Post Processor doubt

[maluv888]

My VMC machine has 4th axis but all 4 axes cannot run simultaneously. any 3 axes (x,y,z or x,y,a or y,z,a or x,z,a) can run simultaneously at a time. how to edit a post so that it uses 4th axis but outputs code in such a way that only 3 axes run at time ?

[Anonymous]

@maluv888 

Text below assumes the A axis in line with the X axis of the CNC

That will be a fairly normal setup, often some older CNC controls use what is known as "Swap Axis" and will depend mostly on how you choose the operations to perform on your parts, a pocket indexed to one side of a part will only use the XYZ axis for cutting after the A axis has positioned the angle for machining, a wrapped pocket would likely just use the XZA axis, drilling only the Z axis, the XYA will do the positioning.

There will not be many operations you will not be able to do, for example a Multi Axis "Rotary" toolpath will likely have the A axis rotating with the Z axis moving up/down and along the X axis.

No reason I can think of to try and change the Post Processor ?

If you can upload a Fusion file that you think is a problem then someone can take a look for you

[maluv888]

you can click on below link :-

https://www.youtube.com/watch?v=LVhiJfkMB4c

my job is also a spiral bevel gear, similar to the one mentioned in the above link.

[Anonymous]

@maluv888 

Something like the images below? First one is the Model imported from Grabcad and the second one is the Fusion simulation of the model roughed out, the stock solid is only a rough representation just to give you one idea of how you can go about the job, there are plenty more

I created a Solid stock because I would have machined the basic shape on the Lathe, you can change the stock to a "Relative sized cylinder", just means a lot more machining time.

Done with simple 3D toolpaths (3D Adaptive and Parallel) and a Circular Pattern for each so I only did one tooth just as in your video link, there are plenty of 3D toolpaths to choose from for Finishing, all 3 axis motion and the 4th (A axis) will. just index to each position, I have attached the example file for you to "play" with !!

[maluv888]

Hi,

Can you please try programming the attached file ?

[maluv888]

i am waiting for your reply to my yesterday's message . did you open and see my model ?

[Oliver_Bentley · Accepted solution]

@maluv888  Something like this?

[Anonymous · Accepted solution]

@maluv888 

If you are going to mount your 4th axis at an angle as @Oliver_Bentley  has programmed it then that will work fine, however if you have the 4th axis mounted at 90 degrees to your table then due to the shape of the teeth you will need to rotate the part so that for example the right face is fully machined and then to do the left face you will need to create a second part (just duplicate in design) and rotate that far enough in the opposite direction and use that solid for the stock in the second setup.

The easiest way for programming is obviously to mount your 4th axis at the angle needed and run similar toolpaths as @Oliver_Bentley  suggests, due to the shape of the bottom of the teeth you will have to do some Math to get the angle accurate otherwise you could end up with the shape of the teeth not mating up correctly with the corresponding pinion that will be used.