How to drill a cenetered hole in end of solid rod

I need to make a specialized tool and am looking for a way to drill a
1/16" hole EXACTLY in the center of the end of a piece of say 1/2" of
3/4" solid aluminum rod. In other words, I am trying to make something
similar to a screwdriver using solid aluminum rod for the handle and
1/16" brass rod as the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

Got a lathe? Failing that, you could lay the thing out by hand, carefully
centerpunch it, then put it in a drill press. I'm sure you already know
this, but with care, you'd be amazed at how precise you can be on *one*
small part. Especially if it is the second or third one you've attempted to
make. ;-)

KB

"Scott" wrote in message
...
I need to make a specialized tool and am looking for a way to drill a 1/16"
hole EXACTLY in the center of the end of a piece of say 1/2" of 3/4" solid
aluminum rod. In other words, I am trying to make something similar to a
screwdriver using solid aluminum rod for the handle and 1/16" brass rod as
the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

Got a lathe? Failing that, you could lay the thing out by hand, carefully
centerpunch it, then put it in a drill press

If you can, spin the part, not the bit.

Q

Take the part down to your local engineering shop, should cost about a
six-pack to drill both ends.

Hope this helps,
Peter

"Scott" wrote in message
...
I need to make a specialized tool and am looking for a way to drill a
1/16" hole EXACTLY in the center of the end of a piece of say 1/2" of
3/4" solid aluminum rod. In other words, I am trying to make something
similar to a screwdriver using solid aluminum rod for the handle and
1/16" brass rod as the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

You need a centering head square---http://www.wttool.com/p/1279-0006-----
put end of rod in Vee, scribe line using center blade, --rotate 90deg, scribe
again, intersection of scribed lines is center of circle...QED
Kyle Boatright wrote:

Got a lathe? Failing that, you could lay the thing out by hand, carefully
centerpunch it, then put it in a drill press. I'm sure you already know
this, but with care, you'd be amazed at how precise you can be on *one*
small part. Especially if it is the second or third one you've attempted to
make. ;-)

KB

"Scott" wrote in message
...
I need to make a specialized tool and am looking for a way to drill a 1/16"
hole EXACTLY in the center of the end of a piece of say 1/2" of 3/4" solid
aluminum rod. In other words, I am trying to make something similar to a
screwdriver using solid aluminum rod for the handle and 1/16" brass rod as
the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

"Scott" wrote in message
...
I need to make a specialized tool and am looking for a way to drill a 1/16"
hole EXACTLY in the center of the end of a piece of say 1/2" of 3/4" solid
aluminum rod. In other words, I am trying to make something similar to a
screwdriver using solid aluminum rod for the handle and 1/16" brass rod as
the blade.

Scott............

This may sound a bit backwards, but start with a hole and center the
aluminum around the hole.

In other words, first drill a hole in an oversized piece of rod. Try to get
it in the middle, but don't be too anal about it - just keep it straight,
not curved like a dull bit will tend to do. Either a drill press or a lathe
will work for this operation.

Then put the rod in a lathe, between centers, and drive it with a "dog".
Don't use a chuck. Turn the outside to the desired diameter. Now the outside
and the inside will be perfectly concentric. Saw off the butt end where the
dog clamped the rod to spin it. Violá . . .or Violin . . .or Viagrá.

Rich S.

Scott wrote ...
I need to make a specialized tool and am looking for a way to drill a
1/16" hole EXACTLY in the center of the end of a piece of say 1/2" of
3/4" solid aluminum rod. ...



Can't be done. Not "EXACTLY" anyway. If somebody hands you one
that's "exactly" dead nuts center, they simply aren't using a fine
enough means of measuring. So pick your tolerance, .005", .001",
..0005", .0001", a nanometer, an angstrom, a yoctometer, whatever.

If something within a few thousandths is sufficiently accurate, a
drill press alone will do the job. Trick is to make a one-time custom
fit vise in situ.

