Loading a Stylus System mid program inside the part

[[Jo...]]

I will be working on a program on a pretty big part, 600mm long. The part is a rolled shell with side ledges that I need to measure roughly 400mm inside.

The problem is our CMM is not long enough to clear the part within the CMM limits on the long probe I developed.

Here is my plan to overcome this...

1. Start the program using a shorter probe for alignments.

2. Return the probe to the rack.

3. Move the machine head to the front of the part at the "load/unload location."

4. Manually load the new long probe.

5. Measure all internal features with the new long probe.

6. Return to the probe "load/unload location."

7. Manually unload the long probe.

8. Perform an automatic probe change and continue measuring the rest of the program.

 

How should I approach this? I do have PCM. I need advice for #3, 4 & 7.

Appreciate the help!

[[Do...]]

Probably not the most elegant solution, but you could terminate the program once it reaches those load/unload locations. Swap probes manually. Then continue the program, unchecking the "clear existing results" box from the run menu. 

[[Du...]]

Im not sure if you can have it move without a probe in the head, haven't tried it, you could probably have a dummy probe(only adapter plate) and have it move to where you need it and do a manual swap at that point

[[Ra...]]

Personally, I just wouldn't do step 2. Just have a move to the front of the machine on the last feature the first stylus measures. When the next feature requires the long stylus not in the rack, it will prompt you to manually change styli. Then when the long stylus is done, make a move to the front of the CMM on the last feature, and just have the next feature require the first stylus. Do another manual stylus change, and you're done.

The only difference is you're first stylus isn't in the rack while the long stylus is active. A tabletop stylus holder is pretty easy to make.

I've never had success doing anything without an active stylus in CNC mode.

[[Cl...]]

If you don't assign a location on your probe rack for new probe you will get a prompt to manually load it when it is time to check the first feature using that probe and another to unloaded it after the last if there are more features to be checked with a different probe.  You can manually move the head and load the probe wherever you need to but you might also need to make a sub-clearance plane if you have multiple features inside the part that will need the long probe so that it doesn't trying to full retract outside of the clearance plane of your part.  If there is a machined face inside the part you can as a zero point (X, Y, or Z depending which axis you are traveling) I would have that been the first feature you check and make it a manual check instead of a CNC then you have can use that face to set your sub-clearance plane.

[[Ke...]]

Depending on what version of Calypso you have, this function may exist natively for you 

 

[[Ch...]]

This feature is available for use in CALYPSO 2025 (8.0) and referenced in the Operating Instructions which I have attached - Editing the travel paths section (6-97). 

It is called Path for "threading" without stylus system section 6-115 

If you want to measure one or several features in a hollow space (cavity) whose entry is too small for the direct travel path of the stylus system, the stylus system must be removed and mounted again by hand inside the cavity.
For this to run smoothly in the CNC run, you must create a path for threading without a stylus system with stops for removing and reattaching the stylus system. For this, use the path feature “Threading” During the CNC run, CALYPSO stops in front of the cavity. You can give the command in CALYPSO as well as on the control console to release the stylus system and prevent the stylus system in the CMM from falling down. CALYPSO continues the measurement run and positions the probe in the cavity. A message is displayed that the stylus system can be reattached. After the attachment, CALYPSO continues and the path is executed to the end.
The features in the clearance group inside the cavity are measured and the path is executed backwards.

Calypso_basic_cnc.pdf

[[Jo...]]

Thanks all for the feedback everyone. All great ideas. 

The down-and-dirty method might get me by in a pinch, but I eventually want it to be more optimized. That's where I may try the ladder suggestion. 

 

Thanks again!