Multi axis trace / chamfer

[Anonymous]

Hi everyone. I'm new to Fusion (Legacy) and have been searching the forums on my slow internet which is taking a long time. I'm trying to get this figured out before I lose any more hair. I have a couple issues. I'm trying to multi axis contour what will be a chamfer on a plug. The simulation does not follow the complete path and the tool top does not appear to be running perpendicular to the path. The part is going to be mounted on the trunnion table with my A axis tilted at 90 deg and the B will do the rotation about the Y axis. The other issue is: is there a post processor for an old Haas with a trunnion  table? 

Thanks

[engineguy]

@Anonymous 

Can you please upload your Fusion file, it is a huge help if folks have a file to work on.

To upload your file have the project open in Fusion, go to >File>Export>save as f3d format to a folder on your PC and then attach the file to your reply post.

Regards

Rob

[Anonymous]

Rob, 

Thanks for the reply! I've attached the file. Please note that the edge to chamfer does not have that feature shown on the model. My thought was for simplicity, just keep the geometry simple and trace the contour with a ball mill. I have a trunnion table with the rotary axis as B (rotates about y ) and the tilt axis  as A (rotates about x ). 

[engineguy]

@time1PFUMH 

I fully agree with you on simplicity, many, many years ago as an apprentice it was hammered into me (sometime literally) to alway "KISS" (No, not the rock band) everything which turned out to mean :-

Keep

It

Simple

Stupid

Never forgot it 🙂 🙂

So having that in mind I came up with this little program which seems to work OK and only needs a simple 4th axis we hope 🙂

Does this do what you want??

Fusion file attached

Regards

Rob

[Anonymous]

Rob,

That's exactly what I was trying to do! Thank you so much. I'm tried duplicating what you did on my original file and it worked too.  Hopefully, I can get it to generate a good code. Here's part 2. Are you aware of a post processor for a Haas Mill with a trunnion table with a B rotary axis and A tilt?

I'm also a big fan of the KISS method. This was something driven into my head while earning my Mec. Engineering degree. 

Thanks again for the amazing support! 

[engineguy]

@Anonymous 

Sorry, I forgot about your PP, yes, there is a HAAS Post Processor that will output the B axis moves you need, whether your control will accept the code from it is another matter, it is the HAAS Next Generation PP, it is multi axis.

I have zipped up the PP and attached it here for you, I have generated code here and if the B axis is selcted when you come to generate the code then it does indeed produce movements in the B axis so if you have your B axis in the Y axis and the trunnion moving in the X axis with the trunnion locked with the B axis vertical as per your model then it should work for you fingers crossed 🙂 🙂

Regards

Rob

[Anonymous]

It did spit out a code. Hopefully the next gen processor will continue to work on this older machine. I'm trying to wrap my head around this one. Initially, to keep it simple, I was thinking the code should have one Z depth on the part, a linear motion in Y into the part, followed by a series of B rotations and Y movements out of the part. I'm looking at the code and I have X,Y,Z and B movements. Maybe it's because the chamfer tool is on the inside of the contour. Do you think if I for example, run a ball mill on the centerline of the contour this would eliminate the X axis movements and keep a constant Z depth?

[Anonymous]

I ran a dry run in the machine and noticed that the axis weren't moving as per the simulation. So, I changed all of the negative B movements to positive numbers and all of the positive B movements to negatives.....its looking better. Just have to figure out how to modify the post processor to reverse the B axis movements.

[engineguy]

@Anonymous 

Sorry for the delay getting back to you, domestic chores got in the way 🙂 🙂

OK, looking at the code as generated here using that HAAS Next Generation PP it appears to be correct to me, because the first contact point is not at Top Dead Centre and is to the Positive direction looking from the rear of your B axis then it is moving in a clockwise direction which I would expect to be the default direction of your B axis, if it is not then you should be able to change that in your HAAS control parameters.

So the first move to start position is 16.255 degrees and then it moves in the Y for the first straight cut to Y363, once it reaches that Y point then it starts to go in B- moves so looking from the front the B axis is going clockwise which should be correct.

I will look into the X moves tomorrow, it may be that the HAAS system requires an X position as well or it may be a setup issue !!

That`s all I have for you for now, it is the small hours here so off to rest for me 🙂 🙂

Regards

Rob

[Anonymous]

Rob,

The toolpath appears to be correct. I may just have to mod the post on my end for my machine.

So here's another one for you on that same part. I've been trying to mill that wrapped slot. I've tried a couple way and keep getting either an error or a funky toolpath...any suggestions?

Thanks again!

[engineguy]

@Anonymous 

That would probably be best done with the "Rotary"  under the Multiaxis tab, I don`t think a straight forward 4th axis toolpath can be created to go full circle, as I don`t have the "Rotary" available to me I can`t try it out for you, needs someone with the full Rotary to do that one.

I will have a look and see if it can be done but it will have to be later as I have a lot to do right now, sorry.

Regards

Rob

[Anonymous]

I've been playing with your file a bit, setup is for A axis so I can verify posting. If you reset axis in setup to have rotary on Y axis, just change axis orientation in setup and regenerate tool paths.

May have to reset tool orientation in operations.

[engineguy]

@Anonymous 

Vic

Hmmm, interesting, never thought of splitting it up like that, seemed to work fine as a single 2D contour for me, have a look at the file attached and see if I have maybe missed something, seems to be OK to me ??

Regards

Rob

[Anonymous]

Good one Rob, for some reason I thought I only need to wrap radial slot and didn't even try to see if it would work in one shot.

[Anonymous]

On the other hand, I took closer look and it seems that doing it in one attempt violates model in two places and leaves uncut sections of strait slot.

Compare edges of model with tool path and it looks like splitting sections correctly aligns tool with each wall.

Single contour, OD used as wrap face, tool path not in sink with model edges.

Split sections, ID used as wrap face, tool path matches model edges.

[Anonymous]

Just to clarify, in wrap tool path tool points to center of model and therefore cannot machine walls of strait slots that don't align with center of model.

Separation of strait and radial slots enables use of tool orientation in machining of strait slots.

Wrap tool path disables tool orientation and if used for entire contour it violates all 4 walls of strait slots while leaving uncut sections on ID edges of walls. 

[Anonymous]

Rob, Vic

Thanks for participating. This is a really neat progression. I ran the wrap contour on the slot/hook with a 1/8" FEM and noticed that the toolpath angle was slightly off too just a very small mount. I also thought about trying a tool with the diameter equal to the slot width. I figured this would keep the tool centered, knock out the side walls, radius cuts and have only a couple toolpath movements. The toolpath looked good when I tried it; however, on the last area of the hook I saw it didn't complete the radius...I measured it and it's smaller then the tool rad. I'm going to look at the part again and report back.

Justin  

[Anonymous]

I used 3/32 end mill for small section because 1/8 end mill cannot reach whole slot and leave even stock for finish contour.

I programmed this part from perspective of holding tolerance and accuracy that may be required on print but I have no info as to what that is.

If slots do not have to fit tight dimensions of mating part and don't have any critical function, you could run it as Rob suggested but otherwise result will be inaccurate due to nature of how it works.

Walls of strait slots are parallel and do not line up with center point of model, therefore tool orientation is required that does not coincide with how radial slot is done as I explained before.

You can use wear compensation to adjust size of two strait slots, as for radial slot connection, you would have to adjust X value in program on finish pass to blend it with corners of strait slots.