WCS completely ignored.

[mcguy39]

Hello folks.

This here fusion 360 is driving me up the wall. I spend 90% of the time fighting the program and all its "can not compute" and other error messages during design.

Some time I feel like I'm back in the mid 90's the way one has to painstakingly point out all the 50 points to be used and stuff like that. Also not intuitive at all.

And now, I am trying to machine (mill) a couple of really simple, small items a seen here.

Really simple, right. I could do this in my sleep by hand.

But theese "intelligent" programs cant.

As you see here in pic 2,

Pic2

the WCS is set in the corner.

Then I would like the cnc mill to countersink, and here i use 3d contour command, and make the holes, using the bore command.

And here, s.. hits the fan for real.

As you see here

The tool decides to start in a completely different location, totally ignoring the WCS start position down in the corner.

The 2D "Bore" command does the exact same thing.

Now, I also need to cut theese two pieces from a flat piece of sheet metal, so it's important that the tool zero position is at the same position all the time.

The cutting is set up on a separate "job" since I have to change tool between theese operations. And the tool zero on that is at the very same place as I asked it to be in the setup file. Down in the corner. No problem. For cutting I use the 2D contour command. No problem.

The thing is, why the heck does fusion 360 ignore the countersink and the bore???

Earlier I have done both cutting and bore in the same operation, and have never seen this problem before.

Is this yet another thing Fusion 360 cant do???

[Anonymous]

@mcguy39 

If you could please upload the file that is giving you problems, go to :-

File > Export > Select f3d format > Save to a location on your computer > Then attach to your next reply.

FWIW I am perplexed, the WCS has really  nothing to do with where the toolpath actually starts, it just makes the toolpaths relative to that point for code generation so that you have a point of reference to take to your CNC machine for stock setup at the machine so that when you setup to that same corner of your stock at the machine then all the toolpaths will be cut at the correct position reletive to that point, there is an option under the "Links" tab for most operations to set an actual "Start Point", looking at the countersink toolpath in you image they do seem to be fine as it is doing them in order and not jumping back and forth, if you want the countersinks to start nearest to the WCS shown then just reverse the order they are selected in.

[mcguy39]

Thanks for answering.

Well, that refence point is exactly what I need. I guess it could be possible to set the ref. point to the center of one of the holes too, but that complicates the setup of the mill, so a ref. point in that corner is by far, preferable.

I have to add, though, that I'm still kind of a newebie to Fusion 360 and all its bugs, and even more to CNC milling. So I guess all the techical terminology is above my pay grade at the moment.

Anyway, I attach the file. It mught be that the model loads z axis down since I have re-oriented the top, but it should be reasonable understandable.

[Anonymous]

@mcguy39 

Not so much bugs, more a case of learning the ways that Fusion does things, see the image below, now all the hole toolpaths star nearest the WCS which I have actually moved to the corner of the Stock, that way it is easier for you to just select the corner of the actual Stock on the CNC machine, where you had it you would have had to setup at the machine and then change your probe settings in the control, much easier how it is now. Updated file attached, have a good look through the settings used for future reference.

In this first image I have both toolpaths starting from the same position, in the second image I have set the second toolpath to start at the furthest away, reason, you have the same tool for both toolpaths so rather than the machine doing all the holes once and then moving all the way back to the beginning it can start at the last hole done and work backwards, save time and wear and tear on the machine.

 

Hope that is of some help to you, file attached.

[daniel_lyall]

The first toolpath set the entry postion to the hole closest to the first hole, 2nd toolpath as has been said reselect the toolpath in the order you want the cut done.

It would help you a lot if you go through this https://help.autodesk.com/view/fusion360/ENU/courses/

[mcguy39]

Thanks a lot guys. I was also fiddeling around with a start postition to be in the same hole for both operations. That's not so hard to do. The problem is, though, after the countersink and holes are done, I need to change tool, load another file and cut it.

That operation has a zero point in a corner, and that is the position i have to zero the mill after.

