Update commands with new part alignment

[operator1]

Top of tha mornin to ya!

Quick question that I thought I knew the answer to, but obviously do not...

When you create an alignment that already has features before it, what is this prompt asking exactly? I usually always press yes, but when I went to PCDMIS training, she instructed us to select "No". What will updating the commands do? Does it help or hurt?

T.I.A.

[Matthew D. Hoedeman]

This will ONLY pop-up when you have features/dimensions AFTER the alignment you are changing and it will only effect the features/dimensions AFTER the alignment.

What happens is this:

Say you typed in the wrong axis off value when you made the alignment. But, you didn't notice it when you did it. So, instead of typeing in 1205 for X, you typed in 1250 for the X offset. Well, for straight up/down checkes, you might not see that you screwed up. However, when you go to a check in the X axis, that 45mm of error will show up and it will be obvious to you that you messed up the alignment. Well, the 3-2-1 CAD=PART alignment has been set to that X value, you have programmed a point WITH the cad data and found the error. The aprt will check off 45mm, but it's not off, so you fix the alignment. Lets say the nominal for that point in the X axis is 1145. Now, you go back to the alignment and fix the 45mm mistake you made, but it asks you that question. IF you tell it YES to update, then the nominal for the point you programed will CHANGE by the amount you CHANGE the alignment and will thus no longer be on the cad data and it will still show 45mm off when you check it.

There is ONLY one instance I can think of when you want to tell it YES, CHANGE and that is when you change the manual alignment offsets after you have programmed the DCC alignment features.

Basically, ALWAYS TELL IT NO!

[Wingman]

WMS. I almost always say NO. Saying YES is good if I have forgotten to put in an alignment and I have programmed features that I want to be in the new alignment. Only works seamlessly when I catch it quickly. Basically, you need to know WHY you are saying YES. PC DMIS will change the nominals and hit points for ALL features after the new alignment up to the next alignment recall.

[JamesMannes]

Let's say that you have made an alignment, and then measured some features. As you look at the nominals of the features they are not coming out right.

Let's say that the nominals are not coming out right because in the alignment above you used the wrong rotation angle. If you update the alignment to proper rotation value and the question comes up "do you want update the values below?", then at that point, you would answer "yes". The your nominals would update and you would probably see that they are now correct.

Let's say that instead of that scenario, you used the manual origin by accident instead of you DCC measured origin. If you were to go back into the alignment and change it to the DCC origin then you would want to answer "no" because you really didn't change anything just the feature that defined the origin (assuming that both the manual and DCC origin are the same).

[Matthew D. Hoedeman]

WMS. I almost always say NO. Saying YES is good if I have forgotten to put in an alignment and I have programmed features that I want to be in the new alignment. Only works seamlessly when I catch it quickly. Basically, you need to know WHY you are saying YES. PC DMIS will change the nominals and hit points for ALL features after the new alignment up to the next alignment recall.

It is ALMOST worth re-doing the check program if you have to make major changes to the alignment after-the-fact just to ensure that you still ahve cad nominals and not something else.

This is yet another [email protected] good reason for having seperate alignment programs and recall the external alignment. You can change the alignment 57 thousand times and never ahve to worry about it messing up your check program.

[Matthew D. Hoedeman]

Let's say that you have made an alignment, and then measured some features. As you look at the nominals of the features they are not coming out right.

Let's say that the nominals are not coming out right because in the alignment above you used the wrong rotation angle. If you update the alignment to proper rotation value and the question comes up "do you want update the values below?", then at that point, you would answer "yes". The your nominals would update and you would probably see that they are now correct.

Let's say that instead of that scenario, you used the manual origin by accident instead of you DCC measured origin. If you were to go back into the alignment and change it to the DCC origin then you would want to answer "no" because you really didn't change anything just the feature that defined the origin (assuming that both the manual and DCC origin are the same).

IF your nominals are coming from CAD, and you got them from CAD AFTER you did an incorreect alignment, you had better say NO since you got the nominals for the check points FROM the cad. The cad will be correct to the alignment AFTER you fix the alignment and the actuals will then come out right.

[craiger_ny]

Simply put you need to know the answer before you change anything. I do it all the time both yes and no but you need to know before. I don't use cad.

[Matthew D. Hoedeman]

Simply put you need to know the answer before you change anything. I do it all the time both yes and no but you need to know before. I don't use cad.

Don't even need to use cad for it to effect the check points. Pulling XYZ nominals off a print is the same as using cad data, the nominals are set values coming from something other than the actual part sitting on the table.

[craiger_ny]

All I am saying is there is no rule of thumb. To ask "should I check yes or should I check no" is situation dependant and you should know the behavior so you can answer that question before you go editing or deleting alignments.

There is no cookie cutter answer that is all I am saying.

[operator1]

It is ALMOST worth re-doing the check program if you have to make major changes to the alignment after-the-fact just to ensure that you still ahve cad nominals and not something else.

This is yet another [email protected] good reason for having seperate alignment programs and recall the external alignment. You can change the alignment 57 thousand times and never ahve to worry about it messing up your check program.

..guess I'd be better off perfecting my subroutine skills then......
.....it's kinda confusing, but at the same time, it isn't.....I feel like my confidence and insecurities were both offset by 1...update commands to new offset? I don't know!

So basically, I only select "Yes" when I change the alignment for the purpose of changing the features? And I select "No" when...when....when?
You'll have to excuse me...I'm having one of those "days"...

[Matthew D. Hoedeman]

All I am saying is there is no rule of thumb. To ask "should I check yes or should I check no" is situation dependant and you should know the behavior so you can answer that question before you go editing or deleting alignments.

There is no cookie cutter answer that is all I am saying.

OK, how about this ( if I can make it understandable )

You will usually say NO if nominals do NOT come from the actual part you are checking and you will usually say YES if the nominals ARE coming from the actual part you are checking.

Does that come close to a cookie-cutter method?

[Sean Harris]

All I am saying is there is no rule of thumb. To ask "should I check yes or should I check no" is situation dependant and you should know the behavior so you can answer that question before you go editing or deleting alignments.

There is no cookie cutter answer that is all I am saying.

So true. Both yes and no answers have their place. I run into this daily. Sometimes you want the alignment to change sometimes you don't just depends on why you are changing....

[operator1]

IF your nominals are coming from CAD, and you got them from CAD AFTER you did an incorreect alignment, you had better say NO since you got the nominals for the check points FROM the cad. The cad will be correct to the alignment AFTER you fix the alignment and the actuals will then come out right.

And this is where most of my information is coming from now...so if I were to select "Yes" to update commands, then the nominals would change to something off based off the offset/change in the alignment?

[craiger_ny]

I have programs that use anywhere from 6 to over a two dozen alignments. How can there be a cookie cutter answer?

[Matthew D. Hoedeman]

And this is where most of my information is coming from now...so if I were to select "Yes" to update commands, then the nominals would change to something off based off the offset/change in the alignment?

YES, that is wexactly what happens. IF you tell it yes, ALL features after the alignment will change their nominals by the exact same amounts you changed the alignment.