5 ax, center of rotation.

[savagkd]

Hi all, I have two 5 axis Haas VF6TR310s. The center of rotation is slightly different for each machine, and no dynamic offsets.

 

I would like to maintain one MCX file for each part. What is the best way to deal with the different centers of rotation?

 

I'm currently using two manual entry toolpaths to set G54 for all 5 axis, and Ghosting one or the other depending on which machine I want to run.

 

Is there a better way?... Post, WCS, Two separate files, etc.

 

All ideas welcome.

 

Thanks

 

Keith

[GIZMO 21]

We have a hass with a nikken trunnion,a few months ago i made a part that required milling on different

Angles.removed the nikken and i just ran the job again,so it caused my center of rotation to change.

Since i programmed everything incremental(linking parameters)all i had to do was move my part in my mcx file to the

New center of rotation and worked like a charm.

[Guess_who]

We use a 5th axis rotation macro setup in the machine, so the centerline of rotation doesn't matter. And the operator only has to setup one offset.

 

It will only work for positional 5th axis and not simultaneous 5th axis, but that's what needed most of the time anyway.

 

I know that's really didn't answer your question but I thought I through out the option.

 

 

Ray

[Eric@HorsepowerInc.]

We currently have 3 different 5ax machines, two on x one on y axis. We are able to run any of our parts on these machines even though they have different tilt pts. The CL should never change unless the machine has been crashed or the tilt pt was off to begin with. Using the same model/file this is easily done by placing a tilt pt. on different levels labeled for each machine. When you need to post for a different machine, you just move the wpc to the new point, change the machine def. if needed, regen, then your off making chips. That easy, been doing it for years.

[Greg Williams]

Can you use the post to add the rotation offset?

[DavidB]

Greg that's how I do it.

Just change the machine def in the ops manager and repost. Done!

[Eric@HorsepowerInc.]

Can you use the post to add the rotation offset?

Only if your post supports a offset for origin at the beginning just before posting. A few other things to think about, doing it this way you must also keep track of the rotation point for each part, we have hundreds, not doing that. Also if you keep the tilt point in the correct spot and don't rely on the post to calculate this @ posting, the numbers you see during verify are exactly what will be posting out. So if your like me and want a quick way to check something its easy to do by just backplotting the tool and looking at the actual coordinates.

[DavidB]

They all do Eric?

 

#Axis shift

shft_misc_r : 0 #Read the axis shifts from the misc. reals

#Part programmed where machine zero location is WCS origin-

#Applied to spindle direction, independent of RA

#Table/Table -

#Offset of tables to secondary axis relative to machine base.

#Tilt Head/Table - Head/Head -

#Part programmed at machine zero location-

#Offset in head based on secondary axis relative to machine base.

#Normally use the tool length for the offset in the tool direction

saxisx : 0 #The axis offset direction?

saxisy : 0 #The axis offset direction?

saxisz : -90. #The axis offset direction?

 

Dave

[Guyinthedesert]

Hi all, I have two 5 axis Haas VF6TR310s. The center of rotation is slightly different for each machine, and no dynamic offsets.

 

I would like to maintain one MCX file for each part. What is the best way to deal with the different centers of rotation?

 

I'm currently using two manual entry toolpaths to set G54 for all 5 axis, and Ghosting one or the other depending on which machine I want to run.

 

Is there a better way?... Post, WCS, Two separate files, etc.

 

All ideas welcome.

 

Thanks

 

Keith

 

Just curious, How far off are the tilt points? Since you only have 2, wouldn't it be easier to just regrind the table of the taller one and make them both the same?

[Aaron Eberhard]

You can always set up two different posts if your positions aren't changing, one post with the rotation center permanently compensated for Machine #1, and another for #2. You just have to be aware of which machine you're posting for.

[gcode]

Just curious, How far off are the tilt points? Since you only have 2, wouldn't it be easier to just regrind the table of the taller one and make them both the same?

I'd build tooling plates for both machines and machine them to the same pivot distance

[MIL-TFP-41]

I'd build tooling plates for both machines and machine them to the same pivot distance

 

^^^ +100

[crazy^millman]

Tom I would just machine the table on the higher one and done.

