Relationship between Setups and rest machining

[sprior913]

I'm trying to get comfortable with the CAM features of Fusion and there seem to be conflicting concepts with setups and rest machining.

The tutorials/videos seem to indicate that you would create a setup for each different bit you would use for a design, I believe some have recommended using the bit as part of the setup name.  But it also appears that rest machining will only work if both operations are in the same setup - unless I did something wrong the second rest operation seemed to start from the top of the stock when I put it in a new setup.

So I had pictured one setup for each bit, and then I'd select each setup and post process each into its own nc file.  But now it's starting to sound like a setup is strictly to represent putting a new piece of stock in the machine and you have to select sets of operations and post process them in groups by bit used.  If this is true, do I create folders under the one setup for the different bits used?

Can anyone either confirm or correct my understanding of these relationships?

[jeff.walters]

Your understanding is correct. Rest machining only works within a setup. I'm not sure why you would want to make a new setup for each bit just for posting sake. You can do all your cutting in the same operation (as long as they share the same XY plane and zero location), then simply select the individual operation to post.

[sprior913]

I think there is at least a documentation issue here, but also a missing concept that users are coming up with (wrong) ways to fill in.  Even the YouTube tutorials posted by AutoDesk personnel aren't teaching the appropriate workflow.

This very useful video uses two different bits within one setup, but since there are only two operations (each using a different bit), and he didn't show the post processing step it doesn't have to deal with the idea of creating 2 nc files under one setup that contain the paths per bit.

Patrick Rainsberry's awesome face carving video does try to deal with how you post process different files for each bit, but does so by creating two different setups which will break rest milling.

But I think that this confusion is built into the data model for Fusion's CAM.  The Setup has a post process tab where you specify what becomes the default filename for the nc file.  This works great when there is only one nc file to be generated for the Setup (one bit, or I assume a CNC with a carousel), but the only things that fall under a Setup are Operations and Folders.  A Folder however doesn't have a post process tab like the Setup does, so there's no built in concept that this folder is actually the level at which you are dealing when you are going to be post processing your operations.  For example in Patrick's video the right thing to do seems to be to create two folders under the one setup, name each for the bit used, and change its missing post processing tab to "rough" and "finish".  Then when you click on that folder and post process from there it'll guide you through what filename is appropriate for the nc file.

I actually think that the Setup/Folder/Operation objects don't clearly model the relationship between the concepts of CAM.  It seems in reality the hierarchy is:

- Setups which are placing a piece of stock in the machine positioned in a certain way

   - Uses of a particular tool within that setup (1/8 ball nose)

      - The operations using that tool in that setup (carve this pocket, then carve that pocket)

It's the middle level that's not clearly represented, and except for degenerate cases of a single bit it's the level at which I suspect post processing should be done.

Add to the confusion that the rest machining documentation and tooltips talk about the "previous operation", not the "previous operation within this setup".  Now that seems obvious to be now and it probably seemed obvious to the authors, but I assure you it is not obvious to someone trying to learn this.

I think at the very least there should be a section added to the concepts section of the help which explains this concept hierarchy.

Should I submit this on IdeaStation, or is this post sufficient?  Am I incorrect in anything said above?

[HughesTooling]

I think you'll find most people post all the cutter\bits in one file and change tools when prompted or they have a tool changer and just press the button on the cnc and walk away.

What you're talking about sound like how you'd work on a DIY machine where you can't change tools easily, if this is how you're working it more your problem than Fusions.

Mark

[sprior913]

Just because it's easy for you to change bits doesn't mean that the concept of operations grouped by bit isn't there (though it may be more of a time optimization for you).  When you start in the CAM workspace there is a box that pops up guiding you into creating your first setup.  It sounds to me like once you create that Setup and try to add the first Operation there should be another dialog that comes up and adds a grouping by bit.  When there is a concept missing in the operational model the problems start when the users try to figure out how to implement that concept in ways the system wasn't designed for, and that's what has happened.

And yes I am using a DIY CNC (actually an Inventables X-Carve), but that is a machine that AutoDesk has embraced and uses in some tutorial videos (both official and by people who just happen to work for the company), and if they are also having trouble setting up the proper workflow then I'd say it's not just me.

[Steinwerks]

You can post any order you want in a Setup, one at a time or not, but between Setups you're not going to get what you want without modeling it as the stock between them.

Your best bet is to program as if you were running a machine with a tool changer, post out every tool individually and leave your part set up, touch off the tool somewhere repeatable, and go from there.