Need help with flowline toolpath

[Bob W.]

I have a part that I am trying to squeeze every second out of and one of the features would be most efficiently machined with a flowline toolpath but I can't get it to work.  Imagine plunging a 1" ball mill .25" into material and machining a 90 degree arc (2D contour) , then retracting, and this is what the feature looks like.  The part is a consumer product so it needs to look PERFECT which is why I don't do just that.  I worry about possible dwell marks at the entry and exit and the part isn't very well supported to take the pressure of that cut.

 

I need flowline because with the spiral motion the tool never slows down during transitions from pass to pass.  I have tried projecting a pocket toolpath but the transitions aren't smooth.  I have tried reconstructing all surfaces from scratch but flowline still doesn't like it.  I have tried blend but couldn't get it to work right.  Any ideas on how to accomplish this?  I am looking for a toolpath that follows the external shape of the feature and spirals inward with smooth transitions so the cut load will be consistent and the machine will haul @ss.  The first cycle was 1 hr 58 min and our last was 36 min.  My goal is to get it under 30 min.

[duckdogers]

I use flowline all the time but I,m not quite sure what you are asking anyway of sharing file or something similar

[So not a Guru]

Have you tried 5-axis flowline with the tool axis restricted

[Müřlıń®]

I have a part that I am trying to squeeze every second out of and one of the features would be most efficiently machined with a flowline toolpath but I can't get it to work.  Imagine plunging a 1" ball mill .25" into material and machining a 90 degree arc (2D contour) , then retracting, and this is what the feature looks like.  The part is a consumer product so it needs to look PERFECT which is why I don't do just that.  I worry about possible dwell marks at the entry and exit and the part isn't very well supported to take the pressure of that cut.

 

I need flowline because with the spiral motion the tool never slows down during transitions from pass to pass.  I have tried projecting a pocket toolpath but the transitions aren't smooth.  I have tried reconstructing all surfaces from scratch but flowline still doesn't like it.  I have tried blend but couldn't get it to work right.  Any ideas on how to accomplish this?  I am looking for a toolpath that follows the external shape of the feature and spirals inward with smooth transitions so the cut load will be consistent and the machine will haul @ss.  The first cycle was 1 hr 58 min and our last was 36 min.  My goal is to get it under 30 min.

 

Rebuild the surfaces with Coons so that it is one surface instead of many and flowline should work better

[crazy^millman]

Morph Between 2 Curves set to Spiral not give you what you want? Net Surface should build a nice surface is you want to go to one surface.

[?Mark]

Create your own surface with revolve. That will create the cleanest flow-line toolpath

[Bob W.]

I have created perfect surfaces using the revolve surface feature (3X).  The flowline curves look perfect and Mastercam will create perfect flowline curves.  In the flowline toolpath the cut direction looks perfect as well.  For some reason it just doesn't like the geometry.  How do I merge surfaces?

[Bob W.]

Morph Between 2 Curves set to Spiral not give you what you want? Net Surface should build a nice surface is you want to go to one surface.

Winner winner chicken dinner!  Thanks Ron.  After tweaking I got a perfect toolpath out of this.

[crazy^millman]

Winner winner chicken dinner!  Thanks Ron.  After tweaking I got a perfect toolpath out of this.

 

No problem Bob glad I could help point you in the right direction.

[crazy^millman]

Another old school trick for those playing along at home. You can draw a toolpath and then use that to drive a toolpath. In essence that is all any toolpath is really doing in the back ground is taking a method and then mapping that method to a surface to be machined. You have a method you want to try then draw the method and then use 3 Contour to follow the method. No it will not cut the shape perfect. That is not what you are after. What you are after is motion you can then project onto the surface you want to cut. Once you have it all like you want then you can give it a shot. Best way to make sure you get exact motion is more work, but possible. Offset the surfaces you want to cut the Radius of your tool. That will then be exactly where the tool will be traveling. Then use that to work from and you will have almost the exact toolpaths you have drawn on the part to machine. Tons of work why we have a CAM system, but before I had CAM that was how I mapped all my NC code. Once you see the patterns in shapes then you can get trick and see what common things certain shapes share and you dial into a process that really allows you dial toolpaths down to the exact place you want the tool to be.

 

Old school, but I have a part right now that I was hoping Opti-Rough could handle in one operation. I am breaking it up into 30 ops and more than 30 stock models to get the exact motion I want. Like Bob it may only reduce the run time by 10% going about this this over what Opti-Rough threw at it, but I want exact motion in certain way in certain spots. To acheive that I will spend the extra 20 hours programming the part to make sure I give the customer the very best program I think possible. 10% may not seem like a lot, but one 4 parts a week running 12 hours each my 20 hours of extra time programming the part is saving the customer 1.2 hour per part times 4 parts a week times 50 weeks in a year they are running them. That is a total saving if it goes the way I think of 300 hours. I say it is 20 hours well spent.

[Bob W.]

I look at it as giving myself a raise.  This $80 part at 118 minutes gave a shop rate of $40/hr.  At 36 minutes it is $133/hr.  At 30 minutes we will be at $160/hr.  Pretty good gain for 3-4 hours of effort.

[crazy^millman]

I look at it as giving myself a raise.  This $80 part at 118 minutes gave a shop rate of $40/hr.  At 36 minutes it is $133/hr.  At 30 minutes we will be at $160/hr.  Pretty good gain for 3-4 hours of effort.

 

Bob yes sir and why your business is doing well. You see the meat and potatoes of the effort Crazy how many just don't get it.