2d Dynamic mill path direction

[MrFish]

Does anyone have any tricks to control which way the cut flows from , i.e. left  to right, right to left

 

I have a part that is symmetrical and has an open end transitioning to a slot. When cutting from the front I get flow from the open end to the slot end which produces good swarf management , but when I cut the same geo from the back I get flow from the slot end to the open end and this leaves a nasty island that wants to get sucked into the cutter and break it !

 

[David Colin]

In toolpath parameters you can can control start of cut (left, upper left,...) that should do what you re looking for. I don't really like that but you can try mirror tranform too.

[Colin Gilchrist]

Which version of Mastercam? With the release of X8 or X9, they added some great new options for the 2D High Speed Dynamic Tool Paths.

 

The option I'm thinking of is "Air Chaining". You basically select a single closed chain as the "area" you want to machine out. Set the option to "outside" in the chaining selection dialog for the toolpath, and then use the "air chain" to select a "partial" chain. This tells the algorithm that the "air chain" is an "open area".

 

By having the path set to "outside" approach, and telling the operation "where the open end is", the toolpath should always start on the "air" side, and work its way into the pocket. I've had great results just by using those options, and sometimes modifying the wireframe geometry to keep the tool from "wrapping" around an edge where I don't want it to go...

 

 

Say for example, you have a chain that looks like the following. You want to pocket out the material, but only the "red" area is the "Air" chain area. If you just chain it "as is", sometimes it will "wrap" up past the "non Air" edges while machining its way in.

               _________

               |                |

               |                |

               |                |

               |                |

               |________|

 

 

Now, if you modify the chains a little bit, to extend the "walls" past the "air chain", it will only enter where the red partial chain is. Obviously this is very crude ASCII art, but I'm just using it to demonstrate the thought process here...

 

        ____________

        |___                 |

               |                |

               |                |

          __|                 |

         |___________|

[lowcountrycamo]

Which version of Mastercam? With the release of X8 or X9, they added some great new options for the 2D High Speed Dynamic Tool Paths.

 

The option I'm thinking of is "Air Chaining". You basically select a single closed chain as the "area" you want to machine out. Set the option to "outside" in the chaining selection dialog for the toolpath, and then use the "air chain" to select a "partial" chain. This tells the algorithm that the "air chain" is an "open area".

 

By having the path set to "outside" approach, and telling the operation "where the open end is", the toolpath should always start on the "air" side, and work its way into the pocket. I've had great results just by using those options, and sometimes modifying the wireframe geometry to keep the tool from "wrapping" around an edge where I don't want it to go...

 

 

Say for example, you have a chain that looks like the following. You want to pocket out the material, but only the "red" area is the "Air" chain area. If you just chain it "as is", sometimes it will "wrap" up past the "non Air" edges while machining its way in.

               _________

               |                |

               |                |

               |                |

               |                |

               |________|

 

 

Now, if you modify the chains a little bit, to extend the "walls" past the "air chain", it will only enter where the red partial chain is. Obviously this is very crude ASCII art, but I'm just using it to demonstrate the thought process here...

 

        ____________

        |___                 |

               |                |

               |                |

          __|                 |

         |___________|

Crude maybe, but very smart Colin.

[SlaveCam]

Air chaining is the best thing since sliced bread. Could not live without it any longer.

[MrFish]

Which version of Mastercam? With the release of X8 or X9, they added some great new options for the 2D High Speed Dynamic Tool Paths.

 

The option I'm thinking of is "Air Chaining". You basically select a single closed chain as the "area" you want to machine out. Set the option to "outside" in the chaining selection dialog for the toolpath, and then use the "air chain" to select a "partial" chain. This tells the algorithm that the "air chain" is an "open area".

 

By having the path set to "outside" approach, and telling the operation "where the open end is", the toolpath should always start on the "air" side, and work its way into the pocket. I've had great results just by using those options, and sometimes modifying the wireframe geometry to keep the tool from "wrapping" around an edge where I don't want it to go...

 

 

Say for example, you have a chain that looks like the following. You want to pocket out the material, but only the "red" area is the "Air" chain area. If you just chain it "as is", sometimes it will "wrap" up past the "non Air" edges while machining its way in.

               _________

               |                |

               |                |

               |                |

               |                |

               |________|

 

 

Now, if you modify the chains a little bit, to extend the "walls" past the "air chain", it will only enter where the red partial chain is. Obviously this is very crude ASCII art, but I'm just using it to demonstrate the thought process here...

 

        ____________

        |___                 |

               |                |

               |                |

          __|                 |

         |___________|

Hi Colin

 

Thanks for waking me up. I new about air chain but had not thought to try it. This worked a treat and actually produced a better toolpath than I had on the good side ;-)

 

This forum is one reason Mastercam is so powerful !

[MrFish]

In toolpath parameters you can can control start of cut (left, upper left,...) that should do what you re looking for. I don't really like that but you can try mirror tranform too.

For your interest David, I had tried these controls and they did nothing at all to change the cut flow. I have seen this before and I think unless the chaining used is very simple the processing seems to just ignore this or maybe override it .

[jlw™]

I use this all the time, can you upload a file?

[MrFish]

I use this all the time, can you upload a file?

sorry no more than the stock picture in original post.

[Colin Gilchrist]

In toolpath parameters you can can control start of cut (left, upper left,...) that should do what you re looking for. I don't really like that but you can try mirror tranform too.

 

This option really only works well when you are completely machining away the entire chain of stock. So if you chain a single rectangle for example, and use the "outside" cutting method, then it will let you choose the start point as one of the corners or mid-points of the block. (Yes, it does also work on more complicated chains as well.) The issues come into play when you are using Avoidance Chains. When you start to mix them, then the start-point options "work" for positioning the tool, but it won't affect the "cutting motion" the same way as just a single "stock" chain will.

[Mick]

Timing is everything. Hah, I was just experimenting with some toolpaths, and I had a prime example of where this was needed. I actually tried the Air Region earlier and got what I was trying to achieve, and then came across this thread

[Teh Bear without Brains kinda idiot]

 nasty island that wants to get sucked into the cutter and break it

````````````````````

cHANGE YOUR CUTTING DIRESTION FROM CLIMB TO CONVENTIONAL and the island

will be pushed out of the mill (much better scenario)

Happened to me lot of times

HTH