Impeller Cast/Machine Merge Failure

[SolarMike]

Hello everyone.


I'm having problems with a cast impeller using Wildfire 1. The casting has a family table of about 13 different impellers with different sizes(inducer/exducer increase in size, but radially the same). There's a "semi-finish" part that leaves stock added in certain tight tolerance areas (labyrinth seals, press fits, etc). Finally there is a final machined part that grinds off that stock added. Each part has a .0006 absolute accuracy. Yet, the final machining part hangs up on 5 of the 13 instances becausethe external merge failed. The merge is the first feature of the final machining and it fails... I checked these instances in the semi-finish model and they successfully verify. How can the merge fail?? It doesn't make any sense any nobodyhere can see why it fails. Pleasehelp.


Thanks.
Edited by: SolarMike

 

[wetricb]

Just a thought. Instead of adding material and merging the features (if I understand correctly), try making the raw casting a part and then make an assembly assemble the raw casting to it and then add assembly cuts/features to show the machining operations. Hope this helps.


Wheatchex

 

[SolarMike]

There's no material added... it's just extra material left from the casting so we can grind down the critical areas in house. There are only cuts in the semi-finish and final machining parts. Regardless, I figured out why it wasn't working. After hours of messing with small, insignificant parameters and options I realized I was on an older release. I upgraded WF to release M240 and that was it... ridiculous!!


Thanks wetricb for the reply...

 

[dougr]

NB For merges to work successfully the absolute accuracies in each must match.


Presumably you have 2 merges for each finished part ??? (cast-semi/machined and semi-machined/finished ?)


Look for the part/instance with the smallest absolute accuracy (ie smallest edge) and use this for all generics (and subsequentlyinstances).
Edited by: dougr