WCS and tool offset question - please help!

[ecdez]

First off, I apologize in advance if this is a stupid question but it's driving me nuts.

The machine is a Hardinge Accuslide and is the subject of this thread - viewtopic.php?f=60&t=5043

I posted a similar question in the timeline in that thread but it was a holiday so I'm guessing it got missed.

I've spent that last week reading the manual and watching all the videos I can find and thought I had a handle on it but just can't seem to nail it. Here's the issue.

Prior to all of this the axis were dialed in and calibrated.

Trying to setup tool offsets. Go to WCS1, take a skim cut and measure the diameter enter it as X dimension. 0.927"

Follow instructions and set the tool offset for tool #1

At this point X0 should be the center stock right? So I Jog the tool to X0 and it blows right to the other side of the part. The center of the part actually falls right at 0.4635 or 1/2 of the diameter.

Confused by this I went back to my skim cut and move the x axis 1" away just to verify that I'm actually moving an inch and it did.

What am I doing wrong!? Is it a setting pr something?


I'm sorry if I'm being needy or elementary but I'm only a few short steps away from having a usable machine.

My apologies if my question rambles a little. My father passed away yesterday and I'm just out here looking for a distraction and hoping to accomplish something.



current report

report_0CB2B7D683E2-1113203964_2021-01-04_14-25-13.zip

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[cnc_smith]

What am I doing wrong!? Is it a setting pr something?


I'm sorry if I'm being needy or elementary but I'm only a few short steps away from having a usable machine.

My apologies if my question rambles a little. My father passed away yesterday and I'm just out here looking for a distraction and hoping to accomplish something.

My condolence for the loss of your father.

Remember that the lathe is in Diameter mode so the distance that is measured with your rule should be a radius value of 1/2'" instead of 1.00".
So when you set up your turns ratio if you used a dial indicator and told the machine to move 1 inch on the DRO the Dial indicator will only show 1/2". It appears that your motor revs/in is wrong.

[cncsnw]

Echoing what Dana said:

When you 'move the axis 1" away', and the DRO display changes from 0.9270 to 1.9270, did the X axis actually move 1"? I.e. did you go from the tool touching the 0.927" diameter, to having one inch of daylight between the tool and the 0.927" diameter?

If so, then your X axis turns ratio is not set correctly.

On a lathe control, a move that changes the displayed DRO position by one inch, should move the cross-slide only one half inch. If you move the cross-slide one inch, the DRO position should change by two inches. This is because commanded and displayed X positions on a lathe control represent part diameter, not part radius.

If your tool is touching a 0.927" diameter, then the tool tip is 0.4635" away from centerline. If you move the cross-slide back one inch (of actual distance), then the tool tip would be 1.4635" away from centerline, where it would be touching/cutting a 2.927" diameter. Therefore at that place, the DRO should read X+2.9270.

[ecdez]

Many thanks to both of you for your responses. I actually had the machine set up that way about two weeks ago but convinced myself it was wrong. I've retrofitted two mills but this lathe is kicking my butt. It's just different enough to confuse me to the point of frustration. Maybe the other personal stuff going on at the same time is contributing.

I made the change and got the gang tool block dialed in so hopefully I can make a test run tomorrow. Thanks again, I appreciate the quick and detailed responses.