Need Help!- G02 but X Y Z movement

[PEU]

I need to machine (mill) a circular groove but it requires a 3D movement, something like a G02 but on a slanted vertical plane, its an helicoid.

Look at this photo:


On top is the unmachined part, bottom is what I need to do and in the middle thats the part that rides on the machined part, its for a steering mechanism, I was not given further details.

The simple solution would be to put the 4th axis at the same angle needed for the cut and then selecting the plane and make a simple G02 movement, but I anticipate that setting the 4th axis at this angle would be a royal pita.

Is there a gcode for this movement or I need to interpolate little segments till I get the desired 3D curve?


Thanks!

[beege]

Simple to do with helical if your machine has it.

G02G19X_Y_Z_R_

What machine/control do you have?

Setting up your indexer at the desired angle shouldn't be that much of a pain. Probably the easiest solution.

[PEU]

Machine is Mach3 controlled, and I agree with you, maybe I complicated things in my mind when I posted, 4th axis at an angle would be the easiest solution. Thanks!

[PEU]

Now Im receiving an error in Mach3 (3.042 release) radius to end of arc differs from radius to startline at the first g03 line

here is the code:

g90
g0 z1
m3 s1000
g0 y1
m98 p100 L85 (call the sub 85 times for a full turn)
m5
m30

o100
g19 (select YZ plane)
g01 z0 f100
g03 y2.56 z-1.56 j0 k1.56 (I wanted to split the movement here to 2 quarter arcs)
g03 y4.12 z0 j-1.56 k0
g01 y1 z1
g17 (select XY plane just in case)
g91 (switch to relative)
g00 a4.23 (move the 4th axis)
g90 (switch to absolute)
m99

and here are the locations of the code:


What Im doing wrong?

Thanks!

[beege]

Originally Posted by PEU Now Im receiving an error in Mach3 (3.042 release) radius to end of arc differs from radius to startline at the first g03 line here is the code: g90 g0 z1 m3 s1000 g0 y1 m98 p100 L85 (call the sub 85 times for a full turn) m5 m30 o100 g19 (select YZ plane) g01 z0 f100 g03 y2.56 z-1.56 j0 k1.56 (I wanted to split the movement here to 2 quarter arcs) J relates to Y, K to Z, so J should be 1.56, K zero, g03 y4.12 z0 j-1.56 k0 Same here, J0, K1.56 g01 y1 z1 g17 (select XY plane just in case) g91 (switch to relative) g00 a4.23 (move the 4th axis) g90 (switch to absolute) m99 and here are the locations of the code: What Im doing wrong? Thanks!

Notes in red above...

[PEU]

Thanks!! from a CAM guy who is trying to handcode some stuff