I'd like to run some 2" flexible conduit from the basement to the second
floor (possibly attic). I've already got several smaller holes drilled
through the first and second floors in this wall. I've also got two access
panels on the 'inside' of this center wall. But a recent wiring experience
convinced me that I need a better solution.
I've read that a forstener bit with a right angle adapter is the best tool
for the job. But considering I need to drill about 12", I'm wondering how
difficult it is to control this beast and keep the hole close to straight. I
know from my previous adventures that the three stud walls don't line up too
well. I was hoping that there is some sort of guide that I could mount
between the studs to keep the hole straight.
Any insights appreciated.
Milwaukee makes some drills specifically for this purpose. They are similar
to forstner bits except that the outer ring has many teeth along it (but not
as many as a hole saw) and there is a screw center to help pull the bit into
I like the idea of using a right angle adapter. I have been wondering how I
am going to get the bit and drill close enough to straight without making a
massive hole in the wall.
I would think that once you get the hole started in line with your hole in
the wall, that it would be easy to see when a right angle adapter was square
to the wall.
to forstner bits except that the outer ring has many
help pull the bit into the wood.
When we bought an older home some years ago I needed to do the same thing. The
walls were plaster over wood lath and nothing lined
up. I found it much easier to locate a closet on the second floor that was
partially over another closet on the first floor. I
used a Milwaukee hole saw to cut two large diameter holes in the floor of the
2nd story closet and through the ceiling of the 1st.
I did the same thing in the first level going down to the basement. I punched
through to the attic and installed two wiring
cabinets there and two more in the basement. A few offset fittings eliminated
the need to bend 2" EMT (I've never been good at
conduit bending) to fit snugly onto the corners.
"Bill Stock" wrote in message
I've found the secret is to drill inspection holes and have a helper report
the bit position as you drill down.
I've used a microcam and white LED taped together to look into holes where
I've encountered unexpected obstructions (a broken off hammer head!), but a
helper, a teeny flashlight (I use a $12 fiber optic attachment that MagLite
sells for its AA flashlight) and some inspection holes along the *intended*
path of the bit works well.
You might be able to detect the drill shaft with a studfinder as well, but
I've never tried it because I never had a studfinder that would be as good
as a small viewing hole. If you're drilling big holes, you're going to do
patching work on the walls anyway . . . At least that was my opinion. I was
drilling 2 3/8" holes in oak flooring for central vacuuming outlets.
What I would really like is one of the X-ray rigs they use to scan trucks at
border for illegal immigrants. No doubt about where the drill's going if
you can see it through the wall.
I like the inspection cam idea, where did you buy and what model? I put a
day/night cam on a model car once to inspect the larger hot air ducts. :-)
Yeah, I'm sure there is something else in the way between the top plate and
the sole plate, based on my previous drilling adventures.
After taking the wall apart for the third time, I built a permant hatch with
J Channel and drywall. It doesn't look TOO bad all painted up. So access is
not an issue. There's a similar hatch inside the kitchen cupboards on the
There's *always* something funky in between the studs. At least there has
been in my experience when drilling more than one hole. After angsting
about drilling through the overstressed joists in my basement for weeks, I
finally decided to strap the vacuum cleaner pipes to the joist bottoms. Not
as clean, and it will cost me a few inches come finishing time, but no
amount of engineering assurances made me feel comfortable enough to bore
2.5" holes in support lumber in this old house!
The first camera I bought was a small head with the electronics further down
the cable. PC233XP Color Microvideocam at Supercircuits.com. It cost $134
but I had other uses for it, so it wasn't just a "search cam."
Sadly, it's not listed anymore. Only much more expensive cameras, but
that's not a problem. As these things often go, I ended up using the
microhead camera elsewhere because the smaller cam's "electronics bulge" got
caught on a nail point sticking out of a stud. I thought I was going to
lose the whole freaking thing inside the wall but a few minutes of nervous
fishing freed it.
It turned out that I had an ExView color bullet cam that lost its water seal
and had to be retired from outdoor service but was still quite useful once
it had dried out. I realized then that the smooth, streamlined design of
the bulletcam was useful to avoid nailpoint and splinter snags. Since I had
it opened up to try to restore the seals, I was able to adjust the focus to
much closer than its stock setting. Whatever camera you get, close focus
ability is an absolute must.