When I do that, then load the countersink/bore file, btw, I'm using Candle at the moment. Not the best program but I think it's simple enough that it is easier to learn from, for then to go to Mach 3 or 4.

So, when zero is in a corner, that same corner is in no way used as a reference point for the first grbl file, doing the countersink and the bore. So I get those in the completely wrong place.

Also, when I was messing around with using a center hole as a reference, I saw that the starting point of the tool was NOT in the center of the hole if I started with the countersink, so I'd have to start with boring, then countersink.

I guess it would be doable that way, but not intuitive at all. And quite cumbebersome. MUCH easier to have a universal zero in a corner.

On top of everything else, I still have to make another path again to make a 45 degree edge on the opposite side of the countersink.

A common zero for all of this would make the whole operation so much easier.

Maybe there is another program that can do this better?

But I'll mess around a bit more to see what can be done, I guess.

If worst comes to worst, I'll have to settle for a center hole zero.

Thanks again for the help.

[mcguy39]

P.S.

On closer inspection, using a hole as a reference won't do either. The tool path does NOT start in the center of the hole in either the boring or the countersink operations. And since I have very small tolerances, it simply won't do.

Then only one thing can be used. A corner reference to start the tool path from. The same on all operations.

Or, I simply do it by hand, since my time and patience is limited.

Good for making theese parts only, but not for replicating. That's the sole reason for using a cnc mill. Or a 3d printer for that matter.

[mcguy39 · Accepted solution]

Seems like the problem has been solved. In a weird way, but still. Havent tried this on the mill yet, but a test load in Candle indicates that the zero position now is in the corner I wanted to.

It was simply to change places of the two operations, to put the bore action first, then the countersink.

For some reason, since the bore command I use is 2D, it seems to put the zero tool position in the corner of the workpiece, something that the 3D countersink can't do.

Does not make a whole lot of sence to me. And it's an unessesary feature.

I think one SHOULD be able to set a zero tool position to anywhere one find most usefull, regardless.

Maybe it's possible, but I have yet to find a way in Fusion.

Anyway, problem solved, I hope.

Thanks again for helping, folks.

[Anonymous]

@mcguy39 

I am thinking that you are going round in circles and still not understanding the difference between what you do in Fusion and what you do at the machine.

In Fusion you can place a WCS (Work Coordinate System) point anywhere in your Fusion setup, but you just need to remember to use the same point on your Stock material so that they match up.

So if you use the lower left corner in Fusion then at the CNC Machine set your "touch off" point to the same lower left corner.

That`s all you need to do to match them up !!

Tool Z zero has nothing to do with Fusion, that is something that you have to setup at your CNC machine so that the CNC Control system has the correct information to enable it to cut the program in the correct position and to the correct depth. All you will get in the G Code will be a tool number eg T1 and a length offset of H1, these command call up the information that you have in your CNC Machine Tool Library not in Fusion.

Tool lengths and Diameters set in Fusion are NOT used by the CNC Machine, they are for use by the Fusion Simulation so the user can see how the part would be cut and what it would look like after cutting

[daniel_lyall]

@mcguy39 It would help you a lot to learn about what each part of cam does from the setup to the machine in the link I posted above you will find most of this stuff I use a machine running cncjs I don't use it any differently than I use a machine running mach3, 4, linuxcnc soon to be path pilot.

If you need to do a new setup and it is the same model on the same side duplicate the setup.

[mike.mattera]

I know I'm a bit late to this dance. But I'd like to offer some information on the topic of Setup and WCS.
There are 2 videos below that might help.
https://help.autodesk.com/view/fusion360/ENU/courses/AP-TOOLPATH-SETUP
https://help.autodesk.com/view/fusion360/ENU/courses/AP-SETUP-2ND-SIDE

But I would suggest going thru the entire series. No telling what other important things you might pick up

https://help.autodesk.com/view/fusion360/ENU/courses/AP-C-FUNDAMENTALS-OF-MILLING