On 2009-03-10, wrote:
I am a beginner

I have the Sieg X2. The Cummins version. I want to make the Z-axis
as square to the table as possible and I don't know how. I want to
drill very straight holes.

Bear in mind that a drill *won't* drill very straight holes.
The hole tends to wander as the hole gets deeper.

A reamer following an undersized hole can do better.

Best is boring -- which means a boring head in the spindle of
the mill if you don't have a lathe to do it on. And this is more of a
problem with smaller holes -- finding a boring bar which will work in
the rough hole which you drilled is more difficult, and the drill bit
will wander more during the rough drilling.

I see that the head can be adjusted side by side. By loosing the big
nut in back. How do I make sure this is as straight as possible? I
have used a square and eyeballed it. How would I use a test indicator
or Dial indicator to make it more accurate?

A test indicator mounted on something held in the spindle so the
indicator is several inches from the centerline of the spindle, Swing
the indicator to the left and to the right and compare the readings.
Adjust until both readings are as close to the same as you can manage.

Is it possible to adjust the squareness of the head front and back?
Is there adjustments for this?

Not a designed in one on the Sieg as far as I know (I don't have
one, so I can't be sure), but you could loosen the bolts holding it to
the base casting, and add shim stock (available in various thicknesses)
until your front to back measurements with the same setup described
above for measuring the side to side error is to a minimum difference.

How square front and back do the Sieg X2 mills come out of the box?

No idea. Measure to find out using the above technique.

How would they compare to a quality drill press?

They *should* be better than a typical home drill press, but
probably no better than a radial arm industrial drill press for serious
work. (But the odds of having the power needed to run one of those are
pretty slim in a home shop -- or the space to mount one -- or the
ceiling height. :-)

I have collets for the bits I need to use. But how accurate is the
standard chuck that comes with the mill?

Probably pretty poor. Measure the runout close to the chuck and
at some distance from the chuck with a hardened drill blank or other
test rod.

A good drill chuck (such as an Albrecht or the ball bearing
Jacobs keyless which is a semi-clone of the Albrecht) on a *good* arbor
can be quite good.

And I hope that you know to *not* try using the chuck for
holding milling cutters? They don't grip well on the hardened shanks of
the milling cutters.

There are Albrecht drill chucks available on R8 spindles (and
some others as well) which have diamond impregnated jaws for gripping
hardened shanks -- but you may be getting up to a serious percentage of
the price of your machine for one of those. :-)

Good Luck,
DoN.

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