I had a tiny USB Targus LED for lighting laptop screens that I wasn't happy
with so I cannibalized it and taped it to the side of the bullet cam. It
has a nice, diffuse light perfect for hole scanning! Since the cable comes
out the back, bullet cams turn out to be pretty useful for "diving." I've
got a little 13" color TV with AV inputs that makes a good viewscreen for
searching. I tried using a small LCD handheld, but the resolution's not
good enough to make sense of the jumble of junk that's often sitting on the
It's easy to see why plumbers have been using access panels for a long, long
I'll be there's some hi-tech gyroscopic GPS laser control system for
professionals who install a dozen central vacuums a week.
For rough in work I prefer Milwaukee Selfeed bits like these:
However for what you are trying to do they might not be the best choice.
First problem is cost. You only need to drill a couple of holes and $35
is fairly expensive. Second you are likely to hit some nails. In rough
in work you can see the likely nail locations and avoid them. A selfeed
will mangle it's way past a nail but you will need a stout drill motor
to do that. Third is the stout drill requirement, you will not be able
to drive a 2 9/16" selfeed with a homeowner type drill and right angle
adapter. You will need something like either of these:
My suggestion would be to use a bi-metal hole saw. Starrett makes the
best I have ever used:
I also like the A2 arbor:
The advantages for your application are:
1. You can dill a pilot hole first with a 1/4" bit and see where it goes
then follow that hole with the hole saw. If you really want to be sure
you don't wander replace the arbor's pilot bit with a piece of 1/4" rod.
2. A bi-metal blade will cut through nails, gently.
3. Since you are not removing as much material a smaller drill motor can
It will be a slower process with the hole saw than with a selfeed but
you don't have that many holes...
If you are drilling through 12" of wood you will need some extensions
either way you go. Hopefully you have a 1/2" drill so you can use 7/16"
standard extensions. Here is a 12" but they come in various lengths:
With a hole saw you will have to stop every inch or so and remove the
plug of wood from the hole (or saw). A stout screwdriver is good for
I have no connection to mytoolstore.com and I have never used them.
Their site came up quick on Google and their URLs were short...
On Mon, 26 Mar 2007 02:43:16 -0500, Lewis Gardner
wrote in message
Folks that 'graduate' to a powerful hand drill might not realize that their
high torque can make them dangerous if not used with caution and skill. If
the bit bind, they don't necessarily stop, rather, they can smash your hands
or face or whatever else is in the way.
Years ago, a friend of mine who also something of a tool and safety freak
lost a substantial part of his long beard in a split second. Ouch!
Great tip! My knuckles would have appreciated it ;-)
If the baseboards are tall then sometimes you can get away with pulling a
section of one and cutting the hole behind it. But then there's usually not
enough vertical room to get the drill and bit in there together. So then
you've got to cut an opening for an inspection hole and get a cover. Then
use extensions are Lewis suggested. There's really no good way to avoid it
if you want to drill anything larger that what the usual flexible auger bit
can make. You can usually paint the covers if you don't want to repaint the
I purchased a dewalt cordless right-angle drill a while back (for running
some wiring in a boat) and it's been tremendously useful for other stuff
too. I've tried the various right-angle adapters over the years and most
really aren't worth the hassle. They're generally no good for anything
light duty work. But the dewalt has been great for the various holes I've
needed to wire up our Russound stuff.
Depending on how much wiring you're doing it's sometimes better to find a
good alternative location to run "everything" and cut the wall open. Or
even create a box or false panel inside a closet to contain it all.
Sometimes you have to factor the costs and hassles of running it where you
want, versus running it where it's easier. The added tool and repair work
costs sometimes overwhelm what it'd cost in re-routed wiring and replacing a
whole section of drywall in that out of the way location.
Just remember if you're using conduit that it's not a good idea to assume
you can pull more wire later if the conduit is more than half-full. You end
up gouging or otherwise damaging the existing wires if you try to pull more
stuff later. And bends in the conduit make that an even bigger hassle.
Then make sure you follow the electrical/local codes on dealing with the
ends of the conduits.
I've got a Makita 1/2" Hammer drill. Not as nice as these, but it should do.
As Marc indicated I nearly broke my thumb with it once drilling a large
I've got a few Starretts, but none the right size I don't think.
It's not 12 solid inches, just 12" total length required. I like the 1/4"
rod idea too.
Thanks for the advice.