X Y Z positioning after B axis rotation

[britovsekmatic128]

Hello,

i am trying to mill a simple groove with B axis but after rotating the B axis xyz arent in correct  position.

the xyz are almost in the middle while the workpiece is cca 250mm to the right(See picture)

Have i choosen the tool rotation options wrong or should fusion output a dynamic offset or do i have to somehow compensate the rotation from the middle of the table or is something wrong with the post processor?

The machine i am using is a 4 axis horizontal with fanuc 31i

Thanks!

[engineguy]

@britovsekmatic128 

With the Setup set to the center of the stock so it rotates around the B axis I get different coordinates, see images below for you to compare, first one is your original code and the second is mine using the center of the stock as the WCS rotation point. If you have the block of stock set with the back face aligned with the center of the B axis then you should set it the same in Fusion, where are you setting the WCS for the stock in your machine ?? See fourth image

You can set an offset in the Post Processor in the Machine Configuration section, see below.

[britovsekmatic128]

hi @engineguy 

the offset is basically on top of the workpiece like on my model.

I was thinking to make a point from the current WCS move it ((Z-797.359)picture attached)
and select that for my tool orientation WCS.

Sorry i dont understand you about the post processor can you explain further?

[m.britovsek]

hey @engineguy  

I tried to move the tool orientation origin to the bottom of my model and also into the middle of the table but fusion outputs the same code no matter where the origin is.

[m.britovsek]

Any ideas? Pretty sure it has something to do with the post processor

[engineguy]

@m.britovsek 

I am confused, in your image you show the Tool at an angle to the Z axis, is your Horizontal a simple 4 axis with th B axis rotating around the Y axis as in the image below ??

Is it Z in/out with Y up/down and X left/Right as in the image or does it for example have a tilting head ??

Are you just working from the Table or are you using a "Tombstone" ??

[britovsekmatic128]

Hello @engineguy 

It's a horizontal milling with 4 axis as your picture shows, with b rotating around y.
There is no tilting head and the workpice is on a fixture attached to a tombstone.

[engineguy]

@m.britovsek 

OK, is it like the image below ?

If so then that is how you draw and set up using a Tombstone, all the X/Y/Z/B values will be correct, you just need to set the WCS to the same place in both Fusion and at the machine.

Setup image and sample code from this setup below.

Example file attached, just for information 🙂 🙂

[britovsekmatic128]

Thanks for the help @engineguy and sorry for taking so much of your time.

So basically i need to set the WCS in the middle of the table?

[engineguy]

@m.britovsek 

You can set it anywhere you like, the main thing is that you have your Stock in Fusion and in the Machine in the same place so if you want to use a corner as in the image below then you must Probe that same corner of the Stock in the machine so that the machine Control knows exactly where that corner is located reference to your rotating axis, then the code generated by Fusion will cut the Stock correctly. The code from the image below is in the second image.

[britovsekmatic128]

I tried moving The WCS multiple times and on diffrent places but i always get the same coordinates

[engineguy · Accepted solution]

@m.britovsek 

If you place your Model as shown in the images that I have uploaded and select different point for your WCS then you will get different G code, I have attached the G code generated with the WCS in the center of the Table and on the corner of the Stock as in the two different images.

You must setup your tombstone/fixture/model/part as it will be setup in your machine, after that it is easy, G code files attached for you to compare.

Make a model of your Tombstone and fixture as I have shown to the correct sizes as the Tombstone on the machine and you may then be able to visualize things a little better 🙂 🙂

[britovsekmatic128]

Thanks for the help.

I will try doing it tomorrow on the job since my F360 expired yesterday.

[britovsekmatic128]

Many thanks @engineguy !

Moved the WCS in the middle of the rotaion/pallet and it works perfectly!