Cuttin' chips - main body - adaptive, profile and pencil toolpaths

Make some chips finally!

Sod it. After losing several days messing about with the Renishaw probe, I'm finally in a position to be able to machine this damned bracket. I done got me a damned fancy cutter and generated all the toolpaths. Although I have no guards and this will be messy, nobody will die if they get a bit of coolant and swarf on them, so off we go.

Face milling the top surface:

First face it off with the Korloy 50mm face mill. I did this dry at ~980rpm. Interestingly, the machine correctly selected low ratio and drove the motor at just shy of 6000rpm to do so. So it all seems to be doing what it was intended, although I must admit I couldn't have told you that was all working. I must have done something right.

The finish wasn't startlingly good but perhaps if I'd used either WD40 or flood it would have been a lot better. As it is, this is cold rolled steel (CRS), so the skins is probably a bit tough. Doesn't matter a great deal, as very little of this top surface will survive beyond the first few ops.

2D Adapive - roughing out the main body:

Then the big test of the (expensive) new cutter. Needn't have worried - it flew through the metal, producing a fine stream of clean chips. Was a little noisy to start with but there again I was pushing at bit given the state and vintage of my machine.

Cleaning up - 2D Contour:

Then the 2D Contour, to clean up the external profile. I have to say this came out really well. The only vague issue was a "chirping" that came when the 12mm cutter had to generate a 6mm radius fillet in 4 places. There wasn't much it could do about that - it's more down to lousy design and tool selection. I knew this would be a bit marginal but I didn't want to reduce the radius any further, yet I wanted to use the biggest (most rigid) tool I could get away with. The bottom line is - the final result is excellent.

Then chamfer the top circular edges. I created the CAM on the PC in the workshop, loaded the tool and ran the g code. Quick and easy.

Forming the fillet - pencil toolpath:

Finally, used a Pencil toolpath to clean up the fillet which was left with a stepped profile after the roughing op. I defined a 6mm ball end mill / holder etc, generated the g code and posted it.

Although technically the ball end mill is for loominum cutting, it was fine here. I simply dialled the speeds and feeds down a bit - 6000rpm and 600mm/min. Having said that, it didn't hang about! There was actually a nominal 0.5mm axial stock left by the 3D Adaptive, so in fact it took off a bit more than I'd expected - but only what it was programmed to do! Nice finish. No suggestion of a problem.

I think that's it for this particular setup. Now I will remove the workpiece and remount it for the next operations. I should save the current solid and use it as the stock for those.

Saving the workpiece as a solid:

You can save the simulated workpiece as a solid and then import it back in, for use as a stock model for subsequent operations. You might argue that "rest machining" might accomplish that but I don't know if you'd be 100% right.

There have been a few Youtube vids showing how to do this. Here's one that is short and to the point. Slight issue here being that it didn't work for me. I suspect Autodesk have changed something. 

This is what worked for me:

1. In CAM simulation, save the "finished" model as STL. Right click > Stock > Save stock. You don't seem to need to specify the file / model type.
2. Change to the Fusion Model environment, import the STL by selecting Insert > Mesh. Rename ("Stock body" etc), as required. NB: Ideally, open a new file to do this - you must turn off the timeline for the "STL to BRep" option to appear in the Model environment.
3. Reduce the size of the STL file (in the Mesh environment, Modify > Reduce). I reduced it to 0.05 (ie 5%) of original and it lost very little noticeable detail.
4. Convert from STL to BREP: Modify > Mesh > STL to BRep. You now have a solid body.
5. Import this new body into your working file from the Data Panel: "insert into current design".
6. In the CAM environment, you can now select this body when specifying the stock for the next operations.