Re: Drilling for conduit

["Bill Stock" <me7@xxxxxxxxxxx>]

"Lewis Gardner" <lgardner@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:46076b83$1_3@xxxxxxxxxxxxxxxxx

> For rough in work I prefer Milwaukee Selfeed bits like these:
>
> www.mytoolstore.com/milwauke/accself.html
>
> 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:
>
> www.mytoolstore.com/milwauke/3002-1.html
> www.mytoolstore.com/milwauke/1670-1.html

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
hole.

> My suggestion would be to use a bi-metal hole saw. Starrett makes the best
> I have ever used:
>
> www.mytoolstore.com/starrett/hole001.html
>
> I also like the A2 arbor:
>
> www.mytoolstore.com/starrett/arbors.html#A2

I've got a few Starretts, but none the right size I don't think.

> 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
> be used.
>
> 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:

It's not 12 solid inches, just 12" total length required. I like the 1/4"
rod idea too.


> www.mytoolstore.com/ideal/ide14-02.html
>
> 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 that task.
>
>
> Good luck!

Thanks for the advice.