Take two chunks of similar dimension hardwood, say 1x2 oak. Screw
them together with a couple slips of paper between them. Don't use
bolts, only screws. Lay the assembly on the drill press table with
the seam & paper standing vertically, directly under the center of a
tiny drill bit (as close as you can eyeball it anyway). Clamp the
rear hardwood block to the drill table. Drill a 3/4" hole down
through the seam. Half of the hole will be in each piece of wood.
Leave the rear block clamped to the table while you partially unscrew
the front block from it. Remove the remnants of the paper spacer.
Put a little powdered rosin in the two halves of the hole (get a rosin
bag at a sporting goods store). Drop your aluminum stock in the hole
you just drilled & screw the front block back in place. You've now
clamped your stock in a hole that's pretty damn close to perfectly
centered under your drill chuck. Drill it to find out just how close.

Daniel

"Kyle Boatright" wrote in message ...
Got a lathe? Failing that, you could lay the thing out by hand, carefully
centerpunch it, then put it in a drill press. I'm sure you already know
this, but with care, you'd be amazed at how precise you can be on *one*
small part. Especially if it is the second or third one you've attempted to
make. ;-)

KB

"Scott" wrote in message
...
I need to make a specialized tool and am looking for a way to drill a 1/16"
hole EXACTLY in the center of the end of a piece of say 1/2" of 3/4" solid
aluminum rod. In other words, I am trying to make something similar to a
screwdriver using solid aluminum rod for the handle and 1/16" brass rod as
the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

Old mechanics saying: It ain't hard to make one piece alike, the
problem is making two alike.

Harry K

On Sat, 16 Oct 2004 11:52:02 +0000, Scott
wrote:

I need to make a specialized tool and am looking for a way to drill a
1/16" hole EXACTLY in the center of the end of a piece of say 1/2" of
3/4" solid aluminum rod. In other words, I am trying to make something
similar to a screwdriver using solid aluminum rod for the handle and
1/16" brass rod as the blade.

I dunno how exact you mean when you say exact, but this summer I built
a "C-Frame" riveting/dimpling tool and had to drill a 3/16" hole in
the "exact" center of a 5/8" rod. I accomplished this by finding a
piece of 1" or so round steel, clamping it in my drill press vise and
then clamping the vise to the drill press table. I first drilled a
3/16" hole completely through the 1" round steel (approx 2.5" long) as
close to centered as I could (non critical), and then chucked a 5/8"
bit in my drill press. Taking care to keep the alignment the same, I
then drilled about halfway down the first hole with the 5/8" bit to
make a drill guide.

I clamped the 5/8" rod in a vise, and placed the guide over it. Then
took the 3/16" bit in a hand drill and drilled into the rod using the
guide to center it.

It isn't as exact as using a lathe would have gotten, but it is more
than good enough for the task at hand especially considering that I
dont *have* a lathe. A picture of the C-frame tool (before paint and
sandblast) can be found he

http://www.rawlinsbrothers.org/bhfaq/imptool.html

It didn't occur to me to take a picture of the drilling guide but it
should be fairly self explanatory.


================================================== ==
Del Rawlins--
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/
Remove _kills_spammers_ to reply

Hey Kyle,
Well, I have zero experience on a lathe, so THAT's out

Actually, after my post and while having breakfast and COFFEE with
fellow EAAers, I thought of a way to do it. What if I had a piece of
square steel tube and put the round rod inside (as long as it's a snug
fit by wrapping layers of tape around the rod if necessary) and drew
lines across from opposite corners of the steel tube. That should put
the interesecting lines at the center of the aluminum rod.

I hope to get it on the first try

--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

Kyle Boatright wrote:
Got a lathe? Failing that, you could lay the thing out by hand, carefully
centerpunch it, then put it in a drill press. I'm sure you already know
this, but with care, you'd be amazed at how precise you can be on *one*
small part. Especially if it is the second or third one you've attempted to
make. ;-)

KB

"Scott" wrote in message
...

I need to make a specialized tool and am looking for a way to drill a 1/16"
hole EXACTLY in the center of the end of a piece of say 1/2" of 3/4" solid
aluminum rod. In other words, I am trying to make something similar to a
screwdriver using solid aluminum rod for the handle and 1/16" brass rod as
the blade.


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die