Tool Orientation Troubles

[Aaron34NGQ]

We're trying to get a lathe set up for counterclockwise spindle rotation with the tools facing down. I can't get it to work properly with my custom tools. If I use the sample tools (set up for clockwise) the animation looks like it's set for CCW. If I set up my tools for CCW they error unless I set them to left handed. What am I doing wrong here?

[tony]

Yeah I can get fusion to work with it CCW but like you said the post or code would have to be changed. I don't like editing code by hand for something as generic as this that could cause problems. I guess I'll have to modify the post. I'm sure I can just substitute M03 for M04 and vice versa?  

[mike.mattera]

A simple rule for finding CW/CCW direction. This applies for spindle direction and rotary axis rotation direction.

You should always view rotary direction by standing on the Positive (+) side of the center line axis, and look thru towards the Negative (-) direction.

X Y Z   The Linear Axis of the machine

A B C   The corresponding rotary axis

In this case, standing on the Positive Z axis position, and looking thru towards the Negative Z axis direction, we can properly view the spindle direction.

[tony]

Mike 

Do you have a digram base on the example you mentioned. I spoke with the manufacturer of the lathe and the way the machine is configured right now is their correct convention with M03 Spinning away from the operator. 

[mike.mattera]

I do, but not on this computer. I plan on posting it as soon as I find the diagram.

A right handed tool, on the back side of the spindle (away from the operator) should rotate the spindle CW (M03).

The insert face is pointing up.

A right handed tool, on the front side of the spindle (closest to the operator) should rotate the spindle CCW (M04).

The insert face is pointing down.

[Anonymous]

The picture posted by @paul.clauss (below) and the statement of @mike.mattera

"You should always view rotary direction by standing on the Positive (+) side of the center line axis, and look thru towards the Negative (-) direction." are kind of the opposite?

At the positive side of Z there's the tailstock. Now I stand at the tailstock and look towards the negative side of Z, the head stock. If it now clockwise turns clockwise (like it should with M3), it is the opposite of the picture below..

@mike.mattera are you sure??

Regards,

Daniel

[mike.mattera]

Unless that's for a specific machine, I'd say that diagram is wrong.

[LibertyMachine]

I've not run a lathe in many years, so take this with a grain of salt, as the memory fades over time...

On CNC lathes, the tool is mounted upside down so all chips are directed downwards to the chip conveyor. Thus, the spindle would be rotating towards you, not away. M03 would be the command to use, iirc. Doesn't that match up with the image?

[mike.mattera]

I haven't run a lathe for a span of time longer than you. 🙂
So, yes, I could be wrong.

[rhdfmail]

The lathe I'm starting to get up and running does at the moment have left-hand tools mounted in Turret1, wich is "behind"  the spindle. That means , if I'm correct, that I have to run the spindle CCW. But fusion dont let me do that

(sometimes it feels that the software are a bit too helpful...)

[seth.madore]

In the tool library you should have the option of ticking the CCW option:

[rhdfmail]

To clarify. Yes I can change between CW and CCW, but then the tool changes .. or changed, when i tried today it didn't .. probably one of those strange fenomen that pops up now and then and you never know whats going on

[tomae]

Seeing this thread makes me laugh ...  and cry.  In Oct of 2015 I raised this issue.  I submitted it as an idea in Oct, and raised it as an issue later again when that got squashed due to lack of votes.

Not ALL lathes adhere to your idea of tool orientation and spindle dierection.  Who made that descision anyway?  Our Emco (120P) lathe allows tools in the turret to be placed either forward facing or backward facing and those tools can be left or right hand tools.  It works great in spite of Fusion’s instance that it is somehow wrong 😉

I asked that spindle direction and tool orientation be decoupled back then, or at a minimum allow one to turn it off and define their own direction!!  I hand edit every post because Fusion will not allow me to define, for example, my left handed threading tool which is turned around backwards in my turret with the spindle spinning M3 while my right handed profiling tool is also backwards but spinning M4.   

https://forums.autodesk.com/t5/fusion-360-ideastation/additional-lathe-tool-orientations-and-correct...

https://forums.autodesk.com/t5/fusion-360-computer-aided/please-decouple-spindle-direction-from-tool...

-Tom

[Anonymous]

It seems to me the only confusion here is about "what is CW and CCW".

As described in user manuals by machine tool builders, in every one I ever opened it clearly states that CW is direction of spindle rotation as seen from back of the spindle.

With that sad, cutting edge of a right hand tool points down in block and spindle turns CW (M3) to produce a cut.

If tool block allows to mount the tool in reverse, so that insert points up, then with that change comes making spindle rotation CCW (M4) to produce a cut.

Now, if you stand in front of the machine control looking at a spindle on your left side, everything stated above reverses its meaning.

As for left and right hand tool holders, I can use anything that works to clear obstacles and execute desired tool path, so long as I follow with correct spindle rotation to make a cut.

To look at CAM system to predict and accurately accommodate for all possibilities is a bit too much to ask, and here is why.

