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haas lathe VCS face bug?

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Plastic
Joined
May 9, 2016
hi, i've got a TL-1 lathe and i think i've found a bug in the VPS face operation. i'm wondering if anyone can confirm this, or if i'm doing something stupid.

here's what's happening: the FACE_STOCK setting is described as "Enter the total amount of STOCK to remove from the FACE of the part" and i'm entering 0.04 and when i run it, it will start the operation 0.04" in front of the actual face of the part.

it then does face passes in the air, and then ends the operation before it actually reaches the real face of the part. and yes, i've triple checked the Z-face offset of the part. i've rebooted, and tried again, and it just seems to be confused about what it's doing.

i thought to put negative 0.04" in the FACE_STOCK variable, but it won't let me.

again, am i doing something stupid or is this a bug?

haasbug.jpg
 
the behavior you're describing and the diagram in your screenshot match up, note the origin. that's not a bug. the template may be awkward, sure.

change your z offset by -.04 and re-run. your bar should clean up, and change the offset back to have the tool perfectly at zero.
 
the behavior you're describing and the diagram in your screenshot match up, note the origin. that's not a bug. the template may be awkward, sure.

change your z offset by -.04 and re-run. your bar should clean up, and change the offset back to have the tool perfectly at zero.

so...what you're saying is that i should set the z-offset to where i want the finished face to be, not where the actual z-offset of the part is? i hear what you're saying, and i think that should work - but it sounds like the way the VPS face operation is setup is kinda stupid.

but thanks for sanity check. maybe not a bug, but just a stupid design.
 
I bet you're touching the face of the stock and entering it your G54 Z zero. You need to set it as Z 0.04.
 
Not for this bumpkin. 0 for me is the OTHER end. I hate working in negative numbers. Plus if you make your zero a spot on the fixture or a stop in the jaws, you can actually find it.

No offense, but you need to get out of that mindset. Will not serve you well in the future.

Mike
 
I'm going to tell you my pet peeve about learning how to program a machine like that...

You have to learn how to converse with a stupid machines in stupid conversational canned quirks.
I much prefer to just write out in G-Code exactly how you want the machine to move.

No guessing whats going to happen is involved.

GO X 2.1 Z0 (moves machine to X2.1 Z0)
G1 X-.03 F.004 (machine feeds X to -.03 at a feed rate of .004)
G1 Z.01 ( moves tool .01 from work face)
G0 X2.1 ( rapids tool to X2.1)

Yes, its a couple extra lines to write, yes you need to think in G-code...but you read it and know exactly whats going to happen. Not hope, know.

Plus no stupid quirky moves the machine decides to put in.


My answer, Learn G-code, learn it once, you know it for all machines with some machine specific nuances...but its better then canned crap that asks a ton of stupidity and formulates a cut path , clearances etc.

I know, because thats how I started and while it was great as I was making parts, I had little control over them, heavier cut here, lighter there. If I had a problem the code meant little to me so I couldn't tweak or find problem...but had to get back into that conversational stuff again.

Next machine came in with straight G- Code. I started by programming it from the machine with conversational then bringing it over. But then I had two machines down. So it was program simple programs at the G-code machine. Soon I was writing more complex programs in less time then the other machine and they ran faster. ANd a huge benefit I could look at a program, and figure out what was wrong, how to tweak in so much less time.
It really doesn't take long to start thinking in G-code...
 
In almost any situation, mill or lathe, the finish face surface on a part IS Z zero.

Yes. Not to confuse the matter, but if (assuming conversational) you were milling a part it is the same way for facing. If you touched the top of the part/stock and called that Z0, then told it you wanted to face .04 off, it would start at Z.040 and move to Z0 and make the cut. Which cuts nothing because you set Z0 as Z0. For both examples, you want to touch the face then offset your workshift (NOT the tool) a certain amount so you actually have some stock on the Z positive side... clear as mud? :leaving:
 
... clear as mud? :leaving:
And wrong, as well :D

Okay, not wrong, just "the other method". There's been the two ways to approach this since the beginning. Some of us like positive numbers from a known datum, the rest of you fall for the "easy to touch off" method.

Hop up a post or two and read SIM's description. For some people, telling the machine exactly where to go is the hot ticket, and this "oooh, you have to be modern !" shit (aka a slave to the stupid Fanuc method) is nonsense. It's not modern, it's backwards and upside-down. You want to do it, go ahead but it's not easier or better.

Screw the "work shift", make the datum 0 in the first place.
 
And wrong, as well :D

Okay, not wrong, just "the other method". There's been the two ways to approach this since the beginning. Some of us like positive numbers from a known datum, the rest of you fall for the "easy to touch off" method.

Hop up a post or two and read SIM's description. For some people, telling the machine exactly where to go is the hot ticket, and this "oooh, you have to be modern !" shit (aka a slave to the stupid Fanuc method) is nonsense. It's not modern, it's backwards and upside-down. You want to do it, go ahead but it's not easier or better.

Screw the "work shift", make the datum 0 in the first place.

1) I specifically said "if using conversational"
2) G code/fingercam/conversational are sort of irrelevant in how you touch off your part in the machine, it is just some of the terminology is confusing in some conversational systems.
3) There is no "easy to touch off" IMO, it's a freaking pickup point, no more no less. You want to program and use machine zero as zero, go for it, you want to have zero be at the corner of your vise and plus 5" in Z, knock yourself out. As long as you (or setup peeps) know where to set zero it doesn't really matter. Might not make sense to some, but it's your machine.
 
Might not make sense to some, but it's your machine.
It's the traditional method, actually ... Wait until you program a machine that doesn't have offsets, what're ya gonna do then, kid ? :D

I found it annoying that someone (not you) would be blathering about how you can't program a lathe except via the fucked-up Fanuc method. Sorry if you got dragged in but ... programming from midair is pessimum, to me. And making your zero be something that changes all over the place, well ... but it's your machine :D
 








 
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