceiling and
down the wall. Again, my primary priority was doing this in a lasting
and professional way since I feel an obligation to the generations of
previous owners of our historic house (main part is Italianate built
in the 1860's and the garage is part of a wing that reportedly dates
back to the late 1700's!!!).

First, cutting through the ceiling was even harder than anticipated --
even to just cut out the hole for the ceiling box and the intermediate
holes for snaking the wires. There were multiple layers. Starting from
the exterior:

1. Rough 1/2" layer of hard plaster/stucco
2. Tough metal lathe. Actually the lathe on the ceiling was mostly solid
metal with some grooves. The lathe on the sides was thick fine
mesh.
3. Another 1/2 layer of plaster keyed into wooden lathe
4. 1/2" wooden lathe
5. Loose fill insulation (not sure what it is but it was very light,
gray in color and almost like very light sawdust or cotton whisps)

I needed to use a diamond cutter in my rotary zip saw to cut through
the stuff and it made a real mess -- unfortunately, I didn't have a
helper to hold a shop vac...

fyi: diamond tools don't last long cutting metals. you want to try an
abrasive type of cutting tool instead.