MPMaster - Horizontal B axis Output Question

[Mick]

Ok, so I have a question.

I have a part, mounted on a fixture, and this part/fixture is mounted on the table of a horizontal (standard horizontal, with the B axis rotating about the Y axis of the machine).

I have a reference face/edge on the fixture used to set the rotation (this is a one off part being machined).  Operator has orientated the part by rotating B so the reference face is flat, and has set B0 in G54.

To post the toolpath out so that the B output is 0, I would expect to have the WCS/CPlane and Tplane all matching (its a newly defined plane, using the reference face of the fixture, and the plane orientated to suit the way it is sitting on the machine)

However, when I post it out, it returns the error "Select Machine Achievable Toolplane With Y Axis Along Machine Y - Set and Repost". The weird thing is, it is set correct, and if I set the WCS to Top, and the Cplane ant Tplane to the defined plane, it outputs the correct code, but with the B rotation of the amount that the defined plane is from the front plane.

This is using MPMaster right out of the box, and the machine def and post are set correctly for a HMC. Anyone else encountered this?

I've programmed plenty of HMC's before using MPMaster (earlier versions) and the above always worked for me.

[huskermcdoogle]

Front / Top ? 

[ajmer]

You will have to rotate the top wcs ( create a new one probably better) the amout of the face rotaition

Then use that as the wcs and use you plane as t and c plane

That should give you B0 output

[Mick]

It won't output B0 at all, and instead barks the error

ill do a sample file today and post it up to show the problem.

[mkd]

In my experience an untouched MPMaster will need TOP  FRONT/FRONT  to give you a B0.

in your situation with a face defined plane for B0, i would duplicate it and rotate it about X 90° to emulate "top" and set it as WCS.

[Mick]

2 hours ago, mkd said:

In my experience an untouched MPMaster will need TOP  FRONT/FRONT  to give you a B0.

in your situation with a face defined plane for B0, i would duplicate it and rotate it about X 90° to emulate "top" and set it as WCS.

That's what I have come to realise. But, to me (and of course, this is just my opinion), it doesn't make sense. TOP/FRONT/FRONT should indeed give you B0. But as long as the Y+ is parallel with the World Z+, DEFINED PLANE/DEFINED PLANE/DEFINED PLANE (WCS = CP = TP) should also output B0. At least, that's how it used to work, as far as I recall

[Mick]

Here is a sample file, and the image of the error returned.

 

In the sample file, the first toolpath group I created should (in my expectations) output B0 and the second group should (as it does) output the B index.

 

Horizontal Test.ZIP

[mkd]

2 minutes ago, Mick said:

That's what I have come to realise. But, to me (and of course, this is just my opinion), it doesn't make sense. TOP/FRONT/FRONT should indeed give you B0. But as long as the Y+ is parallel with the World Z+, DEFINED PLANE/DEFINED PLANE/DEFINED PLANE (WCS = CP = TP) should also output B0. At least, that's how it used to work, as far as I recall

I never understood the "logic" of setting up a horizontal machine in a different manner than an A rotation vertical. If you rotated about Y you get B. Rotate about X you get A. Simple.

 I do remember a forum thread from years ago on a method to get rid of the top/front thing.    thinking of you Colin

[gcode]

search for and uncomment this line in the post

#sav_rot_on_x = rot_on_x    #Uncomment this line to output rotary axis value even when it's not used

and see attached file

If you want B0 output, the Y axis of the WCS plane must be parallel and opposite  to the Z axis of the tool plane

 

 

B Axis Test_G_Code.zip

[Mick]

Ok... Got it.

Weird... But got it.

I have to be honest, I haven't had to look at programming a horizontal in this manner for a long time, and it seems things have change a bit since I did. Back then it seemed so much simpler

Basically it is a case of rotating the world gnomon about the Z axis.

Thanks for everyones input on this.

3 hours ago, gcode said:

search for and uncomment this line in the post

#sav_rot_on_x = rot_on_x    #Uncomment this line to output rotary axis value even when it's not used

and see attached file

If you want B0 output, the Y axis of the WCS plane must be parallel and opposite  to the Z axis of the tool plane

 

 

B Axis Test_G_Code.zip

My post already had the above line uncommented, but it didn't force the B output.

[Newbeeee™]

5 hours ago, mkd said:

I never understood the "logic" of setting up a horizontal machine in a different manner than an A rotation vertical. If you rotated about Y you get B. Rotate about X you get A. Simple.

 I do remember a forum thread from years ago on a method to get rid of the top/front thing.    thinking of you Colin

I believe the Hori posts went to Top/Front because then without creating any planes, you automagically get a B output just by using the standard FRONT BACK etc views.

If this is the only reason, I'd have kept standardisation at TOP/TOP between Hori and VMC.