Intermediate 5 axis Help

# Thread: Intermediate 5 axis Help

1. ## Intermediate 5 axis Help

I'm lucky enough to be in a position where I have a sweet new trunion style 5AX to play with. I have some experience in 3+2, and for the most part the lessons learned there have applied. I was quite expectantly met by a 'known unknown' last week when I decided to put a chamfer on a chamfer. I can do the math, (or rather make the machine do the math) to keep track of the position of such a feature, but I can't for the life of me find what angles I need to tilt to. When BOTH rotary axes are not parallel/perpendicular XYZ (non-orthogonal?), I am beyond my current abilities to do the maths needed to derive the angels I must input. I have not yet figured out how to get a cam system to tell me what I need either. I've tried online calculators that have not produced correct results. I've spent time learning about rotational matrices, but thats a system of math I'm not familiar with, and even my counterpart who can do calculus hasn't yet got that ironed out. How do you guys do the math to pop the hole in this simple model?

2. Hot Rolled
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Originally Posted by iMillJoe
I'm lucky enough to be in a position where I have a sweet new trunion style 5AX to play with. I have some experience in 3+2, and for the most part the lessons learned there have applied. I was quite expectantly met by a 'known unknown' last week when I decided to put a chamfer on a chamfer. I can do the math, (or rather make the machine do the math) to keep track of the position of such a feature, but I can't for the life of me find what angles I need to tilt to. When BOTH rotary axes are not parallel/perpendicular XYZ (non-orthogonal?), I am beyond my current abilities to do the maths needed to derive the angels I must input. I have not yet figured out how to get a cam system to tell me what I need either. I've tried online calculators that have not produced correct results. I've spent time learning about rotational matrices, but thats a system of math I'm not familiar with, and even my counterpart who can do calculus hasn't yet got that ironed out. How do you guys do the math to pop the hole in this simple model?

We don't do the math. Let the cam system handle that.

3. Originally Posted by thesidetalker
We don't do the math. Let the cam system handle that.

How? Using Mastercam, I can create a plane on that double chamfer and do some programing on it. Mastercam will give me the XYZ position of the origin of that plane but I can't figure out how to get it to tell me at what angles A and C should be. The machine can do the math for the rotation about 3D space, a few different ways, but I'm struggling on what exactly that rotation is, once I've got both tables tilted. I don't have a post for this machine yet either...

4. Hot Rolled
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Originally Posted by iMillJoe
I don't have a post for this machine yet either...
That is the problem. Fix that first. Then :

1. Create a plane on that surface
2. Set it as your WCS and Toolplane
3. Create the toolpaths
4. Post the code.

I suppose, if necessary, use the generic 5 axis post included with Mastercam and modify the code it produces.

T

5. Diamond
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Originally Posted by iMillJoe
.......How do you guys do the math to pop the hole in this simple model?

Google Images for "compound angle trigonometry". Peruse the results and see which one makes sense to you.

6. Aluminum
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You just have to trig out where the hole is. Those features must be dimensioned on the drawing.

7. What machine do you have? Abc? Send me the model and i can give you numbers.

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In that particular situation, it appears that you are 45 degrees from a face, so rotary axis (C?) is going to be 45 - assuming you have the face parallel with an axis. What is the angle of the face to the base of the model? (should be easy to get that in a cad system off the model) That will be the A (or B) angle. No different than machining it 3+2.