Showing results for 
Search instead for 
Did you mean: 

Learn how to machine turbomachinery components with NX CAM

Community Manager Community Manager
Community Manager


NX has specialized functions for milling impllers and blisks. This tech tip introduces these specialized functions and shows how to use them in various situations.


(view in My Videos)


Created with NX 8.5



NX CAM provides several specialized operations and options to machine turbomachinery parts, including parts with primary and secondary blade profiles:

  • Roughing
  • Blade finishing
  • Hub finishing
  • Blend finishing

Do you have a question?

Click 'Add a Comment' below to ask it. (You must be signed in to access this feature.)




About the Presenter


Holder.jpg Eddy Finaro started his professional career as a mechanical engineer working with various airborne mechanical systems. He spent 8 years as an Application Engineer and Product Manager with Cimatron. Since joining Siemens PLM 5 years ago he has worked as an NX CAM Product Manager responsible for complex milling. His expertise is in 3- and 5-axis milling, particularly complex parts such as impellers, blisks, and airframe parts, etc. Eddy holds a M.Sc. degree in Aerospace Engineering. On his free time Eddy enjoys Mountain Biking, Hiking and mentoring a First Robotic Competition Team.


Derek Hart
... if we're not having fun, we're not doing it right!

Good Afternoon Mr. Finaro, the past week I programmed and milled my first turbo impeller using the turbomachinery package.


Tha impeller that I made has 18 identical blades (no splitters) and it's a common radial impeller made in aluminium.

The geometry of the blades should be not very complex and I tryed to finish them in one pass using the "swarf" finishing like you show in the video. Unfortunately I can't obtain the correct toolpath, the tool doesn't stay in contact with the part all the time.


I am using a conical ball end mill, diameter 4mm, conical shape of 3° and with the cutting lenght a bit more than the maximum height of the blade (42mm the mill, 40mm the blade), but I tried to define an ipotetical cilindrical mill with ball end, diameter 6 and lenght of 75mm to see if the geometry of the tool was the problem. The blend radius on the bottom of the blade is 2.5mm.


I tried to mill it in 1 single pass and in 4 or 5 passes, and every level is not worked all the time with the flank of the tool. It starts right but when the interpolation became more complex the tool choose a different way. I finished it correctly with the automatic axis configuration but the cycle time is very longer.Blade_Swarf_Finishing.jpg.


I tried to swith off the collision check, and modify some parameter on the minimum movement of the axes but without success.


The same impeller was produced by an other company and the blades seems to be finished in swarf method.


Any suggest?


Thank you in advance


Maurizio Osler

Perfection Lab s.r.l.

Community Manager Community Manager
Community Manager

Hi Mr. Osler,


There may be an ENV (environment variable) to set. Can you tell us what software version you are using?


Good morning DerekHart,


I am using NX MP1


Waiting for your kind reply, best regards.

Community Manager Community Manager
Community Manager



This ENV can be applied starting 8.5.2.


Starting in NX9.0.1, there is a UI "collision check" checkbox for it on the "Swarf Blade" dialog, so the ENV is no longer required.


Hope this helps. If you continue to have trouble with it, we should probably look at the part file.


Thank you very much DerekHart, I setted the ENV and now the blade is perfectly finished in 1 pass.


I hope to try the result on the real part in the next 2 weeks, I hope to obtain a good surface finishing.


Thank you again!

LIVE Tech Tip Webinars
Watch NX experts demonstrate manufacturing best practices. Stay online for Q&A.