Using right hand boring bar oriented as turning tool (rotated 180 degrees) it is perfectly normal to cut right hand threads on OD of a part by starting each pass from shoulder and feeding towards part face while driving spindle in CCW direction,..... or cut left hand threads by feeding same tool from face toward shoulder.

I don't think it is primary focus of any CAM system to provide solutions for "off the chart" techniques used every day to remedy lock of other options or simply not having right tool available at the moment, although if I am repeating same tasks, tailoring post processor to minimize edits after posting would be good idea. 

So it comes down to this, right hand / left hand, CW /CCW ..... it all takes on different meaning if universal principles are not considered to begin with.

If I stand on my head, world appears up side down, solution seems to be to not stand on my head.

In any case, driving spindle in wrong direction is one step away from learning how to weld using CNC lathe, and the lesson will be over before you reach for E-stop.

[rhdfmail]

Well, the problem is, as stated, when what works in reality isn't possible to acieve in software
If I have a lefthand tool in my "upper"  turret on a machine that obviously has ben running programs that way I want to be able to program  for that setup instead of having to redo all my tooling to fit what some developer thougt was a good idea...

[tony]

I agree. Why is it so difficult to just have an option of telling the software which way You want the tool oriented. I have two lathes now and an m03 on both spin in two different directions from each other. I know everyone says there is a standard convention of which is the correct way but machine builders can make a controller turn the spindle which everway they want weather or not it’s to a conventional standard. 

[rhdfmail]

My first program for this machine will be a simple program that runs both spindles very slow in each direction to see whats M03 and  M04 😉

Just the thing that primary spindle is no 4 and secondary is no 3 is something that makes me think i'm going to get some suprises on the way..

[tomae]

Software should help people obtain their goals, not get in the way of them.  I understand the need to make some standard the default operation.  

As we say, the beauty of standards is that there are so many of them 😉

I really do not understand wanting to prohibit the option to do something else.  Provide an option to decouple tool orientation from spindle direction, Please.

-Tom

[tony]

Tom

I 100% agree with you. At least give the option in the software. Once you get your machine and post configured correctly it will not be an issue after. But not being able to change the orientation to match spindle direction is super frustrating. 

[rhdfmail]

sometimes it feels that fusion360 is a bit TO user friendly, as in: prevent users from doing "misstakes" that isnt misstakes . Its stuff people do because we know what we are doing to get the job done. 

[Anonymous]

Let me tell you how I approach any lathe work, knowing what that lathe can and cannot do is critical before starting the project. I study the part requirements to determine best way to program it but program is not the first thing I do.

First thing I do is take close look at how to mount tools, what their purpose is, can I accomplish what I want in one or two operations, maybe more.

Tooling available at the moment determines how I can handle the job, after taking the assessment or even mounting tools first to see if there are going to be any obstacles that need to be considered, I can start programming the job.

Note that CAM, hand input or combination of both is last phase in the process.

Unlike programming mills, lathe work is very finicky about many particular details, mainly because we don't have interchangeable turrets with preloaded tools for particular job. When any of the tools run, I must be sure that tools next to it on both sides will not collide with jaws, sub spindle, lower turret or machine guard behind spindle.

None of this can be predicted in CAM software therefore software does not determine how I program and run the lathe.

On top of that we have multiple brands and sizes of lathes with one thing in common, they are all different and special in one way or another, they don't share 5 feet of empty space around spindle like mills do.

Sure I can mount virtual tools and simulate process but all that work is wasted time since I must physically copy  any parameters in actual machine set up, therefore why not start with that in the first place and do the programming after all is cleared and checked against potential error.

At this point determining whether spindle should be spinning CW or CCW for any of the tools is simple matter of visually confirming each tool before cutting.

Basically, no matter what the arrangement and  orientation of tooling, spindle must spin in direction of cutting edge to produce a cut on contact.

I can still use any CAM to produce valid code, ignore tool orientation and spindle direction but adjust it at the machine while proving the program.

I think people are putting too much faith into CAD/CAM system and asking it to do the thinking in all phases of machining.

With all of its sophistication, CAM is not artificial intelligence, it only does what we tell it to do, we must do the thinking and make rational  decisions, subsequently automating some of the processes to simplify process of repetitive tasks.

I have yet to program any job in CAM system that can be fed directly to machine and run without any edits at all.

I am sure it can be done, it's just not the way world runs.

In a typical shop, programmer puts out main tool paths to accomplish desired goal, set up person mounts tools and dials in the details, often scrapping parts of the program and typing in new code at the machine to correct mistakes or simply make more efficient cuts.

In my 30 years I worked mostly as programmer/machinist, handling complete job, programmers with certificate and mediocre machining experience were nightmare to deal with because they had no clue as to what they were doing.

Simply stated, CAM does not make a programmer, machining experience does, and from that perspective I do what logic tells me to do.

If CAM cannot produce results, there is always the old way, step by step manual programming with understanding that programming complex tool paths can be a hear pulling experience even with canned cycles that can accomplish nearly anything that needs to be done.

I use Fusion or any other CAM with reservation, always on the look out for errors in code because what I see in simulation is not necessarily what post processor will duplicate, I back plot everything before running it.