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Hooray! Fixed!

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et...@whidbey.com

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Dec 3, 2018, 7:35:54 PM12/3/18
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I live on an island and it is hard to get CNC repair people out to
look at the machines. So I fix 'em myself.
The Miyano lathe developed a problem last week. It refused to
execute one particular M code, the spindle speed could no longer be
controlled in a program, the jog spindle speed dial now controlled
speed even in auto mode when it should not, and the "used up" alarm
came on after every part.
I called FANUC and they figured it was a particular circuit board.
I found one on eBay and ordered it. But it's a week and a half away.
I checked all the diagnostic parameters and everthing was fine.
Then this afternoon I checked the regular parameters and one had
changed. A parameter who's function is not listed in the book so I
didn't know what it did. But I had written down all the parameters
when I bought the machine, they are mostly 8 digits long, just ones
and zeros, but some are otherwise, such as backlash amounts, which are
entered as some multiple of one ten thousandth of an inch. The machine
was used when I bought it so some of the original parameters could
have changed, like backlash. And I have changed parameters too in
order to get the machine to do things it did not do when I bought it.
So I got into the back of the machine, where all the high voltage
is, along with the computer, opened up the computer enclosure and
flipped the parameter change switch. Then I used the control keyboard
to change the parameter back to where it was, got back behind the
lathe and flipped the parameter switch, cleared the alarm that happens
whenever a parameter is changed, and the machine now works great.
All I did was change a 0 back to a 1. I wonder how the damn
parameter changed in the first place?
Anyway, I am really happy now. Really happy. I mean REALLY HAPPY!
Eric

Rheilly Phoull

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Dec 3, 2018, 8:14:57 PM12/3/18
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Yeah, sorta like rule 1 "Reboot" :-)

Dave Platt

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Dec 3, 2018, 8:15:45 PM12/3/18
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In article <v6ib0eprmjiaikh9i...@4ax.com>,
<et...@whidbey.com> wrote:
> A parameter who's function is not listed in the book so I
>didn't know what it did. But I had written down all the parameters
>when I bought the machine

Very wise!

> All I did was change a 0 back to a 1. I wonder how the damn
>parameter changed in the first place?

Might have been a bit flip in memory somewhere (cosmic ray, bad IC,
etc.).

Or, is possible to change those parameters under software control that
doesn't require the manual "parameter unlock" switch? A garbled
command sent to the device - even a one-character error in
transmission - might have "silently" changed a parameter in an
unexpected way.

Or, maybe, this parameter was changed as a side-effect of some other
(legal and reasonable) command?

John Robertson

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Dec 3, 2018, 8:17:26 PM12/3/18
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If this machine's computer uses a battery backup CMOS RAM then your
problems could be just starting. If a lithium battery, then change it
with the power on so you don't loose any settings (and very clever of
you to record that info!), if Ni-Cad then watch out for alkaline leakage
and again, replace with power on using an isolated tip soldering iron
(batter or propane is easiest) if it requires unsoldering. Extend the
wiring to it so it is away from any electronics...

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

et...@whidbey.com

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Dec 3, 2018, 8:29:35 PM12/3/18
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As far as I know there is no way, oiher than flipping the parameter
switch, to change parameters. And besides, it worked one day and then
whenturned on the next day did not.
Eric

Terry Schwartz

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Dec 3, 2018, 8:31:20 PM12/3/18
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Just like early Bally SS machines....

et...@whidbey.com

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Dec 3, 2018, 8:33:17 PM12/3/18
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On Mon, 3 Dec 2018 17:17:18 -0800, John Robertson <sp...@flippers.com>
wrote:
The machine does have battery backup. An alarm condition tells you
when it is time to replace batteries. FANUC controls are very good at
telling you when it is time to change batteries. Nevertheless I always
change batteries on a schedule so the alarm has only happened once,
shortly after I bought the machine.
Eric

John Robertson

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Dec 3, 2018, 8:44:32 PM12/3/18
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On 2018/12/03 5:31 PM, Terry Schwartz wrote:
> Just like early Bally SS machines....
>

Game Plan MPUs are worse for battery self-destruction. The battery is on
the side of the board, not the bottom, so the eating is good (for the
alkaline)!

Ralph Mowery

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Dec 3, 2018, 11:21:17 PM12/3/18
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In article <v6ib0eprmjiaikh9i...@4ax.com>,
et...@whidbey.com says...
> whenever a parameter is changed, and the machine now works great.
> All I did was change a 0 back to a 1. I wonder how the damn
> parameter changed in the first place?
> Anyway, I am really happy now. Really happy. I mean REALLY HAPPY!
> Eric
>
>

Where I worked we had hundreds of devices that had microprocessors in
them. For no reason we could tell every once and a while one might do
something strange and would have to be reset. This may only happen once
a year or so.

When memory chips first came out, it was said that the coverings of them
might emit an alpha partical and flip a bit.

et...@whidbey.com

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Dec 4, 2018, 12:08:44 PM12/4/18
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I figure it was a cosmic ray. Maybe my machine has a nuetrino detector
in it! 1 detection in many years fits the bill. How many years I don't
know but the machine has been around a long time. I could wrap the
machine in lead to protect it but I don't have any two light years
thick pieces.
Eric

Fox's Mercantile

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Dec 4, 2018, 1:59:29 PM12/4/18
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On 12/4/18 11:15 AM, et...@whidbey.com wrote:
> I figure it was a cosmic ray.

When I was doing CNC repairs at Northrop Aircraft, I had
an odd problem with a Pratt and Whitney Starturn lathe.
They had these HUGE 3" x 18" helical wound resistors for
the spindle braking. Because of the current, the winding
wound bounce like a Slinky toy. Eventually breaking off
the ceramic nubs on the form. So when they'd apply the
spindle brake, the turns would short out and arc. Add
that to the crap job the machine installer did with the
grounding and you have a major problem.

So, one night, the operator is most of the way through
making a 6" diameter hydraulic coupling. The machine
forgot to recenter a boring bar and went to rapid retract.
Nice, but it pulled the part out of the chuck while it
was turning at a high rate of speed.
After making 5-6 full loops around the inside of the
safety cover, if finally found the sweet spot, exploded
the glass and took off past the operators head and through
the wall behind him.

On the other side of the wall, it found a 36" Blanchard
grinder and hit the wheel, breaking it. The next thing to
happen was a seriously off balanced grinder trying to hop
across the shop until it ripped it's wiring apart.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

jurb...@gmail.com

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Dec 7, 2018, 6:50:44 AM12/7/18
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On Tuesday, December 4, 2018 at 1:59:29 PM UTC-5, Fox's Mercantile wrote:
You have all the fun.
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