Joseph Gwinn wrote:
In article ,
David Billington wrote:


Tom Gardner wrote:

My "UNIQ" 2-axis DRO display has failed. The vendor says the power supply
is bad and can't get a replacement. They have offered a direct replacement
"UNIQ" for $295 or a "JENIX" display for $200.

I have asked them to return the unit. Does anyone know anything about
these? Would the PS be fairly easy to repair? I'll know more when I get
it
back and apart.




My neighbour has a Uniq DRO IIRC and I'll enquire about whether he has
any info regarding the power supply. We had noted a software flaw in one
routine where it defaulted to metric regardless of the setting but that
could be lived with.

I have a Newall DRO and it failed due to what was likely a vibration
induced failure in the power supply chip legs. The DRO display was
mounted in a common manner on the headstock of the lathe and it failed
when doing an operation which caused chatter which I rarely allow.
Talking with a tech at Newall he mentioned that failure was common which
didn't impress me for something which should have been designed for an
industrial situation. I had looked for such problems but didn't look in
that detail, next time I will.


A chattering lathe has prodigious vibration power, a major fraction of
the motor output power, and if the DRO is rigidly attached to the
headstock, I bet it got quite the shaking, to a degree that very few
industrial (versus military) designs can handle. Especially if the
chatter frequency happened to coincide with a mechanical resonance in
the DRO.

If the DRO is instead attached to the cabinet or splash shield, it won't
get quite the shaking, and may live longer.

Joe Gwinn

You may be right but I rarely allow chatter and it was an odd occasion
that it happened, I was cutting short lengths of small tube about 6mm in
diameter with a slitting saw in the spindle and it excited the system on
my Harrison M300 so the lathe was certainly not struggling. The DRO is
mounted on an arm extending forward from a pillar mounted to the back of
the headstock as is fairly common. I compare the Newall against the Sony
Millman on my BP which has never given me a problem in twice as many
years of ownership. The Sony is fitted to an arm fitted the the column
on the BP and it more regularly sees vibrations due to cuts compared to
the Newall on the Harrison. The Sony has never exhibited any problems or
software flaws whereas the Newall has shown several software flaws such
as trashing of the linear error compensation values and losing the
setting for what type of hardware it is. The hardware type is exhibited
by it not knowing about tool offsets which shows it has had its hardware
type reset or corrupted so it doesn't know whether it is a lathe or mill
DRO, I was provided with the procedure to reset those settings if they
became corrupted.