HMC MD b-axis rotation issue

[Stuart C]

In the machine definition the B-axis zero deg position is set to z+ as it should be on a 4-axis horz with a b-axis rotating about y. The post is outputing the rotation from the WCS 0 deg which is x+. Changing the zero deg pos in the MDM is not affecting the post output at all. Am I doing somthing wrong here. Go Figure.

 

MILL 4 - AXIS HMC.MMD

GENERIC FANUC 4X MILL.control

GENERIC FANUC 4X MILL.pst

[Joe788]

I wasn't thrilled with the way the machine definitions and posts work in X/2/3 for HMCs, so I just ran the post update CHOOK for my old MPMaster from V9.1, and everything has been working great. I have it set as top view = looking straight at B0 side of tombstone.

[Slepydremr]

Stuart,

In your program are you originally starting from front view (which would be B zero) and rotating around what would be Mastercams Z axis but the machines Y axis? So that right side view would be B90 and left side view B-90?

 

Also when you are making toolpaths on different rotations make sure you're not changing the WCS to that new view only the T-plane/C-planes should be changing.

[Stuart C]

My part in mastercam is rotating about y. I transformed the part in mastercam to be the same as the machine CS. I was trying to avoid having to use a differant tool plane or wcs in Mastercam just to simlify things. Everything xyz) posts fine except the B zero deg pos which I can't get to change. What bothers me is I used MC's default config for a Generic HMC which is configured the way it should, changed nothing and the B rotation is wrong.

[Joe788]

Stuart, I'm still a little confused as to what part of your B axis rotation is incorrect?

[Guest]

Stuart,

 

It sounds like you might have been using a customized post previously.

 

Front plane IS default B zero, in Mastercam generic posts. Everything then rotates around the system Z axis for 90, 180, 270 and such.

 

If you're coming from the TOP as B0, then a generic post/MMD is going to have to be modified to work in that way.

[ken wong]

i have B zero at front c/t plane in defauld ,it should be at front like u guy say , so i confuse

[Superman]

Is your 1st toolpath done at the FRONT or is it done on the RIGHT side ?

 

I have had a situation where the post sets that 1st Op as B0.

 

If this is the case, then your post is faulty and will need modifying.

 

As a work around-

Try creating a dummy 1st op ( say, a spotdrill in space ) using the FRONT plane and then deleting it from your code.

[Stuart C]

Thanks for all the input but im still not there. Refer to my original post & reply. This is a fresh install of x3 using all mastercams default MD, control and post for a 4-axis horzizontal. I have edited nothing. The part is setup in Mastercam exactly as it would be on the machine. I,m in top plane & the CL of the part is the y-axis. XY & Z all post correctly. The B is 90 degs off. The B is posting with the zero point set X+ axis (default WCS) The MD has the zero point at Z+ axis which is correct.

 

So my question is why does changing the B zero point in MD not effect the output of the post. I've been using MC for a long time "V7" so I certainly know how to get this to work I'm just trying to get a handle on this machine def thing they started with X.

[Paul Decelles]

The MILL 4 - AXIS HMC.MMD is set up with the rotary axis along the world Z axis (where the FRONT plane is B0), not the Y axis as you are attempting to program it (with the TOP plane being B0).

 

I have modified the 4-Axis VMC Machine Def for your use. You can grab it here.

 

You will also need to modify the initialization of srot_z in the Generic Fanuc 4X Mill.pst to change the rotary axis label.

 

Change:

code:

---

srot_z       "C"     #Label applied to rotary axis movement - rotating about Z axis - used when use_md_rot_label = no

---

To:

code:

---

srot_z       "B"     #Label applied to rotary axis movement - rotating about Z axis - used when use_md_rot_label = no

---

 

[ 03-09-2009, 11:21 AM: Message edited by: Paul Decelles from CNC Software ]

[Stuart C]

Paul,

 

Sorry but I disagree. The mill 4 - axis hmc.mmd comes out of the box (I just installed X3 on a new PC to double check this)with the rotary axis set on y and the B zero point set on Z-. This is the correct setting for an HMC. This is how my part is set up. The XYZ values are posting correctly but the B is off 90. If I rotate my part (about Y) in MasterCam so the tertiary datum feature of my part, in this case a hole CL, is in line with the WCS x axis instead of z as it should be and is on the machine, the post output is correct.

 

So again, why is the post outputting the b zero from WCS X when the mmd is set at z and why, when I change the zero point in the mmd to something else is it not effecting the post output?

 

I'm working on the assumption that by changing the B-axis zero point in the mmd the post output should change as well.

 

This is a 5-axis drill toolpath on a cylindrical part using the 4-axis output format.

[Joe788]

Stuart, do you think you could post a quick screen shot with you part, and WCS displayed?

[Stuart C]

Paul,

 

Was going to try your modified VMC.mmd but our firewall is blocking you site.

 

Reason for restriction: Forbidden Category "Games"

 

Go Figure

 

I'll see if I can get our I.T. guys to unblock it.

[Stuart C]

Joe,

 

Classified part so no. Let me if if i can work up a dummy rep showing my issue.