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# Thread: G12.1 Polar Coordinate Interpolation

1. ## G12.1 Polar Coordinate Interpolation

Gentlemen,
Just wondering if a person can do more than just a square shape with a G12.1? Thank You

2. Yes.

3. Does anybody have examples of more complex shapes being done with G12.1?

4. Originally Posted by ggborgen
Does anybody have examples of more complex shapes being done with G12.1?
G12.1 is not "magic".
It interprets a linear and rotary axis as if it were 2 linear axiis.
So, on your lathe, it take your X(linear) axis and C(roatary) axis and treats them (on the programming side at least) as if they were X and Y on a mill.
That is, they are both radial (X is no longer Ø, and C is no longer °) and can be programmed in any way the you would on a mill... G1 point-to-point, G2, G3, Helical Interpolation so on and so forth.

So, if you can use trig to calculate the six X,Y points of a hex, then you could use G12.1 to program it.
This would apply to any shape that you could construct.
If the endmill is capable of walking around the shape, than it can be programmed in G12.1.

HTH

5. Originally Posted by ProProcess
G12.1 is not "magic".
It interprets a linear and rotary axis as if it were 2 linear axiis.
So, on your lathe, it take your X(linear) axis and C(roatary) axis and treats them (on the programming side at least) as if they were X and Y on a mill.
That is, they are both radial (X is no longer Ø, and C is no longer °) and can be programmed in any way the you would on a mill... G1 point-to-point, G2, G3, Helical Interpolation so on and so forth.

So, if you can use trig to calculate the six X,Y points of a hex, then you could use G12.1 to program it.
This would apply to any shape that you could construct.
If the endmill is capable of walking around the shape, than it can be programmed in G12.1.

HTH
If you have a Doosan lathe X is still a diameter in G12.1 mode.

6. Yes... as mentioned any shape can be programmed using G12.1. Not just on lathes but some mills and certainly for Multi-task machines (mill/turn centers or turn/mill centers).

Stevo's thread "G3 on rotary axis??" has some discussions with G12.1 programming which I and a coupe others posted some code for the shape he's dealing with.

Anyhow, here's some code for a fixture plate I just made a couple weeks ago in G12.1... and this shape is nowhere near being round....

G12.1
G1X18.85C3.72F1653.
Z-3.F200.
G41D#3020C2.72F380.
C-9.12
G2X18.25C-9.72I-.6J0.
G1X17.35
G3X16.6C-10.47I0.J-.75
G1C-12.33
G2X16.C-12.93I-.6J0.
G1X14.5289
G3X13.8925C-13.1936I0.J-.9
G1X9.9936C-17.0925
G3X9.73C-17.7289I.6364J-.6364
G1C-19.2
G2X9.13C-19.8I-.6J0.
G1X-9.13
G2X-9.73C-19.2I0.J.6
G1C-17.7289
G3X-9.9936C-17.0925I-.9J0.
G1X-13.8925C-13.1936
G3X-14.5289C-12.93I-.6364J-.6364
G1X-16.
G2X-16.6C-12.33I0.J.6
G1C-10.47
G3X-17.35C-9.72I-.75J0.
G1X-18.25
G2X-18.85C-9.12I0.J.6
G1C2.72
G2X-18.25C3.32I.6J0.
G1X-17.35
G3X-16.6C4.07I0.J.75
G1C6.9831
G3X-16.6716C7.3347I-.9J0.
G1X-17.9747C10.4047
G2X-17.9787C10.8639I.5523J.2344
G1X-17.3785C12.3493
G2X-17.1103C12.6223I.4636J-.1873
G1X-.1954C19.8022
G2X.1954I.1954J-.4603
G1X17.1103C12.6223
G2X17.3785C12.3493I-.1954J-.4603
G1X17.9787C10.8639
G2X17.9747C10.4047I-.5563J-.2248
G1X16.6715C7.3347
G3X16.6C6.9831I.8285J-.3517
G1C4.07
G3X17.35C3.32I.75J0.
G1X18.25
G2X18.85C2.72I0.J-.6
G3X18.967C2.3986I.5J0.
G1G40X19.0313C2.322
Z2.F1653.
G13.1