[To...] Posted December 28, 2020 Share Posted December 28, 2020 I am writing a cmm program for a machine using a Renishaw TP20 to measure a turbine with 13 blades. Customer is calling out profile to A B C, on each blade but has specified to take 100 evenly space points at 3 locations on each blade. (1/4 span, 1/2 span and 3/4 span) I've created sections at these 3 locations. Now to my question. Would you create a set of 100 space points from the sections and use space point distances, or would you create a 3d curve of 100 points on each section and set the strategy to take 100 touch-trigger points. With scanning, I would normally triple the number of scanned points but what is normal for touch-trigger points? Or, would you create the curve and use Recall Feature Points to populate the curve data? The benefit of using a curve is the ability to create a profile plot but is using a curve vs space points reliable. Just looking for any feedback......Screenshot 2020-12-28 095022.jpg Link to comment Share on other sites More sharing options...
[He...] Posted December 28, 2020 Share Posted December 28, 2020 Spacepoints will probably give you the most correct results since there is no interpolations or any other black magic happening in the background. The downside is that it will probably take forever to because of the necessary clearance movements. I would try to use use curves and select the option named something like "nominal value" in the strategy. This will measure an actual point at each nominal point. Then I might play around with the calculation method. Left hand side above where you select clearance plane. Finally I would confirm the results by also measuring a few of the points in the curve as space points and see that it gives the same results. (Just during the testing phase and not in the final program.) Link to comment Share on other sites More sharing options...
[To...] Posted December 28, 2020 Author Share Posted December 28, 2020 Please sign in to view this quote. Thank you Henrik. I can keep the excessive moves to a minimum with sub-clearance planes and position points. Link to comment Share on other sites More sharing options...
[Cl...] Posted December 29, 2020 Share Posted December 29, 2020 Hey Tom, couldn't you just use a 2d curve and select Space Point Evaluation from the drop down just below "Comment"? I have not ever applied this option, I saw it and thought, hmmm? Link to comment Share on other sites More sharing options...
[An...] Posted December 29, 2020 Share Posted December 29, 2020 _ Link to comment Share on other sites More sharing options...
[Cl...] Posted December 29, 2020 Share Posted December 29, 2020 Can anyone tell me what this option does? Please sign in to view this quote. Link to comment Share on other sites More sharing options...
[Cl...] Posted December 29, 2020 Share Posted December 29, 2020 I don't ever remember anyone in this forum not giving a "Thank You" for someone's help.Everyone to me seems to be professional and courteous. Link to comment Share on other sites More sharing options...
[To...] Posted December 30, 2020 Author Share Posted December 30, 2020 Please sign in to view this quote. Andreas. I owe you many "Thank You's" for your contributions to this forum. I know you spend a lot of time creating wonderful graphic displays but I must admit, some of them "fly right over my head". I still appreciate them, though. Link to comment Share on other sites More sharing options...
[Cl...] Posted December 30, 2020 Share Posted December 30, 2020 I am glad you admitted that Tom. I thought I was the only one. Some of Andreas contributions make me feel like a Kindergartener attending Yale. Link to comment Share on other sites More sharing options...
[Ri...] Posted January 4, 2021 Share Posted January 4, 2021 I don't see why you need 100 points for such a simplistic shape. I would first test it using say 15 points with a normal curve set to Trigger mode. The 3-1 rule is a suggestion, not a law. If you have a 30k nominal point Curve, you aren't going to blow up the computer/controller trying to process 90k points. Lol. Link to comment Share on other sites More sharing options...
[Ow...] Posted January 4, 2021 Share Posted January 4, 2021 Sounds like a great opportunity to show a customer how much better data they could obtain to improve their processes and time $ saved by upgrading their CMM by 30 years....you might even get some free Zeiss apparel from the sales rep 🤣 . just saying. Haven't used it myself but, blade-pro would seem to be the best option? Link to comment Share on other sites More sharing options...
[SH...] Posted January 4, 2021 Share Posted January 4, 2021 Please sign in to view this quote. This is a simple shape for you?. Link to comment Share on other sites More sharing options...
[Ri...] Posted January 4, 2021 Share Posted January 4, 2021 Turbine blades are not that complex, no. Measuring a turbine blade is a different story, depends on the sensors/accessories available. Link to comment Share on other sites More sharing options...
[Cl...] Posted January 4, 2021 Share Posted January 4, 2021 Please sign in to view this quote. Years ago I worked in aerospace. We made the F-22 vectoring exhaust panels. Similar to a turbine blade in some respects. The CMM program (Virtual DMIS / PH10) took hundreds of profile points, took hours.F-22A%20-%20engine%20nozzles.jpg Link to comment Share on other sites More sharing options...
[Ri...] Posted January 4, 2021 Share Posted January 4, 2021 Yeah. If you have to take single points it's a long day for you. Inspected a tool for an aerospace company that they said took them 3 days to inspect because of the point requirements. It took us an hour to inspect, and about 2 hours to perform the free-form calculations. Link to comment Share on other sites More sharing options...
[SH...] Posted January 4, 2021 Share Posted January 4, 2021 Yes, it is clear his customer don't have curve . Link to comment Share on other sites More sharing options...
[To...] Posted January 4, 2021 Author Share Posted January 4, 2021 Please sign in to view this quote. When the customer is a university doing protoype development for the military......Screenshot 2021-01-04 153651.jpg Link to comment Share on other sites More sharing options...
[Ri...] Posted January 4, 2021 Share Posted January 4, 2021 Then I would just do 100 trigger points. Grab some popcorn. Link to comment Share on other sites More sharing options...
[To...] Posted January 4, 2021 Author Share Posted January 4, 2021 Please sign in to view this quote. My customer has curves but is using a Renishaw TP-20 so I wasn't sure if curves was a good option for a touch-trigger sensor. Link to comment Share on other sites More sharing options...
[To...] Posted January 4, 2021 Author Share Posted January 4, 2021 Please sign in to view this quote. I let the customer decide how he wanted to measure the parts. Since the drawing called for Profile and plots are readily available, he decided to do the curves option. Link to comment Share on other sites More sharing options...
[Ri...] Posted January 4, 2021 Share Posted January 4, 2021 Please sign in to view this quote. Yeah. That was my suggestion either way. I was just saying that the 100 trigger points was fine. I wouldn't worry about the 3-1 rule unless you are explicitly seeing issues (especially if you are doing transitions). Link to comment Share on other sites More sharing options...
[To...] Posted January 4, 2021 Author Share Posted January 4, 2021 Please sign in to view this quote. I used the Curve-dependent option and selected Nominal Values in the strategy.Screenshot 2021-01-04 160556.jpg Link to comment Share on other sites More sharing options...
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