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Told we didn't make any money.

Even once everything besides cycle time has been accounted for, getting an accurate cycle time isn't a simple matter of cut inches times feed rates. You need to accurately predict the accelerations, rapid moves, toolchanges, spindle ramp-up and down, etc. I have two machines of the same make and model, same RPM spindle, but different year, and their cycle times differ by a few percent on the exact same programs. That said, for many low quantity jobs, cycle time is the smaller share of the job's time.
 
Even once everything besides cycle time has been accounted for, getting an accurate cycle time isn't a simple matter of cut inches times feed rates. You need to accurately predict the accelerations, rapid moves, toolchanges, spindle ramp-up and down, etc. I have two machines of the same make and model, same RPM spindle, but different year, and their cycle times differ by a few percent on the exact same programs. That said, for many low quantity jobs, cycle time is the smaller share of the job's time.
Our lathes have barfeeders, so we have to account for the load new bar time as well, also they are Haas so you never know how that bar change is going to go, it is a gamble. There should be a checkbox on all forms and spread sheets to account for Haas.
 
Our lathes have barfeeders, so we have to account for the load new bar time as well, also they are Haas so you never know how that bar change is going to go, it is a gamble. There should be a checkbox on all forms and spread sheets to account for Haas.

How bad can you mess up a bar change?
 
How bad can you mess up a bar change?
Because they are servo fed and can not be pushed to a stop, we get all kinds of short push, long push, and in between. Sometimes the push rod won't load correctly and jumps off the pins and wraps around the tray ( the small push rod not the larger one). Then I got to straighten it out in a vise, realign the push rod, and start again. It's why I have multiple push rods made up and waiting. One fucks up I change it out, align the new one and straighten the other while the job is running.
 
Because they are servo fed and can not be pushed to a stop, we get all kinds of short push, long push, and in between. Sometimes the push rod won't load correctly and jumps off the pins and wraps around the tray ( the small push rod not the larger one). Then I got to straighten it out in a vise, realign the push rod, and start again. It's why I have multiple push rods made up and waiting. One fucks up I change it out, align the new one and straighten the other while the job is running.

What kind of servo are they using that's that unreliable? A Lil Tykes My First CNC? :D
 
Because they are servo fed and can not be pushed to a stop, we get all kinds of short push, long push, and in between.
I can see the pushrod bending. That's a mechanical failure. Are you also saying the servo doesn't push repeatably? My understanding is the bar feeder is just another axis, driven like any other servo on the machine, similar motor, encoders, mocon feedback, etc. I can't understand how it could mess that up. Can you share any other wisdom?
 
I can see the pushrod bending. That's a mechanical failure. Are you also saying the servo doesn't push repeatably? My understanding is the bar feeder is just another axis, driven like any other servo on the machine, similar motor, encoders, mocon feedback, etc. I can't understand how it could mess that up. Can you share any other wisdom?
Yes, I am saying the barfeeder does not repeat. Especially on a double push. It don't help that the machining manager before me did not take care of them either. No chamfers, bar not cleaned. It damaged some of the liners. I got what metal shavings out of them that I could, but they really need to be replaced. We have 4of the Haas barfeeders and they are inconsistent at best. Best wisdom I can give is not buy Haas barfeeders. Buy LMS or any other dependable barfeeder that can push to a stop.
 
But it's a servo. How does it misfeed? The encoder should know where it is or isn't. Is there some safety clutch that's letting go and allowing the servo to reach position without truly getting there?
 
But it's a servo. How does it misfeed? The encoder should know where it is or isn't. Is there some safety clutch that's letting go and allowing the servo to reach position without truly getting there?
I'm not going to BS you and tell you I know why or how. It makes no sense to me either. I have reset and set back up from scratch, set all the parameters, slowed it down, cleaned it out, took it to dinner and it still is not consistent. Like I said the double pushes are the worse. I wish I knew how to fix it, but I don't.
 
I'm not going to BS you and tell you I know why or how. It makes no sense to me either. I have reset and set back up from scratch, set all the parameters, slowed it down, cleaned it out, took it to dinner and it still is not consistent. Like I said the double pushes are the worse. I wish I knew how to fix it, but I don't.
Are you sure it's a servo and not a stepper motor ? A cheaper stepper I could see Haas using for that. Worn and dirty parts could make a stepper lose steps and position easily.
 
I'm not going to BS you and tell you I know why or how. It makes no sense to me either. I have reset and set back up from scratch, set all the parameters, slowed it down, cleaned it out, took it to dinner and it still is not consistent. Like I said the double pushes are the worse. I wish I knew how to fix it, but I don't.
Your problem deserves its own thread. I bet some of these Dudes could help fix that.
 








 
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