Advice to tackle large foam part

[cshowalter1]

Hello all,

I am fairly new to programming high density foam and so far have had success, but I am struggling with the below part as it is more complicated then what I have dealt with so far. To my knowledge it will be machined out of one block of foam. My concern is regular 3D adaptive or pocket will not be enough to rough this out as the tool stays vertical, especially with the depth of this part and will crash the spindle. Also because of the size it is taking a long time to generate tool paths, is there a way to speed the process up? Any advice would be appreciated.

Edit: I should have clarified in my original question that this will be run on a 5-axis machine, and we have the manufacturing extension. My concern isn't whether the machine can physically reach the geometry, but what the best roughing strategy is to avoid head/spindle interference on a part this deep while keeping tool path generation reasonable.

Thanks,

[programming2C78B]

Why would you worry about the spindle? Just stick your tool out atleast 28mm

If you reduce the accuracy and increase the stepover, the calculation time will go down. 

[cshowalter1]

Because this part is 27.375 inches in height at some point there will be a conflict no matter the stick out.

[podging]

What tools and tool holders do you have that will allow you to go down even 1/2 the distance (13.5 inches)?

For speed do a rough calculation with huge stepover, make sure there is no collisions and it's what you want. Then do your actual toolpath with smaller stepover.

Remember to protect your finished toolpaths so you're not constantly regenerating them.

You can also increase the tolerance of your roughing passes but make sure that your tolerance is always lower than your stock to leave.

Break it up into multiple sections/depths.

Turn off all visual effects in Display Settings (who needs anti-aliasing) and shutdown all other apps, especially your memory hogging web browser.

Get a 2nd mortgage so you can buy more RAM.

[cshowalter1]

For tools and tool holders, we can get whatever is needed, so that's not really a limitation. The machine is a full 5-axis, so with the right programming strategy it should be capable of machining this part.

My question was more about the best CAM strategy for roughing something this deep without running into head/spindle clearance issues, rather than whether it's physically possible.

Thanks for the tips on speeding up the calculations.

I'll put the second mortgage right after I convince accounting that 64 GB of RAM is a consumable.

[a.laasW8M6T · Accepted solution]

You can try 3+2 roughing set to pocket mode

https://help.autodesk.com/view/fusion360/ENU/?guid=MFG-3-PLUS-2-STEPS

Fusion doesn't currently check against the spindle/table for collisions, but If you join the insider program you can try it out

[podging]

3-axis roughing as deep as you can.

Then switch to a 5-axis strategy. Since it's foam you can probably use a 3d surfacing strategy with 5-axis orientation and collision avoidance (maybe, you have more experience with foam than I do), or multi-axis clearing (which doesn't quite fit this part), or maybe the new 3+2 clearing toolpath (which I haven't tried out yet). And those are slow to calculate. The bigger the tool, the bigger the stepover, the faster it is to calculate.

Otherwise it's manually picking the angle, creating a bounding box, and then 3d adaptive.

Whatever you do, you aren't going to be able to do it in one toolpath. I have no idea how long that would take to calculate and I'm pretty sure that toolpath generation will crash before it's halfway done for a part this size.

[cshowalter1]

Thank you this worked and was able to generate as one path.