2D Pocket Helix/Ramp Entry Point Feature Request

[JamesCNC]

Can the developers of MasterCAM please add a feature to the 2D Pocket operation allow you to make the Helix or Ramp entry point to be tangent to the starting point of the pocket roughing toolpath? I understand you can define a point and use that as the starting point but this is difficult if the starting point of the roughing operation isn't directly in the center of the part. This feature is available in other operations like Area Mill and Dynamic Mill but not 2D Pocket. I believe this simple feature would make the 2D Pocket operation much more user friendly and useful. Please see attached image for reference.

 

[Colin Gilchrist]

James,

Use the XY Clearance function to move that helix position closer to the center of the pocket. Use the "preview toolpath" button on the top row of the dialog box, to see the change. This allows you to iterate quickly through the changes to find the correct XY Clearance value.

But really, 2D Pocket is a very old path, and there are better options.

Use 2D Dynamic instead. It is a much, much better toolpath. Dynamic uses Controlled Radial Engagement, to keep your tool load constant.

Set the option to "inside" and it is a "pocket". Set it to "outside", and it will approach from the outside and machine inwards.

I cringe when I see programmers these days who are still using 2D Pocket, instead of the new Dynamic path options.

[cruzila]

Sometimes it's about controlling an edge cut on brittle materials. Or maybe the pattern of the cut needs to be more squared off for the customer satisfaction. Maybe I don't want tool lift or higher feeds between stepovers. New is not always always better. Legacy paths are still valuable!! I would use 2d pocket more if I had that kind of start control. Actually being fairly new to MC less then 2 years, I was surprised this function was not already integrated.  Machining close to 40 years here, programming for close to 30.

[Colin Gilchrist]

31 minutes ago, altamontmfg said:

Sometimes it's about controlling an edge cut on brittle materials. Or maybe the pattern of the cut needs to be more squared off for the customer satisfaction. Maybe I don't want tool lift or higher feeds between stepovers. New is not always always better. Legacy paths are still valuable!! I would use 2d pocket more if I had that kind of start control. Actually being fairly new to MC less then 2 years, I was surprised this function was not already integrated.  Machining close to 40 years here, programming for close to 30.

Include a Chained Point, before your 'cut chain', and enable the "center on entry point" checkbox. That lets you put the Helix anywhere you want it. You get total control. Or use the XY Clearance, like I mentioned, to move the Entry motion towards the pocket center. But I think the Chained Point and Center on Entry Point, is your best option. 

What about "calculating where that entry point should be"? Disable the entry (temporarily) and let the Tool plunge in the material. Then run the Start Hole Toolpath to put Drill Operations at all the pocket entry points. Backplot and save those points as geometry. Fix the Pocket Entry to use Helix, and Center on Entry Point.

 

 

I get it; you've been machining a long time, and have a lot of experience. Me too. So I'm sorry if my suggestion wasn't what you wanted to hear, but I know how to optimize almost every path in Mastercam, the old, the new, and everything in-between. Sure, there are reasons to still use the Point Toolpath when you need the control, or even whip out the trusty Toolpath Editor to get what you want. Fortunately Mastercam usually has an option to give you total control over the tool motion. 

 

[JamesCNC]

@Colin Gilchrist,

Thanks for your great suggestions. I hadn't thought of calculating where the entry point should be by letting the tool plunge, creating a start hole operation, then running the backplot to find the exact starting point. I'm sure that might come in handy in the future.

To your point about using the Dynamic Roughing operation, this is my go to roughing strategy. Totally agree that it is a far superior toolpath for removing material efficiently.

The main use case I see for the 2D Pocket operation is finishing the floor of my pocket after Dynamic Roughing. The Dynamic Roughing operation can leave slight scallops in the floor and I often like to perform a finishing operation after.

I like the many pattern options the 2D Pocket operations it provides like spiral, concentric, circular, zigzag etc. for leaving an aesthetically pleasing finish on the floor of the pocket before contouring the walls. Even though I may only have 0.1-0.2mm of stock left on the floor I would still prefer to ramp down or helix down into the material rather than plunge straight into it.

Most of the work I do is one-off parts and going through the exercise of plotting the the exact starting point to then create a sketch with a point to start the helix is a somewhat lengthy workflow without great benefit.

I see that I can use the Area Mill to achieve a similar outcome but the machining pattern is limited to a single style rather than the multiple options provided by the 2D Pocket operation.

I think adding this simple feature to the 2D Pocket operation would be a great addition to the software to improve workflow.