On Wed, 03 Dec 2014 12:26:39 +0000, Chris J Dixon wrote:

Dave Plowman (News) wrote:

In article ,
Chris J Dixon wrote:
And that tends to be the problem with a drill stand. Sideways play.
To minimise that, you need a pillar drill where the chuck is
concentric with the pillar. Then it's just down to how well it is
made.

It is probably my lack of imagination, but I can't picture that
arrangement.

Sorry - not well described. On a pillar drill the chuck is concentric to
the moving pillar - whatever that is called - so any slop restricted to
play between that pillar and its housing. They usually have a method of
taking up any play too - although on many cheap ones this isn't well
made.

On a stand there is a housing to take the drill sliding up and down a
pillar and any pivoting on that translates into sideways slop at the
drill bit.

I think I can see what you are trying to say.

On a pillar drill, the motor assembly is supported by the pillar from
which the device takes its name. A separate drive shaft carries the
chuck, allowing it to be raised and lowered, and it is concentric with
this shaft, not the pillar.

Chris

Think this is what you are after

http://en.wikipedia.org/wiki/Quill_drive

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