PC DMIS If commands

[pcdmisstudent]

Hello all!
We have a part that consists of a big cylinder (Ø35mm). 45mm inside the cylinder theres two small Ø6 holes. I wish to measure the distance between these holes.
The problem is that the probe is very very close to the cylinder when measuring it (about 1mm clearance between probe and cylinder).

So if the Ø35 cylinder is smaller than nominal, the probe will crash into the cylinder when measuring the Ø6 holes. (I even measure them as half-circles towards the center of cylinder).
So to avoid this crashing when operators are using the machine I wish to put in a If/else command that says IF the Ø35 cylinder is smaller than 35, dont measure the Ø6holes. Else, measure them.

Anyone has any idea how to solve this? I havent even tried making any if/else commands yet because my knowledge of it is very poor

[JEFMAN]

You could try :
Input a label after measuring Ø6 holes (LAB1). Then :
IF CYL1.D<35.0
GOTO LAB1
END IF.

Check that all clear plane, rotation head (...) are ok in this case !!!!!

[pcdmisstudent]

Merci Jeff!
That worked

[pcdmisstudent]

Hey another question
Now if the cyl 35 is smaller than 35. can i report the measured value in a comment?
Like: assign/v1=cyl.D

then in the operator comment "35h7 is too small, measured diameter is "v1"?

[JEFMAN]

Operator comment, or report comment ?
In both cases, just add the line in the comment :
"35h7 is too small, measured diameter is :" +CYL1.D +" mm"

[pcdmisstudent]

Ah i thought you had to assign it to some variable. Ill try that out later. Thanks a lot!

[pcdmisstudent]

Hey, i just noticed a problem.
I put the label at the end of the program, so even if the cylinder is above Ø35 and it measures the small holes etc. It will still run the label at the end of the program.
I only want it to run the label if the cylinder is too small.
Any ideas how i can solve this?

[JEFMAN]

Maybe just the place of the label ?
The prog should be (as I understand !) :
ALignment
Measurement of Cylinder Ø 35
If statement / goto
measurement of Ø6 holes
Label
others features
end of program.

[pcdmisstudent]

Ah my idea was just to end the measurment program compeltely if the Ø35 was too small.

[VinniUSMC]

Hello all!
We have a part that consists of a big cylinder (Ø35mm). 45mm inside the cylinder theres two small Ø6 holes. I wish to measure the distance between these holes.
The problem is that the probe is very very close to the cylinder when measuring it (about 1mm clearance between probe and cylinder).

So if the Ø35 cylinder is smaller than nominal, the probe will crash into the cylinder when measuring the Ø6 holes. (I even measure them as half-circles towards the center of cylinder).
So to avoid this crashing when operators are using the machine I wish to put in a If/else command that says IF the Ø35 cylinder is smaller than 35, dont measure the Ø6holes. Else, measure them.

Anyone has any idea how to solve this? I havent even tried making any if/else commands yet because my knowledge of it is very poor

You're using a star probe? How much clearance do you have between the probes and the cylinder wall?

Have you tried using smaller prehit/retract values, smaller avoidance moves (if you're using that), or changing the orientation of hits in the circles?

[VinniUSMC]

Oh, I understand now. I was picturing perpendicular holes that went through the cylinder. That makes sense.

Sorry, not 45 to -45. 45 to 45. That's a full 360 circle. If the start and end point are the same, the circle is 360. If that is still a bit too much, open up the start and end point by 5 degrees each. Maybe 0-180 is the best you can get I don't know. I was just trying to make a suggestion that was something other than not measuring the features.

Just a Xmm ball. I was thinking it was a star probe to measure perp holes, so I had the whole picture in my mind completely wrong. What size ruby are you using? Can you increase the size? Can you increase the length?

[pcdmisstudent]

@VinniUSMC

No worries , Im just thankful for replies

The ruby tip im using right now is Ø4. The next biggest one is Ø6. (and the hole is Ø6 with a plus tolerance of +0.1 and +0.2). So technically i could use the bigger tip and only have 0.1-0.2 mm clearance (assuming the part is within tolerance).

I problably have an carbon fiber extension around i could put on, but im scared that it will mess with the other programs we ve made with this tip.

[VinniUSMC]

Well, lol, yeah, a 6mm ball in a 6mm hole isn't really a good idea.

What about using a small angle rotation? Like 5 or 7.5 degrees on the A knuckle? Would that be workable?