Fanuc offsets off

I had an odd one just happen.

A job that was pronounced ready to roll at end of the day yesterday does not run today. I have a simple 2 tool lathe job set-up. I got everything dialed in and called it a day.

Today I fire up the machine and go to run the first part and now my tools are waaaaayyy off in both X and Z. They both seem to be off a similar amount. About .625" roughly by eye. If I had let it rip I would have had a pretty good wreck on my hands.

I brought T1 down to see how that matched up and that was also off. T1 has not changed in over a year. I used T1 to machine the fixture and all was well.


I restarted the machine twice to see if it was a crazy alignment problem.
Same result.

Oddly I can bring an empty boring socket down to X0 in machine coordinates and it is visually aligned.

Any idea what the hell happened here and how to I get it back?

The machine is a Hardinge Talent 852 with a Fancu OiTc control.


I'm stumped.

ARB said:

I had an odd one just happen.

A job that was pronounced ready to roll at end of the day yesterday does not run today. I have a simple 2 tool lathe job set-up. I got everything dialed in and called it a day.

Today I fire up the machine and go to run the first part and now my tools are waaaaayyy off in both X and Z. They both seem to be off a similar amount. About .625" roughly by eye. If I had let it rip I would have had a pretty good wreck on my hands.

I brought T1 down to see how that matched up and that was also off. T1 has not changed in over a year. I used T1 to machine the fixture and all was well.


I restarted the machine twice to see if it was a crazy alignment problem.
Same result.

Oddly I can bring an empty boring socket down to X0 in machine coordinates and it is visually aligned.

Any idea what the hell happened here and how to I get it back?

The machine is a Hardinge Talent 852 with a Fancu OiTc control.


I'm stumped.

Click to expand...

My bet is it's referenced off by 1 turn of the screws. Is it an absolute or incremental encoder machine?

Hopefully you figger it out and report back strait away!

I have a 16T that all of a sudden started having Z axis ghosts. Scrapped the last part of a 30 pc run a few weeks ago. A new 16" D blank aint cheap, and I have seven 19" blanks to run this weekend now.

Not even HOMED the machine in the mean time either... ???

Maybe if you figger out what's up with yours, it will fix mine too!


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Think Snow Eh!
Ox

I was thinking the One rev on the screw deal. Any idea what parameter tells the screw pitch? I looked through the parameter manual for a while but gave up when my eyeballs started bleeding.

The odd thing is I seldom make a comp adjustment on this machine. All the finish tools run with PCD inserts and I always fire up a new program and things are spot on. Once in a blue moon I need to comp a thread tool a bit.


On a brighter note Ox. We are getting some snot I mean snow tonight.

Referencing off by one turn of the screw seems reasonable for one axis, but both axes?

QB

If the machine hasn't been ran much, could be sticky reference switches....(provided it's incremental encoders)

This is one of fanuc greatness

Question Boy said:

Referencing off by one turn of the screw seems reasonable for one axis, but both axes?

QB

Click to expand...

My thoughts 'zactly....



Arby - from the sounds of it - you don't have many progs in the library eh?

I know that I have said it many times before, but I have TWO diff Fanucs that have gotten funny doo to too full'a libraries. One is continually that way - the other hasn't done it in yrs now, even with lots of progs in it aggin.

Never seen this issue tho...






... well - the library is pretty full in my 16T that just started acting up....






We had heavy rain here all afternoon.
Got all my deliveries done before it let loose.
However I had to load and strap down my propane gas tanks for the forktrucks during 35* rain.

Our daytime rain could be your overnight slush....


--------------

If it dried back out once we would be crying about a drought.
Never happy with the weather....
Ox

I am not too high on program numbers but.... I am 2 higher than I was.

The machine has been sitting for a little while....


Once I cobbled the offsets to make good parts all seems well and repeats.


I will keep an eagle on it for a while.

In other news my Brand Friggin new PCD insert lasted for about 5 parts.
I think I found an inclusion in the casting.


Oh Ox....It tis snowing right now.

Bud - let me tell yuh - I am one happy camper ratt about now!


Going into a 4 day weekend knowing that you have 5000# of 1045 to run through a machine with a known Z axis ghost with parts due on Monday - leaves a fella a bit uneasy....


However....



I found MY ghost!

Ended up being a tapered pin that holds the driven gear to the lead screw had FALLEN OUT!


At first when I seen it, I expected sheared. I push some good sized stuff with this heifer. A 3.500" insert drill would be the highest machining thrust, but I also when needing to seat a big part in the chuck, I will shove a tool up agginst a 2by and push on it and then release the chuck and reclose it. Occassionally we could have gotten a bit too much thrust on it one time, but haven't done that it a while, and the last part of a 30 pc run is when it appeared, so that didn't hardly make sence that it was from pushing on it.

But a sheared pin would catch here and there and would seem to make sence, but then I looked down in the url bath, and there she was - in all her glory .... one complete tapered pin, with no signs of molestation.

NOW - the job just requires that you line it up and shove it back in aggin.... well - 'cept for the fact that a tapered pin only goes in one di-rection. I know that it would seem like a 50/50 chance that when you git the gear spun around to a hole that it would be right ... but it is like hooking up 3-phase warrs. The rule book says 50/50, but unlike a bookworm, those of us that have actually hooked up several machines _ we know that the 50/50 rule only applies 50% of the time. The rest are just plain wrong. And of course mine was as well....

But now - I really don't see that pin comming out of that seat on her own accord aggin in my lifetime.


From the time that the ghost re-appeared tonight to the time the cause was found, the repair was done, case filled with url, and all Z offsets updated - couldn't'a been over an hr and a half on the outside. I guess THAT was my 50/50 on the other 50% of the time eh? FINALLY got one of those!


Good luck with your ghost there chumm!


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Think Snow Eh!
Ox

Good for you Ox. Always good to find a Ghosty.