Part too long

[[Ni...]]

Hi all,

I have a straightforward piece that's too long for my CMM, I need to check positioning on holes. I am aware there is a method to check the whole piece in two parts. Can someone help me out?

[[De...]]

As long as you can have enough travel to access your datum features from either side, you can write two programs, or 1 program with 2 miniplans. If you can't get to the datums from either end then you need to have a discussion with your engineers to see if other features could be used as datums, or if you can simulate the datums in some manner. Its really difficult to answer this question with seeing what you are talking about.

[[Cl...]]

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Is there any way to use a physical datum simulator. Something that makes contact
with the datum in such a way that it can be extended to inside the measuring range.
For example, if you need to probe a plane datum, but it's outside the range of the probe.
You could use grade 0 gage blocks, place one end against the plane, measure the opposite
end then translate back the blocks length.

[[Ke...]]

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Check this post.
There is a "How to leapfrog" PDF that is posted in the comments

[[Mi...]]

Depending on how much too long, and if this is an XT machine you might be able to simply built a probe system that can reach outside of the machine volume.

The Leepfrog option is cool... but it requires manual points, and for you to run from Characteristic list.

[[Da...]]

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No, it works with automatic points, too. Using it every day, mainly to measure parts from both sides. Basically it's making a coordinate system with elements that can be reached from both sides or in both setups, measuring what you need, moving or turning your part, measure the same (or similar) elements, equate the alignment, and measuring the rest of the part.

You can use all elements to evaluate, except the "in-between" ones after moving the part and before the equate alignment. The only thing you need in an automatic program is an external start alignment for the second setup or an alignment that can be derived from the first setup (which you can use as a sort of start alignment to basically locate the part).

[[Ro...]]

In my CMM, for parts longer than 52 inches in length, but less than 66 inches, i can remove my tool changer.
I have been able to just set the part at an angle a couple times to sneak a couple extra inches, but that only works for skinny parts like a long bar or something like that.

[[Ch...]]

CALYPSO's Base Alignment Match tool is designed for measuring long parts that need to be shifted mid run two account for the additional sections of the long part. They can be a bit tricky to setup but the CALYPSO Expert class goes into great detail on this topic.

There is a also a ZEISS Knowledge Base Article that goes into detail as well: https://portal.zeiss.com/knowledge-base?id=522718