Change approach distance in Y-

[[St...]]

I want to shorten the approach distance for a probe measuring a feature on the bottom of a part when it moves from the y- direction. Currently, the stylus stops about 2 inches from the part before driving in, but I want to reduce this distance. Adjusting the clearance and retract distances only changes the distance right before the measurement, which isn't solving the issue. Can someone help with this?

[[Ri...]]

This distance is set by the size of your clearance cube.

Measurement Tab - Clearance Plane - Adjust the appropriate axis.

[[St...]]

Thats what i thought too. Here is my current clearance settings and a picture of the current distance. Ideally I would like to approach from Z+ close to the part and then come in a probe it. But it just tries to drive straight through the part.

IMG_1577.JPGCapture.PNG

[[To...]]

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When approaching from a direction other than Z, the clearance cube's job is to protect you from hitting the part with the stylus when the stylus comes down in the -Z direction. However, it is also designed to protect the entire Z ram. In other words, if the stylus extends out further than the ram, the amount of clearance will protect the stylus. If the stylus does not extend out beyond ram, the amount of clearance will protect the ram. On an RDS, like your situation. the stylus is way in front of the ram, so the clearance is designed to protect the ram.

You could use CP+Z and make sure the clearance distance of the feature is adequate to protect your probe from hitting the part as it comes down.

[[St...]]

Yeah i tried using Z+ and putting like 20 in the clearance and retract but it tries to drive through the part to get to the feature

[[Da...]]

Double check that you have the correct probe called out for the operation, accidently switching can cause problems.

[[To...]]

If you follow Dave's post and it's ok, then check the Y values of your 2 and 4 styli. Make sure the +Y styli is larger than your +Y styli. I've seen cases where people qualified the 2 with the 4 stylus and the 4 with the 2 stylus.

[[Da...]]

Reduce the sensor diameter in the probe tab to 1.5 (CMM configuration)

[[Ro...]]

As David mentioned, you need to reduce the sensor diameter.

Sensor Diameter.jpg

[[St...]]

This worked well to fine tune the navigation thank you!

[[To...]]

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I know you have come up with a work-around to your problem. Hopefully, you'll never have a situation where this change will cause a problem.

If you don't mind, I'd like to dig into why the CP+Z didn't work. What type of feature are you measuring? What is the Space Axis direction. I'll assume it is a circle with a +Y space axis. Did you create the feature from a model or did you use "teach" mode? Maybe a screen capture of the feature window would be easier

Here's a tip you might find useful. Go into CAD > Settings > Strategy and tick Clearance Positions. Then, open the circle. You should now see arrows that indicate the clearance and retract positions. The end of the line without the arrow indicates the center position of the probe sphere at the clearance distance and the tip of the arrow indicates the sphere center at the retract distance.
This might help you understand what is going on. Note: if clearance distance is 0.0, the arrows will not appear.

[[Mi...]]

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I just played with this setting because it's very cool and I never had...

The clearance distance can't be 0, but it also has to be more than the retract distance for it to show arrows, at least in 6.6.28

[[To...]]

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Good to know. Generally, this is my "go to" tool when I need to increase clearance distance to clear an obstacle without using a position point.