For those of us without cnc lathes, or right-angle heads, drilling/tapping
long stuff axially can be a real pain -- well, at least for hack matchinists
such as myself, and effing morons like jb.
Even with cnc lathes, iffin you don't have live tooling, a non-spinning
drill presents real problems, at least for me, ito chip evacuation, as well
as adequate coolant.
Thus, I like to do as many of these tasks on a vmc as I can.
A BP (and some drill presses) allows you to hang long stuff over the side,
but this is its own pita.
I have found a way to axially drill/tap the ends of long material pretty
accurately, up to mebbe 20" long, in a vmc.
The Fadal has a stock Z of about 19", *plus* 4" travel above the tool
carousel (machine Z0), for a total of 23".
However, a short tool holder + a stubby drill or tap subtracts at least 3"
from this, thus the 20" limit.
Now, I mount a collet chuck on a frame made from 1x3 alum (I inherited about
1500 lbs of this, in 3' lengths -- goodgawd), with the vertical members
being quickly unboltable, for various heights.
The bottom horizontal member is also interchangeable, for attaching directly
to the table, or in a single vise, or "half off" a vise (for rod clearance
clear down to the table), or between two vises. The horizontal alum of
course need a hole in line with the collet chuck barrel.
Now, the collet chuck can be positioned in height so that the minimum amount
of material protrudes.
Natcherly, the higher the collet chuck, the less rigid the setup will be,
but for drilling/tapping and lite facing etc, this is not really an issue,
and 1x3 alum is plenty strong.
The other way to go about this is to mount one of them big-assed 90's to the
table, plus a fixture, or even the collet chuck itself.
But the above system is a lot more convenient, and versatile, given its
vise-compatibility. And, can also be used on a BP, as well.
I have a ways to go before completely finishing this, as I've been displaced
from le fadal for a while, but it looks very promising.
Drilling/tapping on a manual lathe is actually pretty neat, but unless you
are well set up on hardinge-type stuff, it's a bear for anything approaching
And even with the hardinge secondary stuff, deep tapped holes are not the
swiftest, esp. in tough material.
Iny other idears?
14 years ago