Hi,

I've never used a DRO on a lathe, but often used a dial indicator on
the ways.

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

Is the third axis worthwhile-- given extra cost and additional hassles
to install?



Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"Spehro Pefhany" wrote in message
...

Hi,

I've never used a DRO on a lathe, but often used a dial indicator on
the ways.

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

Is the third axis worthwhile-- given extra cost and additional hassles
to install?


no

Spehro Pefhany fired this volley in
:

Is the third axis worthwhile-- given extra cost and additional hassles
to install?

It's a BIG hassle to install. For 99% of everything I do, I use only the
two axes, X and Z. It's fairly easy to do the trig to figure out what
moving the compound will do to the other two positions, if you really
need to figure it.

My DRO will 'compound' the compound and Z axis, but won't figure the
numbers for X at the same time. To do so would require an encoder on the
compound swivel and some pretty sophisticated algorithms I don't think
the average DRO possesses.

So it's really not worth the hassle to add the third additive axis.

LLoyd

On Wed, 25 Jan 2012 21:29:56 -0500, Spehro Pefhany
wrote:


Hi,

I've never used a DRO on a lathe, but often used a dial indicator on
the ways.

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

Is the third axis worthwhile-- given extra cost and additional hassles
to install?

Assuming you're referring to the compound, most people would say "no."
When Mitutoyo was first selling its retrofit scales for engine lathes
I had a discussion with their technicians about the subject, since I
was thinking about doing it myself (I didn't; I decided to be a
traditionalist/hobbyist). They said that most people would find it to
be of little benefit.

I'm sure that some people use the compound in a way that they would
benefit from it, but the consensus was that most would not.

Now someone will come along and tell us all the ways he uses a scale
on his compound. d8-)

--
Ed Huntress





Best regards,
Spehro Pefhany

Spehro Pefhany fired this volley in
:

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

BTW... I went with magnetic scales, and am quite happy with the product.

DROPROS.com

LLoyd

On Wed, 25 Jan 2012 21:42:18 -0500, the renowned Ed Huntress
wrote:

On Wed, 25 Jan 2012 21:29:56 -0500, Spehro Pefhany
wrote:


Hi,

I've never used a DRO on a lathe, but often used a dial indicator on
the ways.

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

Is the third axis worthwhile-- given extra cost and additional hassles
to install?

Assuming you're referring to the compound, most people would say "no."
When Mitutoyo was first selling its retrofit scales for engine lathes
I had a discussion with their technicians about the subject, since I
was thinking about doing it myself (I didn't; I decided to be a
traditionalist/hobbyist). They said that most people would find it to
be of little benefit.

I'm sure that some people use the compound in a way that they would
benefit from it, but the consensus was that most would not.

Now someone will come along and tell us all the ways he uses a scale
on his compound. d8-)

So far, it's unanimous-- rare on forums.

Thanks, gentlemen, I think I've made my decision.. the 2-axis choice
is from a less worrisome local supplier, so I'll go that way.

Best regards,

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"Spehro Pefhany" wrote in message
...
On Wed, 25 Jan 2012 21:42:18 -0500, the renowned Ed Huntress
wrote:

On Wed, 25 Jan 2012 21:29:56 -0500, Spehro Pefhany
wrote:


Hi,

I've never used a DRO on a lathe, but often used a dial indicator on
the ways.

I'm thinking of adding a glass-scale (2 tenths resolution) DRO to at
least two axes.

Is the third axis worthwhile-- given extra cost and additional hassles
to install?

Assuming you're referring to the compound, most people would say "no."
When Mitutoyo was first selling its retrofit scales for engine lathes
I had a discussion with their technicians about the subject, since I
was thinking about doing it myself (I didn't; I decided to be a
traditionalist/hobbyist). They said that most people would find it to
be of little benefit.

I'm sure that some people use the compound in a way that they would
benefit from it, but the consensus was that most would not.

Now someone will come along and tell us all the ways he uses a scale
on his compound. d8-)

So far, it's unanimous-- rare on forums.

Thanks, gentlemen, I think I've made my decision.. the 2-axis choice
is from a less worrisome local supplier, so I'll go that way.



Its not needed on the compound...

For threading, set the compound dial to a convenient zero point then use the
cross slide and touch the work....now, set the cross slide dial not ot zero,
but to the double depth amount instead....( or in your case, set zero, move
off and dial in the double depth amoount and reset zero again ) now, back
off on the compound and then you can take all of your passes with the cross
slide always at zero on the dial, moving the compound inward by .005 or so
each pass till you get to zero on both your dials.

"Spehro Pefhany" wrote in message
...

snip
Thanks, gentlemen, I think I've made my decision.. the 2-axis choice
is from a less worrisome local supplier, so I'll go that way.

Best regards,

Best regards,
Spehro Pefhany
--

There probably isn't much useful data to come from compound DRO unless you
have a 4th rotary axis for compound angle and tool geometry figured in.

RogerN