 

HTH

[savagkd]

Thanks for the replies.

 

Guyinthedesert, The diference in center of rotation is X.014 Y.020 Z.005 so regrinding the table won't help with X & Y.

 

DavidB, Are you using multiple posts, or machine defs?

 

I do appreciate all the Ideas.

[crazy^millman]

Wow that much difference I would use 2 different machine and control definitions that call the post made for each machine and be done with it. Let the post do the heavy lifting.

[Guyinthedesert]

Thanks for the replies.

 

Guyinthedesert, The diference in center of rotation is X.014 Y.020 Z.005 so regrinding the table won't help with X & Y.

 

DavidB, Are you using multiple posts, or machine defs?

 

I do appreciate all the Ideas.

 

.020 in Y? Sound like somethings wrong.

[Newbeeee™]

Not knowing jack about 5ax, could you use a combination of parameter changes to grid shift XY, and machine the table for Z?

For our 4x Chevalier's (4axis) we have made grid tables and have all machines grid shifted so any rotary goes on any machine and any program etc and all the datums are the same.

We did this as well for the Robodrills (XY) but couldn't do it for the Z as one machine is face and taper and the other isn't (boooohooo)

[jorges]

I do not recommend moving the geometry (hundreds or thousands of entities), like you guys said above it's better to create points to established WCS for each machine. Separate the points on different levels and name them accordig to machine being used.

It's better moving one point than many entities.

[Eric@HorsepowerInc.]

I do not recommend moving the geometry (hundreds or thousands of entities), like you guys said above it's better to create points to established WCS for each machine. Separate the points on different levels and name them accordig to machine being used.

It's better moving one point than many entities.

Exactly! never move the model, And I would never make two different fixtures to offset the Tilt point, so much easier and efficient to have 1 File with all that is needed to the make part in it. Additionally, what happens when you buy another 5ax machine that isn't a Haas? Your not going to build a fixture to make the tilt point the same as the haas! You just add another level that says xxx machine tilt point, and done! I do agree something is wrong with your center of rotation, I would indicate this again, your only difference should be in the Z on a single platter 5ax. We have a Vf5 with a TR160-2 dual platter 5ax and set up properly their is no difference in Y only in the X and a slight difference in the Z axis. Even so we can still remove these fixtures place them in our Doosans with a Komo trunnion and have a program posted within minutes. I personally would never make additional work for your self, keep it simple, 1 fixture that mounts to a master that can go on any machine, and 1 file to keep it un-cluttered.

[DavidB]

Thanks for the replies.

 

Guyinthedesert, The diference in center of rotation is X.014 Y.020 Z.005 so regrinding the table won't help with X & Y.

 

DavidB, Are you using multiple posts, or machine defs?

 

I do appreciate all the Ideas.

 

Yes just change the machine def in the ops manager to the machine you want to post too.

Each machine def has its assigned post.

 

That way you can see which machine your posting too.

[savagkd]

Thank you all for the info. I think I'll go with 2 posts/MD/WCS.

 

You gotta love this forum. Throw out a question, roll around in the mud with all the ideas and walk away with something that works.

 

Thank you all!!!

[Bob W.]

Wouldn't it be possible to write a macro that calculates and moves the work offsets during indexing? This way the machine could be run like it has dynamic fixture offset. This would work great for 3+2 or 3+1 but not full 5-axis.

[crazy^millman]

This would work great for 3+2 or 3+1 but not full 5-axis.

 

Bob so you would then program parts one way some of the time then other parts a different way some of the time? Again getting back to the post and machine and control definition you ensure you program the same way all of the time.

[Guyinthedesert]

Wouldn't it be possible to write a macro that calculates and moves the work offsets during indexing? This way the machine could be run like it has dynamic fixture offset. This would work great for 3+2 or 3+1 but not full 5-axis.

 

I was thinking of something like that, not as a macro but just as a stand-alone program that would re-calculate all the x,y, and/or z values based on an input offset. No reason it wouldn't work for full 5x, the actual math behind it is all jr high school algebra.

[GoetzInd]

Put me down for the post mods. MP is very powerful and can do a lot cool stuff. I'm just not the one who can make it do it

 

Mike