[To...] Posted June 17 Share Posted June 17 I have my thoughts on what is going on with this circle, but I'd like to hear what you all think. Link to comment Share on other sites More sharing options...
[Ch...] Posted June 17 Share Posted June 17 i've seen this once or twice before, I think I recall it was a hole and something was causing probe to shank, or it was really out of round ,etc. 3 Link to comment Share on other sites More sharing options...
[Ja...] Posted June 17 Share Posted June 17 I suspect similar to Chris - probe shanking out, an out of round hole or a burr, or a combination of all three. 1 Link to comment Share on other sites More sharing options...
[Ke...] Posted June 17 Share Posted June 17 (edited) I see this a lot, when I am measuring a small internal diameter with a "not small enough" stylus. e.g.: inspecting a 4mm dia hole with a 3mm stylus. After I use a 2mm or 1.5mm stylus, the geometery looks good; but the values are no different than the larger stylus Edited June 17 2 Link to comment Share on other sites More sharing options...
[To...] Posted June 17 Author Share Posted June 17 The thing that puzzles me is the low form value. Link to comment Share on other sites More sharing options...
[Du...] Posted June 17 Share Posted June 17 Do you have Magnification for the feature on? Link to comment Share on other sites More sharing options...
[Ch...] Posted June 17 Share Posted June 17 Please sign in to view this username. I'm with you, what's up with the good form value? Looks heavily filtered. I'd look at the unfiltered data and check difference been min circumscribed and max inscribed. 1 Link to comment Share on other sites More sharing options...
[To...] Posted June 17 Author Share Posted June 17 (edited) No mag. No filters or outliers. Not sure why scanning 750 degrees. LSQ. Haven’t checked mask settings. Edited June 17 Link to comment Share on other sites More sharing options...
[Ch...] Posted June 17 Share Posted June 17 Please sign in to view this username. something is masking out points. its set to 1048 points but only 462 are used for the evaluation. 1 Link to comment Share on other sites More sharing options...
[Ke...] Posted June 17 Share Posted June 17 Try taking discrete points... maybe a dozen or so? Link to comment Share on other sites More sharing options...
[Pe...] Posted June 17 Share Posted June 17 I've seen calypso make some pretty funny shapes when a hole is so far from where it should be. Looking at your X and Z. 1 Link to comment Share on other sites More sharing options...
[Mi...] Posted June 17 Share Posted June 17 (edited) Is there a loose/damaged component? The low form error is confusing, though. Does it have something to do with the fact that it's labeled a cylinder but has the circle symbol in the feature window? Seems like there was some tinkering with that feature at some point. I agree with the previous replies about shanking and burrs but I'd think the form error would be higher, even with filtering. I've seen something similar to that caused by a cracked (off brand) carbon fiber extension. The crack was causing the extension to flex more one way than the other and the result was similar to what you have pictured. Edited June 17 More information Link to comment Share on other sites More sharing options...
[Tr...] Posted June 17 Share Posted June 17 Had this happen when the hole is small, relative to probe, and out of expected position. Link to comment Share on other sites More sharing options...
[To...] Posted Thursday at 11:53 AM Author Share Posted Thursday at 11:53 AM Please sign in to view this quote. Please sign in to view this username. I remember many years ago that masking was tied solely to the first .25 seconds of the beginning of a scan, and it still is when scanning less than 360°. So, when you scanned 380° on a circle, the masked points might only be a portion of the 20° over-scan relative to the scanning speed. Then, Calypso changed to masking whatever the over-scan amount was. My assumption is that even though they are scanning 750°, the resulting circle is only using the data from the last 360° of the scan. Link to comment Share on other sites More sharing options...
[To...] Posted Thursday at 12:08 PM Author Share Posted Thursday at 12:08 PM (edited) For a little more detail, the basic shape is a cube with many same-sized holes machined parallel to axes created from opposite corners of the cube. All of these holes exhibit the same odd shaped data set. With the exception of the good form, I believe the stylus is shanking. These results lead me to believe there is either an issue during the machining or the base alignment. The measurement plan is from the customer and the results from a part they machined on their machine. I just need to be sure before I tell the customer. Edited Thursday at 12:13 PM 1 Link to comment Share on other sites More sharing options...
[Ri...] Posted Thursday at 06:30 PM Share Posted Thursday at 06:30 PM Are you using an L shaped probe? Link to comment Share on other sites More sharing options...
[To...] Posted 4 hours ago Author Share Posted 4 hours ago Please sign in to view this quote. no Link to comment Share on other sites More sharing options...
[To...] Posted 4 hours ago Author Share Posted 4 hours ago It has been determined the part is being machined off axis and when it is mounted on cmm, the probe is shanking. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in